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Dentin as a bonding substrate RICARDO M. CARVALHO, LEO TJÄDERHANE, ADRIANA P. MANSO, MARCELA R. CARRILHO & CARLOS AUGUSTO R. CARVALHO Dentin comprises the largest dental structure available for bonding. Because of its inherent morphological and physiological characteristics, reliable and durable resin–dentin bonding remains a challenging accomplishment that is subjected to multi-factorial interferences. Adhesive technology has evolved significantly over the past decade, resulting in improved predictability of resin–dentin bonds. This article reviews the present knowledge regarding resin–dentin bonding from the perspective of the dentin substrate. Since another article in the previous issue of Endodontic Topics already covers dentin structure and composition, the intention is not to fully review these aspects. Instead, basic principles of current bonding strategies used by adhesive agents are presented. Specific attention is given to describing how the morphology and physiology of dentin affect existing bonding mechanisms, how some chemical treatments of dentin can affect its properties and bonding, and finally how bonding to root canal dentin is currently viewed and understood. Received 27 October 2011; accepted 2 February 2012. Introduction Dentin comprises most of the tooth tissue. It has a tubular structure that is intimately connected to the pulp, and the harder enamel externally protects both. With few exceptions, most of the adhesive procedures in dentistry involve bonding to dentin. Dentin is a dynamic substrate (1) and its morphology and physi- ology directly affect the ability of adhesive systems to produce durable bonds to its prepared surfaces. This article reviews the present knowledge of dentin as a bonding substrate, mostly focusing on how dentin reacts to existing bonding strategies, how physiologically and pathologically induced structural and morphological changes affect bonding, and how surface pre-treatments modify the receptiveness of dentin to adhesives. Lastly, some current aspects of bonding to root dentin are also reviewed and dis- cussed. There was no intention to fully review all aspects of bonding to dentin. There are several reviews available on the topic that we highly recommend for those who are interested in more detailed information about adhesives and bonding strategies (2–8). Also, this double issue of Endodontic Topics presents a unique selection of review articles that, together, rep- resent what is currently known about dentin. Dentin composition and morphology Dentin has an intimate relationship with pulpal tissue in terms of embryological development and function: they form the dentinal–pulp complex and are not dissociable with respect to dental therapy. Human dentin is composed of approximately 70 w% of inor- ganic material, 18 w% of organic material, and 12 w% of water. When volumes are considered, organic material and water occupy the majority of the tissue (Table 1). These percentage ratios vary widely with the location and condition of the dentin. For instance, when dentin is demineralized, the water concentration increases significantly from 20% to about 50–70% by volume (9), which is a significant change in composi- tion that has profound implications in the mechanical properties of dentin and in the entire adhesive process. Morphology and permeability Dentin has a tubular structure and each tubule has an inverted-cone shape, with the larger diameter facing the pulp. As the inner dentinal surface area facing the pulp is smaller than the external surface area facing the dentin–enamel junction (DEJ), tubules are arranged Endodontic Topics 2012, 21, 62–88 All rights reserved 2012 © John Wiley & Sons A/S ENDODONTIC TOPICS 2012 1601-1538 62

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ODONTOLOGIA

Transcript of Dentina Como Sustrato

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Dentin as a bonding substrateRICARDO M. CARVALHO, LEO TJÄDERHANE, ADRIANA P. MANSO,MARCELA R. CARRILHO & CARLOS AUGUSTO R. CARVALHO

Dentin comprises the largest dental structure available for bonding. Because of its inherent morphological andphysiological characteristics, reliable and durable resin–dentin bonding remains a challenging accomplishmentthat is subjected to multi-factorial interferences. Adhesive technology has evolved significantly over the pastdecade, resulting in improved predictability of resin–dentin bonds. This article reviews the present knowledgeregarding resin–dentin bonding from the perspective of the dentin substrate. Since another article in the previousissue of Endodontic Topics already covers dentin structure and composition, the intention is not to fully reviewthese aspects. Instead, basic principles of current bonding strategies used by adhesive agents are presented. Specificattention is given to describing how the morphology and physiology of dentin affect existing bondingmechanisms, how some chemical treatments of dentin can affect its properties and bonding, and finally howbonding to root canal dentin is currently viewed and understood.

Received 27 October 2011; accepted 2 February 2012.

IntroductionDentin comprises most of the tooth tissue. It has atubular structure that is intimately connected to thepulp, and the harder enamel externally protects both.With few exceptions, most of the adhesive proceduresin dentistry involve bonding to dentin. Dentin is adynamic substrate (1) and its morphology and physi-ology directly affect the ability of adhesive systemsto produce durable bonds to its prepared surfaces.This article reviews the present knowledge of dentinas a bonding substrate, mostly focusing on howdentin reacts to existing bonding strategies, howphysiologically and pathologically induced structuraland morphological changes affect bonding, and howsurface pre-treatments modify the receptiveness ofdentin to adhesives. Lastly, some current aspects ofbonding to root dentin are also reviewed and dis-cussed. There was no intention to fully review allaspects of bonding to dentin. There are several reviewsavailable on the topic that we highly recommend forthose who are interested in more detailed informationabout adhesives and bonding strategies (2–8). Also,this double issue of Endodontic Topics presents aunique selection of review articles that, together, rep-resent what is currently known about dentin.

Dentin composition andmorphologyDentin has an intimate relationship with pulpal tissuein terms of embryological development and function:they form the dentinal–pulp complex and are notdissociable with respect to dental therapy. Humandentin is composed of approximately 70 w% of inor-ganic material, 18 w% of organic material, and 12 w%of water. When volumes are considered, organicmaterial and water occupy the majority of the tissue(Table 1). These percentage ratios vary widely with thelocation and condition of the dentin. For instance,when dentin is demineralized, the water concentrationincreases significantly from 20% to about 50–70% byvolume (9), which is a significant change in composi-tion that has profound implications in the mechanicalproperties of dentin and in the entire adhesive process.

Morphology and permeability

Dentin has a tubular structure and each tubule has aninverted-cone shape, with the larger diameter facingthe pulp. As the inner dentinal surface area facing thepulp is smaller than the external surface area facing thedentin–enamel junction (DEJ), tubules are arranged

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Endodontic Topics 2012, 21, 62–88All rights reserved

2012 © John Wiley & Sons A/S

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in a radial disposition, which determines the significantregional variations in tubule concentration by surfacearea. Near the pulp, the area occupied by dentinaltubules reaches 22% while near the DEJ it representsonly 1% of the dentin surface (10,11). Each tubule isinternally surrounded by peritubular dentin, a cuffrich in mineral content and having a variable widthaccording to its location along the tubule. Conversely,intertubular dentin is rich in organic material (mostlycollagen fibrils) and plays a fundamental role in adhe-sive procedures. Considering that dentin permea-bility occurs primarily via dentinal tubules, regionalvariations in the caliber and density of tubules causesignificant and proportional changes in dentin perme-ability (12). Additionally, when dentin is acid-etched,compositional characteristics are modified and a sig-nificant increase in permeability occurs. Variations inthe morphology and permeability of dentin directly

affect bonding (2,13). As will be further discussed inthis article, such variations are important factors to beconsidered during adhesive procedures with dentin.Table 2 illustrates superficial changes that occur as afunction of location and acid treatment in dentin. Therelationship between morphology and permeabilityand how that affects adhesion have been thoroughlydiscussed elsewhere (12).

Mechanical properties

Although several research groups have investigated themechanical properties of dentin in the past, the topic hasrecently gained more importance as a method of analyz-ing and better understanding the adhesive mechanismsof this substrate (14–16). Dentinal microstructure andmechanical properties are determinants for most proce-dures in restorative dentistry (15,16). Regional differ-ences in the relative composition of dentin result insignificant differences in mechanical properties between,for example, superficial and deep dentin, coronal andradicular dentin, and also according to the orienta-tion and distribution of dentinal tubules (16–26).Physiological and pathological processes such as aging,sclerosis, and dental caries can also induce significantalterations in the mechanical properties of dentin (27–31) (Table 3). Chemicals usually employed in dental

Table 1: Basic composition of mineralized dentin

Inorganic Organic Water

% by weight 70 18 12

% by volume 30–50 30–50 20

Carvalho et al., 1996 (9); Marshall et al., 1997 (16).

Table 2: Changes in the area occupied by tubules, peritubular dentin, and intertubular dentin before (B) and after(A) acid-etch, as a function of location

Distance frompulp (mm)

Number oftubules / cm2

Radius oftubules (mm)

Percentage of surface area

Tubules Peritubular Intertubular

B A B A B A* B A

Pulp 4.5 ¥ 106 1.25 1.5 22.1 33.8 66.3 – 11.6 66.2

0.1–0.5 4.3 ¥ 106 0.95 1.5 12.2 30.4 36.6 – 51.2 69.6

0.6–1.0 3.8 ¥ 106 0.80 1.5 7.6 26.9 22.9 – 69.4 73.1

1.1–1.5 3.5 ¥ 106 0.60 1.5 4.0 24.7 11.9 – 84.2 75.3

1.6–2.0 3.0 ¥ 106 0.55 1.5 2.9 21.2 8.5 – 88.6 78.7

2.1–2.5 2.3 ¥ 106 0.45 1.5 1.5 16.2 4.4 – 94.2 83.9

2.6–3.0 2.0 ¥ 106 0.40 1.5 1.0 14.1 3.0 – 96.0 85.9

3.1–3.5 1.9 ¥ 106 0.40 1.5 1.0 13.4 2.9 – 96.2 86.6

Adapted from Nakabayashi & Pashley, 1998 (11).* Assumes the more mineralized peritubular dentin is completely dissolved by the etchant.

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therapy such as whitening products, cleansing agents,etc. also affect the properties of dentin. The implica-tions of these alterations on the ability of adhesives tobond to dentin will be discussed later on in this review.

Principles of adhesion to dentinBonding to dentin can currently be regarded as a formof tissue engineering (8). It is essentially accomplishedby an exchange mechanism that replaces mineral withresin monomers to form a new biocomposite madeout of collagen fibrils and cured resin (32,33). Unlikeclassical tissue engineering, this new biocomposite is notintended to be resorbed and replaced by normal dentin.Instead, it is expected to form a tight and permanentconnection between dentin and composite resins.

The first step in conventional etch-and-rinsebonding to dentin is the creation of pathways for resininfiltration. This is traditionally accomplished by treat-ing dentin with acidic solutions. This dissolves themineral content of the top 5–8 mm of dentin andleaves behind a porous network of highly cross-linkedtype I collagen suspended in water (34). The next stepis the infiltration of resin monomers. Ideally, resinmonomers should be able to displace water within andaround the collagen fibrils without reducing the size ofthe already small porosities created by acid etchingand completely replace that water with the infiltratingresin. When infiltration is complete, light activationis applied to cure the resin and result in a polymer–collagen biocomposite also known as the hybrid layeror resin-interdiffusion zone (32,33) (Fig. 1). Self-etchadhesive systems share the same ultimate objective

when bonding to dentin, but they combine the crea-tion of pathways and resin infiltration into a singlestep. Regardless of the bonding strategy, the abovebonding mechanism is rarely accomplished to perfec-tion (3,4,8). The morphological and physiologicalheterogeneity of dentin have been described as themajor obstacles to achieving uniform, reproducibleand reliable bonding (2,6). Although dentin hasalways been described and referred to as a whole, someregard that as an oversimplification because differenttypes of dentin, reflecting different functions andbearing their own specificities, have been identified(28,35). Biological, structural, and clinical factors suchas dentin depth, location, age, wetness, sclerosis,caries, pre-treatments, etc. have all been shown tosignificantly interfere with the resultant quality ofresin–dentin bonds (2,16) (Fig. 2). Some of these willbe explored further in this review.

Etch-and-rinse adhesivesEtch-and-rinse adhesives are characterized by utilizinga separate, initial etching step to create the pathwaysfor resin infiltration. Etching is followed by rinsing thesurface with water, which aims to completely removethe dissolved smear layer and minerals from the dentinsurface, leaving a scaffold of collagen fibrils exposed,the porosity of which is maintained because theinterfibrillar spaces are filled with the rinse water(9,33,34,36). The next step consists of replacing thewater occupying the intra- and interfibrillar collagenspaces with resin co-monomers. Traditional 3-stepetch-and-rinse adhesives utilize primers that contain

Table 3: Mechanical properties of dentin

Mechanical property Mineralized dentin Demineralized dentin Authors

Microtensile strength (MPa)* 60–100 10–25 Sano et al., 1994 (18)50–55 (caries affected) 14–16 (caries affected) Carvalho et al., 1996 (9)

Carvalho et al., 2001 (20)

Modulus of elasticity* 13–18 Gpa 50–70 MPa Sano et al., 1994 (18)Carvalho et al., 1996 (9)Maciel et al., 1996 (39)

Microhardness (Knoop) 60–70 40–50† Fuentes et al., 2003 (115)

Density (g/cm3) 2.01 1.05 Carvalho et al., 1996 (9)

* Data obtained by microtensile bond strength method.† Superficially acid-etched with phosphoric acid.

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hydrophilic monomers solvated in acetone, ethanol,or water. These primers displace water and prepare thecollagen scaffold for the subsequent infiltration ofthe solvent-free, hydrophobic bonding resin (6,8,12).Simplified, user-friendly 2-step versions combine thehydrophilic primer and the hydrophobic resin into asingle solution. This combination, however, resultsin several drawbacks for the simplified versions of thiscategory of adhesives. These drawbacks ultimatelyresult in lower bonding reliability when comparedto the 3-step versions. We refer the reader to moredetailed reviews on this topic (3,6–8). Although adhe-sive infiltration into the collagen scaffold appears tobe a straightforward mechanism, it is rather negativelyaffected by several factors that always result in theinability of resin–solvent mixtures to completelyremove water and fully infiltrate the demineralizedzone (3,6,8). In contrast to most bioengineered scaf-folds that present porosities in the range of 5–20 mm,natural dentin collagen scaffolds offer nanometer-sized

porosity (c. 10–30 nm) for resin infiltration (8,37).This collagen mesh has a very low modulus of elasticity(c. 6–10 MPa) (38–40). Rinsing water creates stronghydrogen bonding with collagen peptides and pre-vents interpeptide hydrogen bonding that would causethe mesh to collapse and eliminate the already-reducedporosity for resin infiltration (41,42) (Fig. 3). Exten-sively air-drying demineralized dentin to remove watershould, therefore, be avoided as the porosity willdisappear due to shrinkage of the fibril network (9).The expansion of the collagen mesh as a result of thepresence of rinsing water forms the basis of the successof the wet-bonding technique currently recommendedfor all etch-and-rinse adhesives (43). Even though theporosity can be maintained with the presence of waterin the wet-bonding technique, its replacement bysolvents and/or monomers with a lower capacityfor hydrogen bonding with collagen will cause slightshrinkage of the mesh during resin infiltration andresult in reduced interfibrillar spaces (41,44).

Fig. 1. Transmission electron microscope (TEM) image of the dentin–composite interface created with a simplified2-step etch-and-rinse adhesive. The mineralized dentin supports the collagen network exposed with acid etching andsubsequently infiltrated with the adhesive, forming the hybrid layer (HL). The more hydrophobic layer of adhesive(AL) is located between the hybrid layer and composite. Image courtesy of Dr. Pekka Mehtälä.

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Etch-and-rinse adhesives are known for beingtechnique-sensitive (6,8), and this is mostly due tothe difficulties in determining the adequate surfacemoisture for each adhesive being applied. It has beendemonstrated that acetone-based adhesives require awetter surface than ethanol-based adhesives (45,46).Water-based and ethanol-based primers have showna self-rewetting ability when applied to a rather drysurface (47). This is also a result of the higher solubil-ity parameter of ethanol when compared to acetone(41,42). Water is considered to play an antagonisticrole in the hybrid layer formation with etch-and-rinseadhesives (12,34). While some moisture is necessaryto maintain collagen fibril expansion, thus preservingthe pathways for resin infiltration, excess moisture maycause a phase separation between hydrophobic andhydrophilic monomers, resulting in the formation ofblisters and voids at the interface with the consequentnegative effects on the uniformity of the resin infiltra-tion (12,48,49). Additionally, the inability to removeresidual solvents and water from the adhesive (50)results in reduced conversion of resin monomers withnegative consequences to the mechanical propertiesof the interface (51–53). The ultimate consequence ofpoor resin infiltration into the demineralized zone is

a reduced durability of the bonded interface. This ismainly caused by the uneven stress distribution alongthe components of the hybridized zone (3,54,55), thepossibility of enzymatic degradation of collagen fibrilsthat were left exposed (8,56), and the hydrolysis of thepoorly formed adhesive polymer (3,8,57).

To avoid problems related to the presence of waterin the traditional wet-bonding technique, the ethanolwet-bonding concept has been proposed (58). In theethanol wet-bonding technique, demineralized dentinis saturated with ethanol to replace the rinsing waterbefore adhesive application. The apparent successof the method relies on the fact that ethanol has arelatively higher solubility parameter, maintains theinterfibrillar spaces for resin infiltration, and elimi-nates water that causes a phase separation betweenhydrophilic and hydrophobic monomers. Under theethanol wet-bonding approach, hydrophobic resinscan be used to infiltrate the collagen mesh insteadof less stable hydrophilic monomers. The use of theethanol wet-bonding technique has been shown toimprove resin infiltration, increase bond strength, andreduce nanoleakage and micropermeability withinthe hybrid layer [Carrilho et al. (2011 unpublisheddata); Manso et al. (2011 unpublished data)] (59,60),

Fig. 2. The common phenomena in dentin, all of which will affect the dentin as the substrate for bonding. NCCL:non-carious cervical lesion.

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resulting in improved bond durability (8,60). Thisimproved bond durability when using the ethanolwet-bonding approach can be explained via theimproved collagen encapsulation by resins (59) andsome inhibitory effect of dentin proteases (i.e. matrixmetalloproteinases, MMPs) known to cause collagendegradation in resin–dentin bonds (61). While demin-eralized dentin treated with the ethanol wet-bondingtechnique seems to be a promising substrate for resininfiltration, there are concerns regarding the effectsof ethanol-saturated dentin on the polymerizationof the adhesives (62). At the moment, no commercialadhesive is available that has been developed to be usedaccording to the ethanol wet-bonding technique.

The three-step version of etch-and-rinse adhesives isregarded as the most reliable system currently available(5,6,8). One advantage of a three-step bonding pro-cedure is the opportunity to use each step to introducetherapeutic benefits (8). Examples of these are the

possibility of incorporating MMP inhibitors in theetching and/or priming steps (63–65) and smallmolecules such as fluoride in the hydrophobic resin(8,66,67). Despite all of the advantages and scientificevidence of the superior performance of three-stepetch-and-rinse adhesives, the multi-step clinical proce-dure is not appealing to clinicians and results in noinnovation from the manufacturers.

Self-etch adhesivesSelf-etch adhesives are characterized by the absenceof a separate acid-etching step. Instead, the creation ofresin diffusion pathways is achieved by the presence ofacidic monomers in the composition that simultane-ously etch and prime the dental substrate (4,6). Self-etch adhesives are also subdivided into 2-step and1-step categories (68). Clinical and laboratory per-formances of these adhesives seem to be material

Fig. 3. The effect of moisture on demineralized dentin matrix collagen. (a) Schematic description of dry dentin matrixcollagen peptides that are stiff because of interpeptide hydrogen (H) bonds. Due to the H-bond, the interpeptidedistance (<10 nm) is too small to allow monomer penetration between the collagen fibrils. (b) The collagen matrixis collapsed and penetration of the adhesive does not occur. Arrow: the direction and width of the matrix shrinkage.(c) In water-saturated dentin matrices, water (H2O) molecules cluster around the functional groups in collagenpeptides that can form the H-bond. Due to the water’s high Hoy’s solubility parameter, the interpeptide H-bondscannot form, and the interpeptide distance is wider. (d) The water-saturated matrix is expanded and soft, and allowsfor the penetration of adhesive molecules between the collagen fibrils.

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dependent, but the 2-step systems are systematicallyreported as being more favorable (69,70).

The acidic characteristics of the active monomers inself-etch adhesives are responsible for dissolving thesmear layer and demineralizing the underlying dentin(71). This demineralization is self-limiting because theacidity of the monomers is gradually buffered by themineral content of the dentin (72). This implies thatthe resultant morphological aspect of the bondedinterface is largely dependent on the characteristics ofthe dentin to which the adhesive is being applied andon the aggressiveness of the acidic monomers (73–75). Accordingly, self-etch adhesives have been classi-fied as strong (pH < 1.0), intermediate (pH = 1.5),and mild (pH > 2) (68). More recently, two otheradhesives became available that present lower acidity(pH > 2.5) and were classified as ultra-mild self-etchadhesives (Clearfil S3 Bond, Kuraray Inc., Japan andAdper Easy Bond, 3M ESPE, USA). As expected,the demineralization depth is directly related to theaggressiveness (73,74). Strong self-etch systemsproduce interfaces that resemble those of etch-and-rinse systems while ultra-mild versions barely dissolvethe top dentin surface and leave tubules occluded withsmear plugs. The partial demineralization resultingfrom mild and ultra-mild self-etch systems has beenreported to be an advantage because of the possibilityof chemical interaction between some functionalmonomers (such as MDP and 4-META) and theremaining hydroxyapatite crystals along the collagenfibrils (76). It has been claimed that this chemicalbonding results in the improved bond durabilityreported for these systems (6,77,78), but the experi-mental data is conflicting (79–81).

The success of self-etch adhesives is largely relatedto their simplicity of use and to the theoretical abilityto etch and infiltrate simultaneously, thus preventingdiscrepancies between demineralization and infiltra-tion (4,6,77,78). This concept, however, has beenrecently challenged (82) as zones of partially deminer-alized but not infiltrated dentin have been observedbeneath the hybrid layer. This was more evident forthe simplified versions of self-etch adhesives (1-stepand all-in-one systems), but also occurred with themore traditional 2-step materials. Simplified, 1-stepversions of self-etch adhesives have been regarded asthe least reliable adhesives available. They have con-sistently resulted in inferior performance in both labo-ratory and clinical testing (6,69,70). These versions

are highly hydrophilic and this makes them susceptibleto water sorption and hydrolysis, thus seriously com-promising the stability of the bonded interface overtime (3,6,83,84).

Currently, one 2-step system (Clearfil SE Bond,Kuraray Inc., Japan) is regarded as the gold standardof self-etch systems (4). The success of this materialhas been attributed to its functional monomer (MDP),which is capable of chemically bonding to hydroxy-apatite, and to the stability of its filled, solvent-freebonding resin (4,6).

Glass ionomers and glassionomer adhesivesGlass ionomers are currently regarded as the onlymaterials that self-adhere to mineralized dental tissues(76). Bonding to dentin is generally accomplishedby a two-fold mechanism. A short polyalkenoic acidtreatment removes the smear layer and exposes colla-gen fibrils up to about 0.5–1.0 micron (85), and glassionomer components can diffuse in to establish amicromechanical interaction following the principlesof hybridization (69,86,87). Additionally, a chemicalbond is attained by the ionic interaction between thecarboxyl groups of the acid and the calcium ions ofthe hydroxyapatite that remained attached to thecollagen fibrils (76). To what extent each of thebonding mechanisms contributes to the actual inter-facial strength is unclear. It appears that the use of thepolyalkenoic acid pre-treatment is crucial for optimiz-ing bond strength because it removes the smear layer,thus promoting a more intimate contact of the glassionomer with the underlying dentin (88). Also, theremoval of the smear layer increases dentin permeabil-ity and provides an additional water source to benefitthe acid–base setting reaction of the glass ionomer(89). When the smear layer is not present, i.e. in thecase of fractured dentin, it seems that the use of anacidic pre-treatment is not necessary (88).

The adhesion of glass ionomers to dentin has beenproven to be highly successful clinically in Class Vnon-carious cervical lesions (70,90). The chemicalbond to the remaining apatite and the maturationof the glass ionomer at the interface caused by themoisture from the dentin surface both seem to beimportant mechanisms by which the bonding of glassionomers to dentin becomes more resistant to degra-dation over time (69,88).

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Structural characteristics thataffect bonding

Smear layer

Whenever dentin is operated on by cutting or abradinginstruments, the resulting surface will be covered by a0.5–2 micron smear layer and dentinal tubules will befilled with several microns of smear plugs. It has beengenerally accepted that smear layers and plugs arecomposed of hydroxyapatite particles and disrupted,denatured collagen fibrils that change according to thecharacteristics of the region from where they wereformed (91–96). The presence of the smear layer andsmear plugs drastically reduces dentin permeability(12). While this can be seen as beneficial for biologicalprotection of the pulp, it is regarded as an obstacle thatdirectly affects how adhesives interact with dentin.

Etch-and-rinse adhesives are reported to be lessaffected by the presence of the smear layer and smearplugs because the strong phosphoric acid dissolves,and further water rinsing removes, the residues fromthe surface. This, however, results in increased perme-ability and increased moisture on the surface that caninterfere with adhesion (2). Additionally, the ability ofphosphoric acid to remove collagen remnants from thesurface has been questioned. Raman microspectro-scopic studies revealed that collagen within the smearlayer is denatured by acid-etching and not removedupon rinsing (94,95). The gelatinized collagen left onthe surface may interfere with further resin infiltrationand represent another confounding factor in bondingto dentin (3).

Self-etch adhesives incorporate the smear layer andsmear plugs into the bonded interface. Hence, thetype of smear layer produced on the dentin surfacelargely influences the bonding effectiveness (97,98).Smear layers of different thickness, density, andcomposition are formed depending on the cuttinginstrument used (97,99). Because smear layers canphysically block the diffusion, and chemically bufferthe acidity of the resin monomers (98,100–102),the bonding effectiveness of self-etch adhesivesdepends on their ability to deal with the smear layer(73,99,103). In that regard, there is evidence thatthick smear layers can impair the bonding of (ultra-)mild self-etch adhesives (73,97,98,103). It is thusrecommended that cavity walls be finished with extra-fine diamond burs (97,104), and that mild self-etch

adhesives be applied with continuous agitation toimprove monomer infiltration and uniform hybridlayer formation (105–107).

Aging

Dentin structure, chemistry, and properties changeover time (108–111). Physiological sclerosis (with thereduction in tubule diameter) and the presence ofmineral deposits (with the consequent reduction indentin permeability) are among several events thatoccur with aging which are potential deterrents ofdentin bonding effectiveness (2). However, fewstudies have investigated the effects of tooth age ondentin bond strength (112–114). While some differ-ences in the mode of failure and material dependencehave been reported in these studies, in general therewere no significant differences in bond strengthsbetween young and old teeth.

Depth, location, and tubule orientation

Because of the regional variance of dentin mor-phology relative to tubule density and lumina, thewater content of dentin also varies accordingly, as wellas its properties (115) and permeability when thesmear layer and smear plugs are removed. The intrinsicwater content of dentin is greater near the pulp anddiminishes significantly toward the dentin–enameljunction (DEJ). This difference in surface moisturehas been considered to be a factor that affectsdentin bonding and results in lower bond strengthsin deep compared to superficial dentin (12,116,117).However, as adhesive systems became more hydro-philic, lower bond strengths obtained in deeper dentinhave been more associated with the reduced availabil-ity of intertubular dentin for the hybrid layer forma-tion than with surface wetness when the bond is closerto the pulp (13,118,119). In general, bond strengthsin deep dentin are reported to be 30–50% lower thanin superficial dentin (118,120). By using the micro-tensile bond strength testing method (121), research-ers were able to demonstrate regional variances inbond strength to root dentin (122) and to the differ-ent walls of an MOD cavity preparation (123). Ingeneral, bond strengths tend to be lower in the apicalthird of the root and at the cervical margins of a cavity.

The orientation of the dentinal tubules has been re-ported to have a significant effect on the morphology of

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the hybrid layer produced by etch-and-rinse adhesives.Hybrid layers were thicker and resin tags were longerwhen bonding to dentin with a perpendicular tubuleorientation. Conversely, thinner hybrid layers and anabsence of resin tags were reported for dentin with aparallel tubule orientation (124). The effect of tubuleorientation on bond strength, however, remains incon-clusive as it appears to vary according to the adhesiveused and testing method, as well as being subjected toconfounding variables such as dentin depth and location(125,126).

Bonding to altered dentin

Caries-affected and caries-infected dentin

While most of the current knowledge about dentinbonding has been generated from laboratory studies(5), it is self-evident that adhesives should prove theireffectiveness when bonded to clinically relevant dentinsubstrates. In that regard, fewer studies are availablethat have profoundly investigated the bonding charac-teristics to clinically altered dentin, and most impor-tantly, devised approaches to improve the quality ofbonding to such substrates (2,7). The minimallyinvasive dentistry concept (127) determines that cavitypreparation should be limited to caries removal.Regardless of the debatable question as to the extentto which carious dentin should be removed, mostof the caries excavation methods are known to leavecaries-infected and/or caries-affected dentin as thebonding substrate for adhesives (128). Additionally,resultant bond strengths may also be influenced by thecaries removal method and the type of adhesive used(128,129).

The bond strengths to caries-affected dentin havebeen systematically reported to be 20–50% lowerthan to sound dentin (2,30,128,130–132). Bondstrengths tend to be even lower when bonding tocaries-infected dentin (133,134). Caries-affected andcaries-infected dentin are more porous (31,135),contain significantly more water (136), and the hybridlayers tend to be much thicker, but not necessarilywell-infiltrated in caries-altered dentin, irrespective ofthe bonding strategy (131,137,138).

The lower bond strength to caries-affected dentin isa consequence of the structural changes caused by theprogression of the caries lesion. Caries progressionreduces the mineral content and crystallinity of the

hydroxyapatite, and causes alterations in the secondarystructure of collagen (139). As well, reduced distribu-tion of sound collagen fibrils and proteoglycans werefound in caries-affected dentin (140). All of this resultsin a substrate with reduced mechanical properties(16,136,141,142), which directly affects the result-ant bond strength. Infiltration of adhesive resins isalso hampered by the presence of mineral casts (i.e.whitlockites) along the tubules (52,132,143,144).There is also evidence that adhesives are poorly polym-erized at the bonded interfaces of caries-affecteddentin (52,144).

Reported variations in the bond strength to caries-altered dentin are likely a result of the differences inthe aggressiveness of the methods used to removecarious tissue in each specific study (128). In eachstudy, etch-and-rinse adhesives tend to produce higherimmediate bond strength to caries-affected dentinthan self-etch ones (130,145,146). However, suchdifferences seem to disappear after short-term waterstorage (145). In that regard, long-term bondstrength studies to caries-affected dentin are stilllacking, despite the obvious higher relevance of suchstudies when compared to sound dentin. Becausedentin reactions initiate readily after caries lesionsaffect enamel, it is expected that therapeutic adhesiverestorations will always be bonded to different degreesof altered dentin in a clinical setting. In that scenario,reported bond strengths to sound dentin are not pre-dictive of the adhesive performance when bondedto altered dentin. Considering the long-term clinicalsuccess of posterior composite restorations in retro-spective studies (147–149), it is possible that thereported lower bond quality produced by adhesives tocaries-altered dentin is not as clinically relevant as onewould think. How much bond strength is necessary todetermine clinical success remains to be determined,perhaps by testing the interfacial strength of adhesivejoints of retrieved teeth that had been in clinical func-tion for several years (7).

Sclerotic non-carious cervical lesions

Non-carious cervical lesions (NCCL) present a uniquestructure that has no similarities with any other type ofdentin. It is characterized by a structure composedof a top hypermineralized layer of varied thicknesswith several bacterial inclusions that is sitting on abed of denatured collagen fibrils (Fig. 4). This top

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layer transitions to a dentin underneath that presentsirregular tubular occlusion by mineral casts, typicalof sclerotic dentin (150). Similarly to caries-affecteddentin, bond strengths to NCCL have been reportedto be 20–40% lower than to sound dentin, irrespectiveof the bonding strategy (150–152). This has beenattributed to the presence of the microbial matrix andentrapment of bacteria during the hybrid layer forma-tion, the inability of acids to completely dissolve the

hypermineralized layer, the presence of denatured col-lagen at the base of the hypermineralized layer, and thepresence of sclerotic casts that obliterate the tubules(71,150). All of these factors compromise the ability ofadhesives to create pathways for resin infiltration and,consequently, the ability to completely infiltrate theadhesive resin. The irregular edges of the hybrid layerand the presence of bacterial inclusion have also beenpointed out as stress-raising sites that cause prematurefailure when the interface is stressed (150). Methodsattempting to improve bond strength to NCCLhave rendered inconclusive findings. Roughening thesurface with burs to remove the hypermineralized layerprior to bonding has resulted in thicker hybrid layerswith different adhesives (153), but did not seem toincrease retention rates in clinical trials (90,154). Simi-larly, extending etching times from 20 s to 30 s havebeen shown to increase bond strength for some adhe-sives, but to reduce it for others (155).

Most of the knowledge concerning the structure ofNCCL and how it responds to bonding approacheswas generated during the late 1990s and early 2000s(74,122,150,151). Recent laboratory studies thatinvestigate the bonding mechanisms with currentadhesive systems are lacking. Clinical trials, however,are widely available because NCCL are the lesionsrecommended for testing the clinical effectiveness ofadhesive systems (156). Interestingly, the surprisinglyhigh clinical survival rates of NCCL restorationssuggest that the difficulties in producing reliable bondsto NCCL as reported by laboratory studies may not beas relevant as previously thought (2,5–7).

Dentin pre-treatments thatadversely affect bondingThis section reviews chemical treatments that havebeen reported to affect both the physical and bondingproperties of dentin, and that are more closely relatedto clinical procedures involving coronal and rootdentin.

Sodium hypochlorite

Sodium hypochlorite (NaOCl) is a well-known, non-specific proteolytic agent that is capable of removingorganic material, magnesium, and carbonate ions fromthe dentin surface (157). It remains the most widelyused chemical irrigant for endodontic therapy due to

Fig. 4. The dentinal surface in a non-carious cervicallesion (NCCL). (a) Light microscope image from thedeepest part of a NCCL. B: stained, unmineralized bac-teria; HM: hypermineralized surface layer covering thelesion; SD: intact sclerotic dentin. The pointers indicatethe remnants of mineralized bacteria. (b) CorrespondingTEM micrograph of the same area of the NCCL lesion.The hypermineralization of the surface layer (HM) isidentified by its electron density compared to the under-lying sclerotic dentin (SD). Reproduced with permissionfrom Tay et al., 2000 (71).

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its antibacterial and organic tissue-dissolution proper-ties (158–160). Despite the propagated benefits ofdisinfection and cleaning of root canals, NaOCl haspotential negative effects on the mineral content ofdentin structures (161) that may reduce its mechanicalproperties (22,158,162) and compromise the sealingability of endodontic fillings (163).

Although NaOCl is not a pre-treatment typicallyrecommended for adhesive procedures in general, it isnot uncommon that, during endodontic therapy, theirrigant “contaminates” the coronal portion of thetooth, which may later be restored with an adhesiverestoration. Also, clinicians may use NaOCl to irrigateroot canals prior to luting fiber-reinforced resin postsusing adhesive systems and resin cements. Severalstudies have demonstrated that NaOCl compromisesthe bond strength between adhesive agents and dentin(164–171). The compromising mechanism likelyoccurs because the reactive residual free-radicals gen-erated by the oxidizing effect of NaOCl compete withthe propagating vinyl free-radicals generated duringthe curing of the adhesive, thus leading to incompletepolymerization by premature chain termination (165).This compromising effect seems to occur similarly withboth etch-and-rinse and self-etch adhesives (165,169)whenever the adhesives are applied to dentin that hasbeen previously treated with NaOCl.

Antioxidants/reducing agents have been recom-mended to reverse the compromised bond strengthsto dentin pre-treated with NaOCl. A 10% solution ofsodium ascorbate is among the most investigatedagents used to revert the oxidizing effect of NaOClprior to bonding with adhesive resins (165,169,171,172). Antioxidants such as sodium ascorbate control/revert oxidation effects by mechanisms that involvefree radical chain-breaking, metal-chelating, and freeradical quenching (169). All of these can restore theredox potential of the oxidized dentin surface andimprove the polymerization of the adhesive resin. Theability of sodium ascorbate to revert the effects ofNaOCl seems to depend on the concentration andapplication time of the former (172). For instance,10% sodium ascorbate applied for 5 s was not capableof reverting the negative effects of a 6% NaOCl treat-ment for 30 s, but a 10 s treatment was (169). Otherantioxidants/reducing agents have been more recentlyinvestigated as potential candidates to revert the nega-tive effects of oxidants such as NaOCl on resin–dentinbonds. These include sodium thiosulfate solutions

(i.e. p-toluenesulfinic acid sodium salt; Accel, SunMedical Co. Ltd., Kyoto, Japan) (169,173) and ros-marinic acid (a-o-caffeoyl-3,4-dihydroxyphenyllacticacid) extract from rosemary (169). These agents seemto be more effective than sodium ascorbate as lowerconcentrations are used for shorter application times(169). While effective bonding to NaOCl-treateddentin can be accomplished with the prior use ofantioxidant/reducing agents, posterior resin infiltra-tion of NaOCl-treated dentin was not capable ofrestoring damaged surface properties (22). The clini-cal importance of this remains to be determined.

Hydrogen peroxide

Hydrogen peroxide or peroxide-releasing agents suchas carbamide peroxide and sodium perborate are well-known compositions largely used for external andinternal tooth bleaching (174). Bleaching is currentlyregarded as a safe and effective method of inexpen-sively treating discolored teeth (175).

The effects of hydrogen peroxide, the active bleach-ing species, on dentin and dentin bonding share a lotof similarities with sodium hypochlorite. Hydrogenperoxide is a potent oxidant and a number of studieshave reported microstructural changes in dental hardtissues induced by bleaching (176). Histologicalalterations to enamel, changes in the mechanical prop-erties of dentin (177), and alterations in the organiccomponent of dentin (178) have been reported. Thesewere more recently reviewed and considered, ingeneral, to be minor and not clinically relevant (179).

Conversely, studies are almost unanimous in demon-strating that hydrogen peroxide has negative effects onresin–dentin bonding. Reduced bond strengths haveconsistently been reported when adhesives are imme-diately applied to bleached dentin, regardless of thebonding strategy (165,180–184). The mechanismsinvolved are similar to those resulting from the useof NaOCl on dentin prior to bonding (see above).Hydrogen peroxide diffuses and remains entrapped indentin. The compromising effect is due to the residualoxygen present in the dentin pores that impairs infil-tration and inhibits polymerization of the adhesiveresin (184–186). The effects seem to be dependent onthe concentration of the bleaching agent, being worsewith higher concentrations (181). Because of this,there is a general recommendation that bonding pro-cedures to bleached teeth should be delayed for 24 h

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to 2 weeks after bleaching, when the negative effectsare no longer observed (183,187–191).

Alternatively, reversal of compromised bonding canbe obtained by treating hydrogen peroxide-treateddentin prior to bonding with sodium ascorbate (165,192), catalase, ethanol (193), or ascorbic acid (194,195). All of these are antioxidants/reducing agentsthat have been shown to be able to eliminate theadverse effects of hydrogen peroxide and restorebond strengths to values which are comparable tothose obtained on untreated dentin in a similar way asobserved for dentin treated with NaOCl. In general,antioxidants/reducing agents are applied for the sameduration as the bleaching treatment (165). One recentstudy showed that the amount of sodium ascorbaterequired for the reduction of hydrogen peroxide isdirectly related to the concentration of the latter. Inaddition, the reaction kinetics between oxidant andantioxidant showed that a longer application time ofsodium ascorbate did not influence the effectiveness ofthe reaction and that 5 min is sufficiently long for thisantioxidant to exert an antioxidant effect (196).

Dentin pre-treatments withpotential advantageous effectson bondingIn addition to the mostly unfavorable effects of chemi-cal treatments on dentin bonding, there are severalapproaches that aim to improve either the immediateor the long-term resin–dentin bond strength (197).Most of them aim to preserve the integrity of thehybrid layer.

Chlorhexidine as an enzyme inhibitor

Originally, the collagen matrix exposed with acidetching was thought to be protected by the polymer-ized adhesive enveloping the fibrils. However, dentincontains several enzymes that in concert can degradepractically all extracellular matrix proteins, includingtype I collagen and other dentinal matrix components.Most of the identified enzymes belong to the family ofmatrix metalloproteinases (MMPs), of which at leastMMP-8 (collagenase), MMP-2 and -9 (gelatinases),MMP-3 (stromelysin), and MMP-20 (enamelysin) arepresent in dentin (170,198–202). Recent studies havealso demonstrated another group of enzymes, cysteinecathepsins, in human dentin (203,204). For a detailed

description of the presence and roles of these enzymesin dentin, please see the article by Mazzoni and othersin this issue.

In mineralized dentin, enzyme activity is preventedby the mineral component, but once liberated andactivated by acid-etching, it can slowly degrade thecollagen fibrils even in the resin-infiltrated hybridlayers (205–208) (Fig. 5). As well, the etch-and-rinseadhesives (63,209) and self-etch adhesives (210,211)can activate dentinal MMPs. Even though the func-tional mechanisms of dentin matrix enzymes are notexactly known, it is believed that collagen is firstbroken down to 3⁄4 and 1⁄4 fragments by MMP-8, a truecollagenase. The resulting product, called gelatin, isfurther degraded by the gelatinases MMP-2 and -9.However, the interplay between MMPs and cysteinecathepsins in dentin may be much more complex, assuggested by Nascimento and co-authors (203) in thesupplemental Appendix for the manuscript. Whateverthe mechanism, the conversion of insoluble collagenfibrils to soluble fragments leads to the loss of attach-ment of the hybrid layer with the collagen anchoredinto the underlying mineralized dentin (Fig. 5). Thistime-dependent loss of resin–dentin adhesion has beenrepeatedly demonstrated (8,197,212).

Ever since the discovery that dentin-bound enzymesdegrade exposed dentinal collagen (56), research hassearched for ways to improve the bond strength dura-bility by inhibiting the enzymes. The most interest hasbeen directed toward chlorhexidine, which is knownto inhibit purified MMP-8, -2, and -9 (213) and alsoto effectively reduce dentin matrix enzyme activity(200,214–216). Both in vitro and in vivo studies havedemonstrated that hybrid layer MMP inhibition withchlorhexidine is an effective approach to improving thedurability of the resin–dentin bond, both with etch-and-rinse adhesives (64,205,206,208,217–221) andalso with self-etch adhesives when used in high enoughconcentrations (219,222). In general, treating acid-etched dentin with chlorhexidine demonstrates 1.9%monthly loss in bond strength compared to approxi-mately 5% loss in no-treatment groups (223). Chlor-hexidine also effectively eliminates the reduction ofbond strength in vivo: after 14 months in clinicalservice, the bond strength of chlorhexidine-treatedcomposite fillings was reduced only 1.5% from theimmediate bond strength, the respective loss in thecontrol group being 35% (206). Currently, the useof chlorhexidine during the bonding procedure to

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increase the longevity of dentin bond strength isrecommended for clinical practice (223–225).

Other approaches to improvedentin bonding

Even though chlorhexidine has been proven to effec-tively improve the long-term bond strength both

in vitro and in vivo, it still requires an additionalstep during the bonding procedure. Therefore, otherapproaches to improve the longevity of dentinbonding have also been studied with the goal offinding more practical or even more durable meansto preserve the hybrid layer integrity (197). Theseinclude at least ethanol wet-bonding (58,60,226–228), the use of MMP-inhibiting monomers (229) orother MMP inhibitors (61,65,230), increasing hybridlayer collagen cross-linking prior to adhesive applica-tion (231–234), and the biomimetic remineralizationof the hybrid layer (235–237).

At present, ethanol wet-bonding is perhaps the mostpromising approach, resulting in good preservation ofthe hybrid layer and high long-term bond strengthvalues. The promising findings may at least partially bedue to the reduced hydrolytic degradation of thehybrid layer collagen (223,224,226), but also to thebetter encapsulation of collagen matrix and the pres-ence of more durable hydrophobic adhesive in thehybrid layer (224). However, the original protocolrequires several steps and is too time-consuming tobe acceptable in clinical work. More recently, Mansoand others were able to demonstrate that the ethanolwet-bonding concept can be used in conjunctionwith commercially available adhesives within a clini-cally acceptable time (Manso et al., unpublishedresults). Ultimately, further research is required todetermine a simple, reliable, and clinically practicalapplication protocol (227). The efficacy and theadvantages of the use of MMP-inhibiting monomersand other MMP inhibitors compared to the useof chlorhexidine still needs to be demonstrated.Increased cross-linking and improving hybridizationby increasing the collagen matrix stiffness (232,233)may improve both immediate and long-term bondstrength (232,234), and the increased durability mayat least partially be due to MMP inhibition (224,232,234). As with ethanol wet-bonding, current applica-tions with biocompatible and non-toxic cross-linkingagents are time-consuming and thus faster and simplerprotocols are needed before introducing their use inclinical procedures (224). Biomimetic remineraliza-tion, aimed at returning to the mineralized state of thecollagen matrix within the hybrid layer, is biologicallyvery attractive and has been shown to result in goodpreservation of bond strength (238). However, theapproach is highly experimental, and clinical applica-tions may still be far away.

Fig. 5. Schematic representation of the firmness of thehybrid layer over time. (a) Immediately after bonding,the exposed dentinal collagen matrix, firmly attached tomineralized dentin (MD) underneath, is mostly embed-ded with the adhesive, forming the hybrid layer (HL).At least with etch-and-rinse adhesives and most likelyalso with self-etch adhesives, the layer of more or lessdemineralized, but not adhesive-embedded, collagenmatrix between the hybrid layer and mineralized dentinforms the so-called nanoleakage (NL) area. The adhesivelayer (AL: usually more hydrophobic layer than that inthe hybrid layer) forms the chemical bond with thecompostite resin (CR). (b) The time-dependent degra-dation of the collagen fibrils in the nanoleakage layerand hybrid layer itself lead to the loss of collagen in thehybrid layer, resulting in the loss of the firm anchorageof the hybrid layer, and thus the whole restorative com-posite to the dentin underneath.

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Bonding to root dentin

The major goals of successful endodontic therapy aredisinfection and perfect obliteration of the root canalspace with an inert filling material to create an optimalseal with the tooth structure. Although predictableclinical results have been reported with the use ofnon-bonding root canal sealer/filling materials (239,240), there has been a natural request for alternativematerials that bond simultaneously to root canal wallsand filling materials, in order to achieve compactmonoblock sealing. Notwithstanding, adhesive proce-dures have become popular for root canal obturation,pulp chamber sealing, cementation of posts and cores,and other endodontic therapies. However, successfulbonding to root dentin can be regarded as one of thegreatest challenges in adhesive dentistry. This is, inpart, due to the limited knowledge regarding how thestructural and physiological characteristics of this par-ticular substrate affect the bonding mechanism of con-temporary methacrylate resin-based materials that areused for endodontic applications.

Despite the fact that the principles of adhesion tocoronal dentin can also be applied to root dentin,specific variations on dentin structure (241–243), localmorphology (10,244,245), and physiological shiftsdue to aging and/or pathological processes (16) playimportant roles in the performance of dental adhesivesand the quality of the resultant bonded interfaces.

Morphological, compositional, and structural par-ticularities regarding dentin in sclerotic non-cariouscervical lesions (NCCL), localized on the coronalthird of dental roots, were previously addressed in thisreview as imposing a relative barrier to achieving aperfect bonding procedure. This section will explorethe multiple aspects that can be involved with thesuccess/failure of the interaction between adhesivematerials, specifically the methacrylate-based resinsand the intraradicular dentin (i.e. root canal dentin) ofnon-vital teeth.

As with any other dental hard tissue, the prevailingmechanism to bond methacrylate-based resins tointraradicular dentin is dependent on micromechanicalretention of these resins in the treated/primed tissue,regardless if the bonding procedure is the filling/obturation of root canals or the cementation of postsand cores. Because of the limited vision and access,predominance of sclerotic dentin along the apical partof the root canal (245), regional differences in bond

strength (123,246), presence of a thick smear layer(247,248), and high cavity configuration factor(C-factor) (246,249,250), the achievement ofperfect infiltration and micromechanical retention ofmethacrylate-based resins in the root canal environ-ment remains a clinical challenge.

Similarly to coronal dentin, intraradicular dentin is anon-homogeneous tissue characterized by the pres-ence of tubules extending outward from the pulpcavity to the tooth (245). Studies that have morpho-logically analyzed human intraradicular dentin did notreport significant differences in tubule density andtubule cross-sectional area between the cervical andmiddle thirds of root dentin (244,251). In addition,these studies demonstrated only minor morphologicaldifferences between deep coronal and cervical in-traradicular dentin, which suggests that cervical andmiddle intradicular dentin should behave similarly tocervical coronal dentin (i.e. deep coronal dentin) withrespect to bonding substrates. Despite such apparentmorphological and compositional similarities (244,251), the bond strength to intraradicular dentinbonded with methacrylate-based resins has beenmostly reported as being extremely variable along theroot canal (246,252–254) and significantly lower thanthat observed for coronal dentin (245,246,250,253,255,256).

A noticeable morphological characteristic that isreported to be exclusively part of intraradicular dentinis the presence of convex, dome-shaped projections,called calcospherites, which produce globular undula-tions along the entire root canal surface (251). Theinfluence of calcospherites on the bonding perfor-mance of methacrylate-based resins to intraradiculardentin has not been sufficiently investigated, butas these projections create an irregular and non-homogenous surface to dentin, they may contribute tomaking intraradicular dentin a less responsive substrate(or a more challenging one) for bonding maneuvers.For instance, there is evidence indicating that in-adequate dentin–resin hybridization might occur innon-instrumented calcospherite-containing dentinwhen sodium hypochlorite (NaOCl) is used as theonly active root canal irrigant (235).

Another limiting entity affecting the adhesion tointraradicular dentin is the presence of the smear layer.The smear layer has been defined as any debris, calcificin nature, produced by instrumentation of dentin,enamel, or cementum (257) or as a contaminant (258)

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that hampers the interaction of the underlying tissueswith restorative/filling materials. On radicular dentin,the morphological features, composition, and thick-ness of the smear layer are determined by the type ofendodontic instrument used, the method of irrigation,and the tooth substrate from which it is formed(247,248).

As previously mentioned, two bonding strategies arecurrently employed to bond methacrylate-based resinsto dentin and both approaches have a paradigmaticrelationship with the smear layer. With the etch-and-rinse approach, the acid-etching and rinsing stepstotally remove the smear layer prior to the bondingstep, while for the self-etching systems, the smear layeris partially dissolved and incorporated in the hybridizedcomplex. The more acidic and aggressive the condi-tioner, the more completely the smear layer is removed(259). While the modification and incorporation ofsmear layer into hybrid layers by using self-etchingadhesive systems can have clinical advantages whenconsidering the bonding to coronal dentin, such as lesstechnique sensitivity (260) and less post-operative sen-sitivity (261,262), for endodontic therapy, the perma-nence of smear layer might not only represent a barrierto achieving effective bonding to instrumented canalwalls (263,264), but it may also work as a bacterialdeposit that puts the prognosis of root canal treatmentat risk. Thus, in Endodontics, it is prudent to removethe smear layer from infected root canals to allow forbetter infiltration of intraradicular medications into thedentinal tubules (265) and further improve tissuebonding capabilities (265–267).

For some years now, a line of methacrylate resin-based sealers has been specifically designed for endo-dontic applications. For better elucidation on thecharacteristics of each system available on the market,we advise reading the review by Kim et al. (235).Taking into consideration that self-etching systems areless technique-sensitive and more user-friendly (i.e.reduced application steps), the most recently intro-duced bondable root canal sealers (180,268,269)belong to the category of “bonding system.” Recentresults that report the limited aggressiveness of con-temporary self-etch and self-adhesive resin composites(270–272) raised similar concerns on the potential ofself-etching and self-adhesive sealers to truly hybridizeintraradicular dentin. Indeed, it has been shown thatthe true etching capability of self-etching and self-adhesive endodontic sealers is a critical factor that

affects the bonding effectiveness to intraradiculardentin (228,235).

Manufacturers of self-etching methacrylate resin-based endodontic sealers recommend the removal ofthe smear layer with EDTA, assuring the relevanceof this step to reduce leakage and improve the seal offilled canals (235). Thus, the retention mechanismssuggested by the manufacturers of methacrylate resin-based endodontic sealers (i.e. hybridization of intratu-bular dentin and resin tag formation) are likely to beenhanced by the combined dentin demineralizationresultant from EDTA (228) and the sealer system(235).

In addition to the “primary” smear layer created byinstrumentation of the root canal walls, when clinicallyindicated, the subsequent preparation for post cemen-tation using “post drills” resulted in an even thickersmear layer composed of previous debris supple-mented with fragments of sealer/gutta-percha rem-nants that were shown to significantly affect thepenetration and chemical action of the agents used tobond fiber posts to root walls (266,273). Moreover,at this stage of the endodontic treatment, onlyminimal irrigation can be performed inside the endo-dontic canal (274). Retention of methacrylate-basedcements to intraradicular dentin may be improvedby EDTA pre-treatment (275). Other protocols havealso recommended a combination of ultrasonic instru-mentation with EDTA pre-treatment (276) or eventhe use of stronger conditioners such as phosphoricacid (277). The resultant bond strength will, however,be dependent on the residual effect of the dentinalirrigant/disinfectant (278) as well as on the bondingstrategy selected (279).

Shrinkage stresses associated with polymerizationof methacrylate-based resins are higher in low-filled,lower viscosity resin cements and root canal sealersthan in highly filled resin composites (280–282).During polymerization of methacrylate-based resins,the intermolecular spaces between the resin monomersare reduced, generating sufficient shrinkage stresses todebond the material from dentin, thereby decreasingretention and increasing leakage (250). Undoubtedly,amongst all concerns associated with bonding meth-acrylate based-resins to intraradicular dentin, the chal-lenge of achieving a balanced relief for the shrinkagestresses of these resinous materials seems to be themost limiting factor toward obtaining a perfect anddurable sealing of the root canal apparatus (250).

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All of the factors previously discussed can, inconcert, affect the bonding effectiveness to intra-radicular dentin. Ultimately, there is a general consen-sus that the use of methacrylate-based resins forsealing intraradicular dentin has not brought a para-digm shift in the strategy toward achieving perfectsealing of the root canal system (283–290). One of themajor focuses of current root canal therapy has reliedon the attempt to replace the non-bonding fillingsystems with resin-based materials that can supposedlyestablish intimate contact with intraradicular dentin,thereby reinforcing the tooth structure and preventingroot recontamination. However, this achievementhas not been fully supported, at least considering theresults of a number of ex vivo studies (283–293). Inaddition, very few of the limited clinical outcome trialshave included a control group so that the advantagesof these new materials over conventional non-bondingmaterials could be supported (235). In fact, the lackof evidence-based clinical information on the perfor-mance of some of these endodontic resin-based mate-rials should foment professionals to think carefullyabout whether or not and when to adopt resin mate-rials to seal intraradicular dentin.

Cementation of postsRemoval of the sealer and gutta-percha from the root-filled teeth is required for post-space preparation (294,295). The resulting debris produced leads to an increaseof leakage (296) and occlusion of dentinal tubules(297), thereafter impairing adequate bonding of thefiber post into the root canal (298). As discussed above,the removal of the smear layer plays a critical role in thequality of the bonding to the root canal. Despite the useof ultrasonic instruments, chemical agents, and lasers,the complete removal of the smear layer in the apicalthird of the root space remains unpredictable. A com-bination of chemical agents and ultrasonic instru-ments via acoustic streaming could significantly improvesmear layer removal after endodontic instrumentation.However, the use of EDTA alone may result in incom-plete debris removal; similarly, the use of ultrasonicswithout the aid of chemical agents produces packing ofdebris into the dentin tubules (299). There is generalagreement that the removal of smear layers generatedduring root canal instrumentation is more efficient inthe coronal and middle thirds than in the apical part ofthe root (300,301).

Because the efficacy of the bonding has a directcorrelation with dentinal tubule characteristics, it isimportant to make a statement regarding the apicalthird of the root. Mjör et al. reported that the apicalthird of the root has the most disparity in morphologyand includes the following: accessory root canals;areas of resorption and repaired resorptions; occa-sional attached, embedded, and free pulp stones;varied quantities of asymmetrical secondary dentin;and cementum-like tissue lining the apical root canalwall (302). Overall, the diverse morphology exhibitedby root dentin may make coaxing methacrylate resinbonding into the root canal an endless challenge.

The role of friction as a mean of retention of postscemented into the root canal has been raised (245,303,304). While it is not yet clear how much the resistance todislodgement of fiber posts from the root canal is theresult of bonding or friction, it is remarkable that postscemented with zinc phosphate presented a resistanceto dislodgement similar to posts cemented with a com-bination of adhesives and resin cements (305,306).Because adhesion does not seem to play a crucial rolein the retention of posts, clinicians may prefer theuser-friendliness of self-adhesive resin cements.

Concluding remarksBonding to dentin remains a major challenge in adhe-sive dentistry. The dynamic substrate characteristicsthat change regionally with age and according toseveral intrinsic and extrinsic stimuli make bondingattempts to dentin far from standard and poorly pre-dictable. Adhesive systems have evolved to better copewith these challenging nuances of dentin, but resin–dentin bonds are still less predictable and less reliablethan resin–enamel bonds. Recent research has exam-ined alternative methods to increase the durability ofresin–dentin bonds. These include the use of anti-enzymatic agents such as chlorhexidine, benzalconiumchloride, galardin, and ethanol in the ethanol wet-bonding technique, which also improves the durabilityby allowing relatively more hydrophobic resins to bebonded to dentin. Collagen cross-linking agentsand procedures have also been introduced as ways tostabilize collagen fibrils, thus increasing resistance toenzymatic degradation over time. However, these arenot yet applicable in routine clinical practice. Rootcanal dentin seems to be an even harsher environmentfor effective bonding to be accomplished. In addition

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to the obstacles encountered when bonding to coronaldentin, bonding to root canal faces the challengesimposed by the shrinkage stresses of resin-basedbonding and luting agents. How much the limitationsin bonding to dentin truly result in or are caused byclinical procedural failures remains to be determined.

References

1. Pashley DH, Depew DD, Galloway SE. Microleakagechannels: scanning electron microscopic observation.Oper Dent 1989: 14: 68–72.

2. Perdigão J. Dentin bonding—variables related to theclinical situation and the substrate treatment. DentMater 2010: 26: e24–e37.

3. Spencer P, Ye Q, Park J, Topp EM, Misra A, MarangosO, Wang Y, Bohaty BS, Singh V, Sene F, Eslick J,Camarda K, Katz JL. Adhesive/dentin interface: theweak link in the composite restoration. Ann BiomedEng 2010: 38: 1989–2003.

4. Van Meerbeek B, Yoshihara K, Yoshida Y, Mine A, DeMunck J, Van Landuyt KL. State-of-the-art of self-etchadhesives. Dent Mater 2011: 27: 17–28.

5. Van Meerbeek B, Peumans M, Poitevin A, Mine A,Van Ende A, Neves A, De Munck J. Relationshipbetween bond-strength tests and clinical outcomes.Dent Mater 2010: 26: e100–e121.

6. Cardoso MV, Neves A, Mine A, Coutinho E, VanLanduyt K, De Munck J, Van Meerbeek B. Currentaspects on bonding effectiveness and stability in adhe-sive dentistry. Aust Dent J 2011: 56(Suppl 1): 31–44.

7. Carvalho RM, Manso AP, Geraldeli S, Tay FR, PashleyDH. Durability of bonds and clinical success of adhe-sive restorations. Dent Mater 2012: 28: 72–86.

8. Pashley DH, Tay FR, Breschi L, Tjäderhane L, Car-valho RM, Carrilho M, Tezvergil-Mutluay A. State-of-the-art etch-and-rinse adhesives. Dent Mater 2011:27: 1–16.

9. Carvalho RM, Yoshiyama M, Pashley EL, Pashley DH.In vitro study on the dimensional changes of humandentine after demineralization. Arch Oral Biol 1996:41: 369–377.

10. Garberoglio R, Brannstrom M. Scanning electronmicroscopic investigation of human dentinal tubules.Arch Oral Biol 1976: 21: 355–362.

11. Nakabayashi N, Pashley DH. Hybridization of DentalHard Tissues. Tokyo, Japan: Quintessence PublishingCo., 1998.

12. Pashley DH, Carvalho RM. Dentine permeability anddentine adhesion. J Dent 1997: 25: 355–372.

13. Giannini M, Carvalho RM, Martins LR, Dias CT,Pashley DH. The influence of tubule density and areaof solid dentin on bond strength of two adhesivesystems to dentin. J Adhes Dent 2001: 3: 315–324.

14. Kinney JH, Balooch M, Marshall SJ, Marshall GW Jr,Weihs TP. Atomic force microscope measurements of

the hardness and elasticity of peritubular and inter-tubular human dentin. J Biomech Eng 1996: 118:133–135.

15. Kinney JH, Marshall SJ, Marshall GW. The mechanicalproperties of human dentin: a critical review andre-evaluation of the dental literature. Crit Rev OralBiol Med 2003: 14: 13–29.

16. Marshall GW Jr, Marshall SJ, Kinney JH, Balooch M.The dentin substrate: structure and properties relatedto bonding. J Dent 1997: 25: 441–458.

17. Smith DC, Cooper WE. The determination of shearstrength. A method using a micro-punch apparatus.Br Dent J 1971: 130: 333–337.

18. Sano H, Ciucchi B, Matthews WG, Pashley DH.Tensile properties of mineralized and demineralizedhuman and bovine dentin. J Dent Res 1994: 73: 1205–1211.

19. Watanabe LG, Marshall GW Jr, Marshall SJ. Dentinshear strength: effects of tubule orientation and intra-tooth location. Dent Mater 1996: 12: 109–115.

20. Carvalho RM, Fernandes CA, Villanueva R, Wang L,Pashley DH. Tensile strength of human dentin as afunction of tubule orientation and density. J AdhesDent 2001: 3: 309–314.

21. Sano H, Yoshikawa T, Pereira PN, Kanemura N, Mori-gami M, Tagami J, Pashley DH. Long-term durabilityof dentin bonds made with a self-etching primer, invivo. J Dent Res 1999: 78: 906–911.

22. Fuentes V, Ceballos L, Osorio R, Toledano M,Carvalho RM, Pashley DH. Tensile strength andmicrohardness of treated human dentin. Dent Mater2004: 20: 522–529.

23. Giannini M, Soares CJ, de Carvalho RM. Ultimatetensile strength of tooth structures. Dent Mater 2004:20: 322–329.

24. Inoue S, Pereira PN, Kawamoto C, Nakajima M,Koshiro K, Tagami J, Carvalho RM, Pashley DH, SanoH. Effect of depth and tubule direction on ultimatetensile strength of human coronal dentin. Dent MaterJ 2003: 22: 39–47.

25. Inoue T, Nishimura F, Debari K, Kou K, Miyazaki T.Fatigue and tensile properties of radicular dentin sub-strate. J Biomech 2011: 44: 586–592.

26. Zaslansky P, Zabler S, Fratzl P. 3D variations inhuman crown dentin tubule orientation: a phase-contrast microtomography study. Dent Mater 2010:26: e1–e10.

27. Dimitriu B, Varlan C, Suciu I, Varlan V, Bodnar D.Current considerations concerning endodonticallytreated teeth: alteration of hard dental tissues and bio-mechanical properties following endodontic therapy.J Med Life 2009: 2: 60–65.

28. Goldberg M, Kulkarni AB, Young M, Boskey A.Dentin: structure, composition and mineralization.Front Biosci (Elite Ed) 2011: 3: 711–735.

29. Hosoya Y, Tay FR, Miyakoshi S, Pashley DH. Hard-ness and elasticity of caries-affected and sound primarytooth dentin bonded with 4-META one-step self-etchadhesives. Am J Dent 2008: 21: 223–228.

Carvalho et al.

78

Page 18: Dentina Como Sustrato

30. Wei S, Sadr A, Shimada Y, Tagami J. Effect of caries-affected dentin hardness on the shear bond strength ofcurrent adhesives. J Adhes Dent 2008: 10: 431–440.

31. Nakajima M, Sano H, Burrow MF, Tagami J, Yoshi-yama M, Ebisu S, Ciucchi B, Russell CM, Pashley DH.Tensile bond strength and SEM evaluation of caries-affected dentin using dentin adhesives. J Dent Res1995: 74: 1679–1688.

32. Nakabayashi N, Kojima K, Masuhara E. The promo-tion of adhesion by the infiltration of monomers intotooth substrates. J Biomed Mater Res 1982: 16: 265–273.

33. Van Meerbeek B, Inokoshi S, Braem M, Lambrechts P,Vanherle G. Morphological aspects of the resin–dentininterdiffusion zone with different dentin adhesivesystems. J Dent Res 1992: 71: 1530–1540.

34. Pashley DH, Ciucchi B, Sano H, Horner JA. Perme-ability of dentin to adhesive agents. Quintessence Int1993: 24: 618–631.

35. Goldberg M, Lasfargues JJ. Pulpo–dentinal complexrevisited. J Dent 1995: 23: 15–20.

36. Perdigão J, Lambrechts P, Van Meerbeek B, Braem M,Yildiz E, Yücel T, Vanherle G. The interaction of adhe-sive systems with human dentin. Am J Dent 1996: 9:167–173.

37. Carvalho RM, Mendonçca JS, Santiago SL, SilveiraRR, Garcia FC, Tay FR, Pashley DH. Effects ofHEMA/solvent combinations on bond strength todentin. J Dent Res 2003: 82: 597–601.

38. Garcia FC, Otsuki M, Pashley DH, Tay FR, CarvalhoRM. Effects of solvents on the early stage stiffeningrate of demineralized dentin matrix. J Dent 2005: 33:371–377.

39. Maciel KT, Carvalho RM, Ringle RD, Preston CD,Russell CM, Pashley DH. The effects of acetone,ethanol, HEMA, and air on the stiffness of humandecalcified dentin matrix. J Dent Res 1996: 75:1851185–1851188.

40. Pashley DH, Agee KA, Carvalho RM, Lee KW, TayFR, Callison TE. Effects of water and water-free polarsolvents on the tensile properties of demineralizeddentin. Dent Mater 2003: 19: 347–352.

41. Pashley DH, Agee KA, Nakajima M, Tay FR, CarvalhoRM, Terada RS, Harmon FJ, Lee WK, RueggebergFA. Solvent-induced dimensional changes in EDTA-demineralized dentin matrix. J Biomed Mater Res2001: 56: 273–281.

42. Pashley DH, Carvalho RM, Tay FR, Agee KA, LeeKW. Solvation of dried dentin matrix by water andother polar solvents. Am J Dent 2002: 15: 97–102.

43. Kanca J 3rd. Improving bond strength through acidetching of dentin and bonding to wet dentin surfaces.J Am Dent Assoc 1992: 123: 35–43.

44. Nakaoki Y, Nikaido T, Pereira PN, Inokoshi S, TagamiJ. Dimensional changes of demineralized dentintreated with HEMA primers. Dent Mater 2000: 16:441–446.

45. Reis A, Loguercio AD, Azevedo CL, de Carvalho RM,Singer M, Grande RH. Moisture spectrum of deminer-

alized dentin for adhesive systems with differentsolvent bases. J Adhes Dent 2003: 5: 183–192.

46. Reis A, Loguercio AD, Carvalho RM, Grande RH.Durability of resin dentin interfaces: effects of surfacemoisture and adhesive solvent component. Dent Mater2004: 20: 669–676.

47. Van Meerbeek B, Yoshida Y, Lambrechts P, VanherleG, Duke ES, Eick JD, Robinson SJ. A TEM study oftwo water-based adhesive systems bonded to dry andwet dentin. J Dent Res 1998: 77: 50–59.

48. Spencer P, Wang Y. Adhesive phase separation atthe dentin interface under wet bonding conditions.J Biomed Mater Res 2002: 62: 447–456.

49. Tay FR, Gwinnett JA, Wei SH. Micromorphologicalspectrum from overdrying to overwetting acid-conditioned dentin in water-free acetone-based,single-bottle primer/adhesives. Dent Mater 1996: 12:236–244.

50. Yiu CK, Pashley EL, Hiraishi N, King NM, GoracciC, Ferrari M, Carvalho RM, Pashley DH, Tay FR.Solvent and water retention in dental adhesiveblends after evaporation. Biomaterials 2005: 26:6863–6872.

51. Jacobsen T, Soderholm KJ. Some effects of water ondentin bonding. Dent Mater 1995: 11: 132–136.

52. Wang Y, Spencer P, Yao X, Brenda B. Effect of solventcontent on resin hybridization in wet dentin bonding.J Biomed Mater Res A 2007: 82: 975–983.

53. Wang Y, Spencer P, Yao X, Ye Q. Effect of coinitiatorand water on the photoreactivity and photopolymeri-zation of HEMA/camphoquinone-based reactantmixtures. J Biomed Mater Res A 2006: 78: 721–728.

54. Misra A, Spencer P, Marangos O, Wang Y, Katz JL.Micromechanical analysis of dentin/adhesive interfaceby the finite element method. J Biomed Mater Res BAppl Biomater 2004: 70: 56–65.

55. Misra A, Spencer P, Marangos O, Wang Y, Katz JL.Parametric study of the effect of phase anisotropy onthe micromechanical behaviour of dentin–adhesiveinterfaces. J R Soc Interface 2005: 2: 145–157.

56. Pashley DH, Tay FR, Yiu C, Hashimoto M, Breschi L,Carvalho RM, Ito S. Collagen degradation by host-derived enzymes during aging. J Dent Res 2004: 83:216–221.

57. Carrilho MR, Tay FR, Pashley DH, Tjäderhane L,Carvalho RM. Mechanical stability of resin–dentinbond components. Dent Mater 2005: 21: 232–241.

58. Pashley DH, Tay FR, Carvalho RM, Rueggeberg FA,Agee KA, Carrilho M, Donnelly A, García-Godoy F.From dry bonding to water-wet bonding to ethanol-wet bonding. A review of the interactions betweendentin matrix and solvated resins using a macromodelof the hybrid layer. Am J Dent 2007: 20: 7–20.

59. Sauro S, Watson TF, Mannocci F, Miyake K, HuffmanBP, Tay FR, Pashley DH. Two-photon laser confocalmicroscopy of micropermeability of resin–dentinbonds made with water or ethanol wet bonding.J Biomed Mater Res B Appl Biomater 2009: 90: 327–337.

Dentin bonding

79

Page 19: Dentina Como Sustrato

60. Sadek FT, Castellan CS, Braga RR, Mai S, TjäderhaneL, Pashley DH, Tay FR. One-year stability of resin–dentin bonds created with a hydrophobic ethanol-wetbonding technique. Dent Mater 2010: 26: 380–386.

61. Tezvergil-Mutluay A, Agee KA, Hoshika T, UchiyamaT, Tjäderhane L, Breschi L, Mazzoni A, ThompsonJM, McCracken CE, Looney SW, Tay FR, PashleyDH. Inhibition of MMPs by alcohols. Dent Mater2011: 27: 926–933.

62. Ye Q, Spencer P, Wang Y, Misra A. Relationship ofsolvent to the photopolymerization process, proper-ties, and structure in model dentin adhesives. J BiomedMater Res A 2007: 80: 342–350.

63. Mazzoni A, Pashley DH, Nishitani Y, Breschi L, Man-nello F, Tjäderhane L, Toledano M, Pashley EL, TayFR. Reactivation of inactivated endogenous proteo-lytic activities in phosphoric acid-etched dentineby etch-and-rinse adhesives. Biomaterials 2006: 27:4470–4476.

64. Stanislawczuk R, Amaral RC, Zander-Grande C,Gagler D, Reis A, Loguercio AD. Chlorhexidine-containing acid conditioner preserves the longevityof resin–dentin bonds. Oper Dent 2009: 34: 481–490.

65. Tezvergil-Mutluay A, Mutluay MM, Gu LS, Zhang K,Agee KA, Carvalho RM, Manso A, Carrilho M, TayFR, Breschi L, Suh BI, Pashley DH. The anti-MMPactivity of benzalkonium chloride. J Dent 2011: 39:57–64.

66. Nakajima M, Okuda M, Ogata M, Pereira PN, TagamiJ, Pashley DH. The durability of a fluoride-releasingresin adhesive system to dentin. Oper Dent 2003: 28:186–192.

67. Shinohara MS, De Goes MF, Schneider LF, FerracaneJL, Pereira PN, Di Hipólito V, Nikaido T. Fluoride-containing adhesive: durability on dentin bonding.Dent Mater 2009: 25: 1383–1391.

68. Van Meerbeek B, De Munck J, Yoshida Y, Inoue S,Vargas M, Vijay P, Van Landuyt K, Lambrechts P,Vanherle G. Buonocore memorial lecture. Adhesionto enamel and dentin: current status and future chal-lenges. Oper Dent 2003: 28: 215–235.

69. De Munck J, Van Landuyt K, Peumans M, Poitevin A,Lambrechts P, Braem M, Van Meerbeek B. A criticalreview of the durability of adhesion to tooth tissue:methods and results. J Dent Res 2005: 84: 118–132.

70. Peumans M, Kanumilli P, De Munck J, Van LanduytK, Lambrechts P, Van Meerbeek B. Clinical effective-ness of contemporary adhesives: a systematic review ofcurrent clinical trials. Dent Mater 2005: 21: 864–881.

71. Tay FR, Kwong SM, Itthagarun A, King NM, Yip HK,Moulding KM, Pashley DH. Bonding of a self-etchingprimer to non-carious cervical sclerotic dentin: inter-facial ultrastructure and microtensile bond strengthevaluation. J Adhes Dent 2000: 2: 9–28.

72. Salz U, Mucke A, Zimmermann J, Tay FR, PashleyDH. pKa value and buffering capacity of acidic mono-mers commonly used in self-etching primers. J AdhesDent 2006: 8: 143–150.

73. Tay FR, Pashley DH. Aggressiveness of contemporaryself-etching systems. I: depth of penetration beyonddentin smear layers. Dent Mater 2001: 17: 296–308.

74. Tay FR, Sano H, Carvalho R, Pashley EL, Pashley DH.An ultrastructural study of the influence of acidityof self-etching primers and smear layer thickness onbonding to intact dentin. J Adhes Dent 2000: 2:83–98.

75. Wang Y, Spencer P. Physiochemical interactions at theinterfaces between self-etch adhesive systems anddentine. J Dent 2004: 32: 567–579.

76. Yoshida Y, Van Meerbeek B, Nakayama Y, SnauwaertJ, Hellemans L, Lambrechts P, Vanherle G, Wakasa K.Evidence of chemical bonding at biomaterial–hardtissue interfaces. J Dent Res 2000: 79: 709–714.

77. De Munck J, Vargas M, Iracki J, Van Landuyt K,Poitevin A, Lambrechts P, Van Meerbeek B. One-daybonding effectiveness of new self-etch adhesives tobur-cut enamel and dentin. Oper Dent 2005: 30:39–49.

78. Yoshida Y, Nagakane K, Fukuda R, Nakayama Y,Okazaki M, Shintani H, Inoue S, Tagawa Y, Suzuki K,De Munck J, Van Meerbeek B. Comparative study onadhesive performance of functional monomers. J DentRes 2004: 83: 454–458.

79. Inoue S, Koshiro K, Yoshida Y, De Munck J, NagakaneK, Suzuki K, Sano H, Van Meerbeek B. Hydrolyticstability of self-etch adhesives bonded to dentin. J DentRes 2005: 84: 1160–1164.

80. Abdalla AI, Feilzer AJ. Four-year water degradation ofa total-etch and two self-etching adhesives bonded todentin. J Dent 2008: 36: 611–617.

81. Abdalla AI, Elsayed HY, Garcia-Godoy F. Effect ofhydrostatic pulpal water pressure on microtensile bondstrength of self-etch adhesives to dentin. Am J Dent2008: 21: 233–238.

82. Carvalho RM, Chersoni S, Frankenberger R, PashleyDH, Prati C, Tay FR. A challenge to the conventionalwisdom that simultaneous etching and resin infiltra-tion always occurs in self-etch adhesives. Biomaterials2005: 26: 1035–1042.

83. Hashimoto M, Fujita S, Nagano F, Ohno H, Endo K.Ten-years degradation of resin–dentin bonds. Eur JOral Sci 2010: 118: 404–410.

84. Hashimoto M, Ohno H, Sano H, Kaga M, Oguchi H.In vitro degradation of resin–dentin bonds analyzedby microtensile bond test, scanning and transmissionelectron microscopy. Biomaterials 2003: 24: 3795–3803.

85. Inoue S, Van Meerbeek B, Abe Y, Yoshida Y, Lam-brechts P, Vanherle G, Sano H. Effect of remainingdentin thickness and the use of conditioner on micro-tensile bond strength of a glass-ionomer adhesive.Dent Mater 2001: 17: 445–455.

86. Lin A, McIntyre NS, Davidson RD. Studies on theadhesion of glass ionomer cements to dentin. J DentRes 1992: 71: 1836–1841.

87. Van Meerbeek B, Vargas M, Inoue S, Yoshida Y,Peumans M, Lambrechts P, Vanherle G. Adhesives and

Carvalho et al.

80

Page 20: Dentina Como Sustrato

cements to promote preservation dentistry. Oper Dent2001: 26: S119–S144.

88. Cardoso MV, Delmé KIM, Mine A, Neves AA,Coutinho E, De Moor RJG, Van Meerbeek B. Towardsa better understand of the adhesion mech-anism of resin-modified glass-ionomers by bonding todifferently prepared dentin. J Dent 2010: 38: 921–929.

89. Yiu CKY, Tay FR, King NM, Pashley DH, CarvalhoRM, Carrilho MRO. Interaction of resin-modifiedglass-ionomer cements with moist dentin. J Dent2004: 32: 521–530.

90. van Dijken JW. Retention of a resin-modified glassionomer adhesive in non-carious cervical lesions. A6-year follow-up. J Dent 2005: 33: 541–547.

91. Eick JD, Robinson SJ, Chappell RP, Cobb CM,Spencer P. The dentinal surface: its influence on den-tinal adhesion. Part III. Quintessence Int 1993: 24:571–582.

92. Eick JD, Wilko RA, Anderson CH, Sorensen SE. Scan-ning electron microscopy of cut tooth surfaces andidentification of debris by use of the electron micro-probe. J Dent Res 1970: 49: 1359–1368.

93. Pashley DH. Smear layer: overview of structure andfunction. Proc Finn Dent Soc 1992: 88(Suppl 1): 215–224.

94. Spencer P, Wang Y. X-ray photoelectron spectroscopy(XPS) used to investigate the chemical interactionof synthesized polyalkenoic acid with enamel and syn-thetic hydroxyapatite. J Dent Res 2001: 80: 1400–1401.

95. Wang Y, Spencer P. Analysis of acid-treated dentinsmear debris and smear layers using confocal Ramanmicrospectroscopy. J Biomed Mater Res 2002: 60:300–308.

96. Pashley DH. The effects of acid etching on the pulpo–dentin complex. Oper Dent 1992: 17: 229–242.

97. Ermis RB, De Munck J, Cardoso MV, Coutinho E,Van Landuyt KL, Poitevin A, Lambrechts P, VanMeerbeek B. Bond strength of self-etch adhesives todentin prepared with three different diamond burs.Dent Mater 2008: 24: 978–985.

98. Koibuchi H, Yasuda N, Nakabayashi N. Bonding todentin with a self-etching primer: the effect of smearlayers. Dent Mater 2001: 17: 122–126.

99. Kenshima S, Francci C, Reis A, Loguercio AD, FilhoLE. Conditioning effect on dentin, resin tags andhybrid layer of different acidity self-etch adhesivesapplied to thick and thin smear layer. J Dent 2006: 34:775–783.

100. Camps J, Pashley DH. Buffering action of humandentin in vitro. J Adhes Dent 2000: 2: 39–50.

101. Ogata M, Harada N, Yamaguchi S, Nakajima M,Pereira PN, Tagami J. Effects of different burs ondentin bond strengths of self-etching primer bondingsystems. Oper Dent 2001: 26: 375–382.

102. Sattabanasuk V, Vachiramon V, Qian F, ArmstrongSR. Resin–dentin bond strength as related to differ-ent surface preparation methods. J Dent 2007: 35:467–475.

103. Kenshima S, Reis A, Uceda-Gomez N, Tancredo LdeL, Filho LE, Nogueira FN, Loguercio AD. Effect ofsmear layer thickness and pH of self-etching adhesivesystems on the bond strength and gap formation todentin. J Adhes Dent 2005: 7: 117–126.

104. Oliveira SS, Pugach MK, Hilton JF, Watanabe LG,Marshall SJ, Marshall GW Jr. The influence of thedentin smear layer on adhesion: a self-etching primervs. a total-etch system. Dent Mater 2003: 19: 758–767.

105. do Amaral RC, Stanislawczuk R, Zander-Grande C,Michel MD, Reis A, Loguercio AD. Active applicationimproves the bonding performance of self-etch adhe-sives to dentin. J Dent 2009: 37: 82–90.

106. Loguercio AD, Stanislawczuk R, Mena-Serrano A,Reis A. Effect of 3-year water storage on the perfor-mance of one-step self-etch adhesives applied activelyon dentine. J Dent 2011: 39: 578–587.

107. Chan KM, Tay FR, King NM, Imazato S, Pashley DH.Bonding of mild self-etching primers/adhesives todentin with thick smear layers. Am J Dent 2003: 16:340–346.

108. Arola D, Reprogel RK. Effects of aging on themechanical behavior of human dentin. Biomaterials2005: 26: 4051–4061.

109. Kinney JH, Nalla RK, Pople JA, Breunig TM, RitchieRO. Age-related transparent root dentin: mineral con-centration, crystallite size, and mechanical properties.Biomaterials 2005: 26: 3363–3376.

110. Murray PE, Stanley HR, Matthews JB, Sloan AJ,Smith AJ. Age-related odontometric changes ofhuman teeth. Oral Surg Oral Med Oral Pathol OralRadiol Endod 2002: 93: 474–482.

111. Senawongse P, Otsuki M, Tagami J, Mjör I. Age-related changes in hardness and modulus of elasticityof dentine. Arch Oral Biol 2006: 51: 457–463.

112. Brackett WW, Tay FR, Looney SW, Ito S, Haisch LD,Pashley DH. The effect of subject age on the micro-tensile bond strengths of a resin and a resin-modifiedglass ionomer adhesive to tooth structure. Oper Dent2008: 33: 282–286.

113. Ozer F, Sengun A, Ozturk B, Say EC, Tagami J. Effectof tooth age on microtensile bond strength of twofluoride-releasing bonding agents. J Adhes Dent 2005:7: 289–295.

114. Tagami J, Nakajima M, Shono T, Takatsu T, HosodaH. Effect of aging on dentin bonding. Am J Dent1993: 6: 145–147.

115. Fuentes V, Toledano M, Osorio R, Carvalho RM.Microhardness of superficial and deep soundhuman dentin. J Biomed Mater Res A 2003: 66: 850–853.

116. Prati C, Pashley DH. Dentin wetness, permeability andthickness and bond strength of adhesive systems. Am JDent 1992: 5: 33–38.

117. Yoshiyama M, Carvalho R, Sano H, Horner J, BrewerPD, Pashley DH. Interfacial morphology and strengthof bonds made to superficial versus deep dentin. Am JDent 1995: 8: 297–302.

Dentin bonding

81

Page 21: Dentina Como Sustrato

118. Suzuki T, Finger WJ. Dentin adhesives: site of dentinvs. bonding of composite resins. Dent Mater 1988: 4:379–383.

119. Toledano M, Osorio R, Ceballos L, Fuentes MV,Fernandes CA, Tay FR, Carvalho RM. Microtensilebond strength of several adhesive systems to differentdentin depths. Am J Dent 2003: 16: 292–298.

120. Nakamichi I, Iwaku M, Fusayama T. Bovine teeth aspossible substitutes in the adhesion test. J Dent Res1983: 62: 1076–1081.

121. Pashley DH, Carvalho RM, Sano H, Nakajima M,Yoshiyama M, Shono Y, Fernandes CA, Tay F. Themicrotensile bond test: a review. J Adhes Dent 1999: 1:299–309.

122. Yoshiyama M, Carvalho RM, Sano H, Horner JA,Brewer PD, Pashley DH. Regional bond strengths ofresins to human root dentine. J Dent 1996: 24: 435–442.

123. Bouillaguet S, Ciucchi B, Jacoby T, Wataha JC,Pashley D. Bonding characteristics to dentin walls ofclass II cavities, in vitro. Dent Mater 2001: 17: 316–321.

124. Schüpbach P, Krejci I, Lutz F. Dentin bonding: effectof tubule orientation on hybrid-layer formation. Eur JOral Sci 1997: 105: 344–352.

125. Sattabanasuk V, Shimada Y, Tagami J. The bond ofresin to different dentin surface characteristics. OperDent 2004: 29: 333–341.

126. Phrukkanon S, Burrow MF, Tyas MJ. The effect ofdentine location and tubule orientation on the bondstrengths between resin and dentine. J Dent 1999: 27:265–274.

127. Tyas MJ, Anusavice KJ, Frencken JE, Mount GJ.Minimal intervention dentistry—a review. FDI Com-mission Project 1-97. Int Dent J 2000: 50: 1–12.

128. Neves AA, Coutinho E, Cardoso MV, Lambrechts P,Van Meerbeek B. Current concepts and techniquesfor caries excavation and adhesion to residual dentin.J Adhes Dent 2011: 13: 7–22.

129. Sattabanasuk V, Burrow MF, Shimada Y, Tagami J.Resin adhesion to caries-affected dentine after differentremoval methods. Aust Dent J 2006: 51: 162–169.

130. Ceballos L, Camejo DG, Victoria Fuentes M, OsorioR, Toledano M, Carvalho RM, Pashley DH. Micro-tensile bond strength of total-etch and self-etchingadhesives to caries-affected dentine. J Dent 2003: 31:469–477.

131. Yoshiyama M, Tay FR, Doi J, Nishitani Y, Yamada T,Itou K, Carvalho RM, Nakajima M, Pashley DH.Bonding of self-etch and total-etch adhesives tocarious dentin. J Dent Res 2002: 81: 556–560.

132. Say EC, Nakajima M, Senawongse P, Soyman M, OzerF, Tagami J. Bonding to sound vs. caries-affecteddentin using photo- and dual-cure adhesives. OperDent 2005: 30: 90–98.

133. Doi J, Itota T, Torii Y, Nakabo S, Yoshiyama M.Micro-tensile bond strength of self-etching primeradhesive systems to human coronal carious dentin.J Oral Rehabil 2004: 31: 1023–1028.

134. Yoshiyama M, Doi J, Nishitani Y, Itota T, Tay FR,Carvalho RM, Pashley DH. Bonding ability of adhe-sive resins to caries-affected and caries-infected dentin.J Appl Oral Sci 2004: 12: 171–176.

135. Inoue G, Tsuchiya S, Nikaido T, Foxton RM, TagamiJ. Morphological and mechanical characterization ofthe acid–base resistant zone at the adhesive–dentininterface of intact and caries-affected dentin. OperDent 2006: 31: 466–472.

136. Ito S, Saito T, Tay FR, Carvalho RM, Yoshiyama M,Pashley DH. Water content and apparent stiffnessof non-caries versus caries-affected human dentin.J Biomed Mater Res B Appl Biomater 2005: 72: 109–116.

137. Hsu KW, Marshall SJ, Pinzon LM, Watanabe L, SaizE, Marshall GW. SEM evaluation of resin-cariousdentin interfaces formed by two dentin adhesivesystems. Dent Mater 2008: 24: 880–887.

138. Yoshiyama M, Tay FR, Torii Y, Nishitani Y, Doi J, ItouK, Ciucchi B, Pashley DH. Resin adhesion to cariousdentin. Am J Dent 2003: 16: 47–52.

139. Wang Y, Spencer P, Walker MP. Chemical profile ofadhesive/caries-affected dentin interfaces using Ramanmicrospectroscopy. J Biomed Mater Res A 2007: 81:279–286.

140. Suppa P, Ruggeri A Jr, Tay FR, Prati C, Biasotto M,Falconi M, Pashley DH, Breschi L. Reduced antigenic-ity of type I collagen and proteoglycans in scleroticdentin. J Dent Res 2006: 85: 133–137.

141. Marshall GW, Habelitz S, Gallagher R, Balooch M,Balooch G, Marshall SJ. Nanomechanical properties ofhydrated carious human dentin. J Dent Res 2001: 80:1768–1771.

142. Ogawa K, Yamashita Y, Ichijo T, Fusayama T. Theultrastructure and hardness of the transparent layerof human carious dentin. J Dent Res 1983: 62: 7–10.

143. Daculsi G, LeGeros RZ, Jean A, Kerebel B. Possiblephysico-chemical processes in human dentin caries.J Dent Res 1987: 66: 1356–1359.

144. Spencer P, Wang Y, Katz JL, Misra A. Physicochemicalinteractions at the dentin/adhesive interface usingFTIR chemical imaging. J Biomed Opt 2005: 10:031104.

145. Erhardt MC, Toledano M, Osorio R, Pimenta LA.Histomorphologic characterization and bond strengthevaluation of caries-affected dentin/resin interfaces:effects of long-term water exposure. Dent Mater 2008:24: 786–798.

146. Yoshiyama M, Urayama A, Kimochi T, Matsuo T,Pashley DH. Comparison of conventional vs. self-etching adhesive bonds to caries-affected dentin. OperDent 2000: 25: 163–169.

147. Da Rosa Rodolpho PA, Donassollo TA, Cenci MS,Loguercio AD, Moraes RR, Bronkhorst EM, OpdamNJ, Demarco FF. 22-year clinical evaluation ofthe performance of two posterior composites withdifferent filler characteristics. Dent Mater 2011: 27:955–963.

Carvalho et al.

82

Page 22: Dentina Como Sustrato

148. Opdam NJ, Bronkhorst EM, Loomans BA, HuysmansMC. 12-year survival of composite vs. amalgam resto-rations. J Dent Res 2010: 89: 1063–1067.

149. van Dijken JW. A prospective 8-year evaluation of amild two-step self-etching adhesive and a heavily filledtwo-step etch-and-rinse system in non-carious cervicallesions. Dent Mater 2010: 26: 940–946.

150. Tay FR, Pashley DH. Resin bonding to cervical scle-rotic dentin: a review. J Dent 2004: 32: 173–196.

151. Kwong SM, Cheung GS, Kei LH, Itthagarun A,Smales RJ, Tay FR, Pashley DH. Micro-tensile bondstrengths to sclerotic dentin using a self-etching and atotal-etching technique. Dent Mater 2002: 18: 359–369.

152. Yoshiyama M, Sano H, Ebisu S, Tagami J, Ciucchi B,Carvalho RM, Johnson MH, Pashley DH. Regionalstrengths of bonding agents to cervical sclerotic rootdentin. J Dent Res 1996: 75: 1404–1413.

153. Eliguzeloglu E, Omurlu H, Eskitascioglu G, Belli S.Effect of surface treatments and different adhesiveson the hybrid layer thickness of non-carious cervicallesions. Oper Dent 2008: 33: 338–345.

154. van Dijken JW. Durability of three simplified adhesivesystems in Class V non-carious cervical dentin lesions.Am J Dent 2004: 17: 27–32.

155. Lopes GC, Baratieri CM, Baratieri LN, Monteiro S Jr,Cardoso Vieira LC. Bonding to cervical scleroticdentin: effect of acid etching time. J Adhes Dent 2004:6: 19–23.

156. ADA Council on Acceptance Program Guidelines.Dentin and enamel adhesive materials. J Am DentAssoc 2001: 132: 12.

157. Shellis RP. Structural organization of calcospherites innormal and rachitic human dentine. Arch Oral Biol1983: 28: 85–95.

158. Pascon FM, Kantovitz KR, Sacramento PA, Nobredos-Santos M, Puppin-Rontani RM. Effect of sodiumhypochlorite on dentine mechanical properties. Areview. J Dent 2009: 37: 903–908.

159. Sakae T, Mishima H, Kozawa Y. Changes in bovinedentin mineral with sodium hypochlorite treatment.J Dent Res 1988: 67: 1229–1234.

160. Zehnder M. Root canal irrigants. J Endod 2006: 32:389–398.

161. McComb D, Smith DC. A preliminary scanning elec-tron microscopic study of root canals after endodonticprocedures. J Endod 1975: 1: 238–242.

162. Sim TP, Knowles JC, Ng YL, Shelton J, Gulabivala K.Effect of sodium hypochlorite on mechanical proper-ties of dentine and tooth surface strain. Int Endod J2001: 34: 120–132.

163. Garcia-Godoy F, Loushine RJ, Itthagarun A, WellerRN, Murray PE, Feilzer AJ, Pashley DH, Tay FR.Application of biologically-oriented dentin bondingprinciples to the use of endodontic irrigants. Am JDent 2005: 18: 281–290.

164. Erdemir A, Ari H, Gungunes H, Belli S. Effect ofmedications for root canal treatment on bonding toroot canal dentin. J Endod 2004: 30: 113–116.

165. Lai SC, Mak YF, Cheung GS, Osorio R, Toledano M,Carvalho RM, Tay FR, Pashley DH. Reversal of com-promised bonding to oxidized etched dentin. J DentRes 2001: 80: 1919–1924.

166. Morris MD, Lee KW, Agee KA, Bouillaguet S, PashleyDH. Effects of sodium hypochlorite and RC-prep onbond strengths of resin cement to endodontic surfaces.J Endod 2001: 27: 753–757.

167. Nikaido T, Takano Y, Sasafuchi Y, Burrow MF,Tagami J. Bond strengths to endodontically-treatedteeth. Am J Dent 1999: 12: 177–180.

168. Perdigao J, Eiriksson S, Rosa BT, Lopes M, Gomes G.Effect of calcium removal on dentin bond strengths.Quintessence Int 2001: 32: 142–146.

169. Prasansuttiporn T, Nakajima M, Kunawarote S,Foxton RM, Tagami J. Effect of reducing agents onbond strength to NaOCl-treated dentin. Dent Mater2011: 27: 229–234.

170. Santos J, Carrilho M, Tervahartiala T, Sorsa T, BreschiL, Mazzoni A, Pashley D, Tay F, Ferraz C, TjäderhaneL. Determination of matrix metalloproteinases inhuman radicular dentin. J Endod 2009: 35: 686–689.

171. Vongphan N, Senawongse P, Somsiri W, HarnirattisaiC. Effects of sodium ascorbate on microtensile bondstrength of total-etching adhesive system to NaOCltreated dentine. J Dent 2005: 33: 689–695.

172. Weston CH, Ito S, Wadgaonkar B, Pashley DH.Effects of time and concentration of sodium ascorbateon reversal of NaOCl-induced reduction in bondstrengths. J Endod 2007: 33: 879–881.

173. Taniguchi G, Nakajima M, Hosaka K, Iwamoto N,Ikeda M, Foxton RM, Tagami J. Improving the effectof NaOCl pretreatment on bonding to caries-affecteddentin using self-etch adhesives. J Dent 2009: 37:769–775.

174. Attin T, Paqué F, Ajam F, Lennon AM. Review of thecurrent status of tooth whitening with the walkingbleach technique. Int Endod J 2003: 36: 313–329.

175. Ziebolz D, Helms K, Hannig C, Attin T. Efficacy andoral side effects of two highly concentrated tray-basedbleaching systems. Clin Oral Investig 2007: 11: 267–275.

176. Dahl JE, Pallesen U. Tooth bleaching—a criticalreview of the biological aspects. Crit Rev Oral BiolMed 2003: 14: 292–304.

177. Chng HK, Palamara JE, Messer HH. Effect of hydro-gen peroxide and sodium perborate on biomechanicalproperties of human dentin. J Endod 2002: 28: 62–67.

178. Kodaka T, Toko T, Debari K, Hisamitsu H, OhmoriA, Kawata S. Application of the environmental SEMin human dentin bleached with hydrogen peroxidein vitro. J Electron Microsc (Tokyo) 1992: 41: 381–386.

179. Joiner A. Review of the effects of peroxide on enameland dentine properties. J Dent 2007: 35: 889–896.

180. Babb BR, Loushine RJ, Bryan TE, Ames JM, CauseyMS, Kim J, Weller RN, Pashley DH, Tay FR. Bondingof self-adhesive (self-etching) root canal sealers toradicular dentin. J Endod 2009: 35: 578–582.

Dentin bonding

83

Page 23: Dentina Como Sustrato

181. Barcellos DC, Benetti P, Fernandes VV Jr, Valera MC.Effect of carbamide peroxide bleaching gel concentra-tion on the bond strength of dental substrates andresin composite. Oper Dent 2010: 35: 463–469.

182. Far C, Ruse ND. Effect of bleaching on fracturetoughness of composite-dentin bonds. J Adhes Dent2003: 5: 175–182.

183. Spyrides GM, Perdigao J, Pagani C, Araujo MA,Spyrides SM. Effect of whitening agents on dentinbonding. J Esthet Dent 2000: 12: 264–270.

184. Torneck CD, Titley KC, Smith DC, Adibfar A. Adhe-sion of light-cured composite resin to bleached andunbleached bovine dentin. Endod Dent Traumatol1990: 6: 97–103.

185. Cadenaro M, Breschi L, Antoniolli F, Mazzoni A, DiLenarda R. Influence of whitening on the degree ofconversion of dental adhesives on dentin. Eur J OralSci 2006: 114: 257–262.

186. Rueggeberg FA, Margeson DH. The effect of oxygeninhibition on an unfilled/filled composite system.J Dent Res 1990: 69: 1652–1658.

187. Bittencourt ME, Trentin MS, Linden MS, Arsati YB,Franca FM, Flório FM, Basting RT. Influence ofin situ postbleaching times on shear bond strength ofresin-based composite restorations. J Am Dent Assoc2010: 141: 300–306.

188. Cullen DR, Nelson JA, Sandrik JL. Peroxide bleaches:effect on tensile strength of composite resins. J ProsthetDent 1993: 69: 247–249.

189. Sulieman MA. An overview of tooth-bleaching tech-niques: chemistry, safety and efficacy. Periodontol 20002008: 48: 148–169.

190. Swift EJ Jr, Perdigão J. Effects of bleaching on teethand restorations. Compend Contin Educ Dent 1998:19: 815–820; quiz 822.

191. Teixeira EC, Turssi CP, Hara AT, Serra MC. Influenceof post-bleaching time intervals on dentin bondstrength. Braz Oral Res 2004: 18: 75–79.

192. Kaya AD, Turkun M. Reversal of dentin bonding tobleached teeth. Oper Dent 2003: 28: 825–829.

193. Kum KY, Lim KR, Lee CY, Park KH, Safavi KE, FouadAF, Spångberg LS. Effects of removing residual per-oxide and other oxygen radicals on the shear bondstrength and failure modes at resin–tooth interfaceafter tooth bleaching. Am J Dent 2004: 17: 267–270.

194. Muraguchi K, Shigenobu S, Suzuki S, Tanaka T.Improvement of bonding to bleached bovine toothsurfaces by ascorbic acid treatment. Dent Mater J2007: 26: 875–881.

195. Turkun M, Kaya AD. Effect of 10% sodium ascorbateon the shear bond strength of composite resin tobleached bovine enamel. J Oral Rehabil 2004: 31:1184–1191.

196. Freire A, Souza EM, de Menezes Caldas DB, Rosa EA,Bordin CF, de Carvalho RM, Vieira S. Reaction kinet-ics of sodium ascorbate and dental bleaching gel.J Dent 2009: 37: 932–936.

197. Liu Y, Tjäderhane L, Breschi L, Mazzoni A, Li N, MaoJ, Pashley DH, Tay FR. Limitations in bonding to

dentin and experimental strategies to prevent bonddegradation. J Dent Res 2011: 90: 953–968.

198. Martin-De Las Heras S, Valenzuela A, Overall CM.The matrix metalloproteinase gelatinase A in humandentine. Arch Oral Biol 2000: 45: 757–765.

199. Mazzoni A, Mannello F, Tay FR, Tonti GA, Papa S,Mazzotti G, Di Lenarda R, Pashley DH, Breschi L.Zymographic analysis and characterization of MMP-2and -9 forms in human sound dentin. J Dent Res 2007:86: 436–440.

200. Mazzoni A, Papa V, Nato F, Carrilho M, TjäderhaneL, Ruggeri A Jr, Gobbi P, Mazzotti G, Tay FR, PashleyDH, Breschi L. Immunohistochemical and biochemi-cal assay of MMP-3 in human dentine. J Dent 2011:39: 231–237.

201. Mazzoni A, Pashley DH, Tay FR, Gobbi P, Orsini G,Ruggeri A Jr, Carrilho M, Tjäderhane L, Di LenardaR, Breschi L. Immunohistochemical identification ofMMP-2 and MMP-9 in human dentin: correlativeFEI-SEM/TEM analysis. J Biomed Mater Res A 2009:88: 697–703.

202. Sulkala M, Tervahartiala T, Sorsa T, Larmas M, Salo T,Tjäderhane L. Matrix metalloproteinase-8 (MMP-8) isthe major collagenase in human dentin. Arch Oral Biol2007: 52: 121–127.

203. Nascimento FD, Minciotti CL, Geraldeli S, CarrilhoMR, Pashley DH, Tay FR, Nader HB, Salo T, Tjäder-hane L, Tersariol IL. Cysteine cathepsins in humancarious dentin. J Dent Res 2011: 90: 506–511.

204. Tersariol IL, Geraldeli S, Minciotti CL, NascimentoFD, Pääkkönen V, Martins MT, Carrilho MR, PashleyDH, Tay FR, Salo T, Tjäderhane L. Cysteine cathep-sins in human dentin–pulp complex. J Endod 2010:36: 475–481.

205. Carrilho MR, Carvalho RM, de Goes MF, di HipolitoV, Geraldeli S, Tay FR, Pashley DH, Tjäderhane L.Chlorhexidine preserves dentin bond in vitro. J DentRes 2007: 86: 90–94.

206. Carrilho MR, Geraldeli S, Tay F, de Goes MF, Car-valho RM, Tjäderhane L, Reis AF, Hebling J, MazzoniA, Breschi L, Pashley D. In vivo preservation of thehybrid layer by chlorhexidine. J Dent Res 2007: 86:529–533.

207. Garcia-Godoy F, Tay FR, Pashley DH, Feilzer A,Tjäderhane L, Pashley EL. Degradation of resin-bonded human dentin after 3 years of storage. Am JDent 2007: 20: 109–113.

208. Hebling J, Pashley DH, Tjäderhane L, Tay FR.Chlorhexidine arrests subclinical degradation ofdentin hybrid layers in vivo. J Dent Res 2005: 84:741–746.

209. Mazzoni A, Carrilho M, Papa V, Tjäderhane L, GobbiP, Nucci C, Di Lenarda R, Mazzotti G, Tay FR,Pashley DH, Breschi L. MMP-2 assay within thehybrid layer created by a two-step etch-and-rinse adhe-sive: biochemical and immunohistochemical analysis.J Dent 2011: 39: 470–477.

210. Nishitani Y, Yoshiyama M, Wadgaonkar B, Breschi L,Mannello F, Mazzoni A, Carvalho RM, Tjäderhane L,

Carvalho et al.

84

Page 24: Dentina Como Sustrato

Tay FR, Pashley DH. Activation of gelatinolytic/collagenolytic activity in dentin by self-etching adhe-sives. Eur J Oral Sci 2006: 114: 160–166.

211. Tay FR, Pashley DH, Loushine RJ, Weller RN,Monticelli F, Osorio R. Self-etching adhesives increasecollagenolytic activity in radicular dentin. J Endod2006: 32: 862–868.

212. Breschi L, Mazzoni A, Ruggeri A, Cadenaro M, DiLenarda R, De Stefano Dorigo E. Dental adhesionreview: aging and stability of the bonded interface.Dent Mater 2008: 24: 90–101.

213. Gendron R, Grenier D, Sorsa T, Mayrand D. Inhibi-tion of the activities of matrix metalloproteinases 2, 8,and 9 by chlorhexidine. Clin Diagn Lab Immunol1999: 6: 437–439.

214. Carrilho MR, Tay FR, Donnelly AM, Agee KA,Tjäderhane L, Mazzoni A, Breschi L, Foulger S,Pashley DH. Host-derived loss of dentin matrixstiffness associated with solubilization of collagen.J Biomed Mater Res B Appl Biomater 2009: 90: 373–380.

215. Garcia MB, Carrilho MR, Nor JE, Anauate-Netto C,Anido-Anido A, Amore R, Tjäderhane L, Bretz WA.Chlorhexidine inhibits the proteolytic activity of rootand coronal carious dentin in vitro. Caries Res 2009:43: 92–96.

216. Zhou J, Tan J, Yang X, Xu X, Li D, Chen L. MMP-inhibitory effect of chlorhexidine applied in aself-etching adhesive. J Adhes Dent 2011: 13: 111–115.

217. Breschi L, Cammelli F, Visintini E, Mazzoni A, Vita F,Carrilho M, Cadenaro M, Foulger S, Mazzoti G, TayFR, Di Lenarda R, Pashley D. Influence of chlorhexi-dine concentration on the durability of etch-and-rinsedentin bonds: a 12-month in vitro study. J Adhes Dent2009: 11: 191–198.

218. Breschi L, Mazzoni A, Nato F, Carrilho M, Visintini E,Tjäderhane L, Ruggeri A Jr, Tay FR, Dorigo Ede S,Pashley DH. Chlorhexidine stabilizes the adhesiveinterface: a 2-year in vitro study. Dent Mater 2010:26: 320–325.

219. Campos EA, Correr GM, Leonardi DP, Barato-FilhoF, Gonzaga CC, Zielak JC. Chlorhexidine diminishesthe loss of bond strength over time under simulatedpulpal pressure and thermo-mechanical stressing.J Dent 2009: 37: 108–114.

220. Komori PC, Pashley DH, Tjäderhane L, Breschi L,Mazzoni A, de Goes MF, Wang L, Carrilho MR. Effectof 2% chlorhexidine digluconate on the bond strengthto normal versus caries-affected dentin. Oper Dent2009: 34: 157–165.

221. Stanislawczuk R, Reis A, Loguercio AD. A 2-yearin vitro evaluation of a chlorhexidine-containing acidon the durability of resin–dentin interfaces. J Dent2011: 39: 40–47.

222. Zhou J, Tan J, Chen L, Li D, Tan Y. The incorpora-tion of chlorhexidine in a two-step self-etching adhe-sive preserves dentin bond in vitro. J Dent 2009: 37:807–812.

223. Tezvergil-Mutluay A, Tjäderhane L. Current conceptsin dental adhesion. Tandlaegebladet 2011: 115:36–42.

224. Pashley DH, Tay FR, Imazato S. How to increasethe durability of resin–dentin bonds. Compend ContinEduc Dent 2011: 32: 60–64.

225. Zhang SC, Kern M. The role of host-derived dentinalmatrix metalloproteinases in reducing dentin bondingof resin adhesives. Int J Oral Sci 2009: 1: 163–176.

226. Hosaka K, Nishitani Y, Tagami J, Yoshiyama M, Brack-ett WW, Agee KA, Tay FR, Pashley DH. Durability ofresin–dentin bonds to water- vs. ethanol-saturateddentin. J Dent Res 2009: 88: 146–151.

227. Sadek FT, Braga RR, Muench A, Liu Y, Pashley DH,Tay FR. Ethanol wet-bonding challenges currentanti-degradation strategy. J Dent Res 2010: 89: 1499–1504.

228. Tay FR, Gutmann JL, Pashley DH. Microporous,demineralized collagen matrices in intact radiculardentin created by commonly used calcium-depletingendodontic irrigants. J Endod 2007: 33: 1086–1090.

229. Tezvergil-Mutluay A, Agee KA, Uchiyama T, ImazatoS, Mutluay MM, Cadenaro M, Breschi L, Nishitani Y,Tay FR, Pashley DH. The inhibitory effects of quater-nary ammonium methacrylates on soluble and matrix-bound MMPs. J Dent Res 2011: 90: 535–540.

230. Breschi L, Martin P, Mazzoni A, Nato F, Carrilho M,Tjäderhane L, Visintini E, Cadenaro M, Tay FR, DeStefano Dorigo E, Pashley DH. Use of a specificMMP-inhibitor (galardin) for preservation of hybridlayer. Dent Mater 2010: 26: 571–578.

231. Al-Ammar A, Drummond JL, Bedran-Russo AK. Theuse of collagen cross-linking agents to enhance dentinbond strength. J Biomed Mater Res B Appl Biomater2009: 91: 419–424.

232. Bedran-Russo AK, Vidal CM, Dos Santos PH, Castel-lan CS. Long-term effect of carbodiimide on dentinmatrix and resin–dentin bonds. J Biomed Mater Res BAppl Biomater 2010: 94: 250–255.

233. Castellan CS, Pereira PN, Grande RH, Bedran-RussoAK. Mechanical characterization of proanthocyanidin–dentin matrix interaction. Dent Mater 2010: 26: 968–973.

234. Cova A, Breschi L, Nato F, Ruggeri A Jr, Carrilho M,Tjäderhane L, Prati C, Di Lenarda R, Tay FR, PashleyDH, Mazzoni A. Effect of UVA-activated riboflavin ondentin bonding. J Dent Res 2011: 90: 1439–1445.

235. Kim YK, Grandini S, Ames JM, Gu LS, Kim SK,Pashley DH, Gutmann JL, Tay FR. Critical review onmethacrylate resin-based root canal sealers. J Endod2010: 36: 383–399.

236. Mai S, Kim YK, Kim J, Yiu CK, Ling J, Pashley DH,Tay FR. In vitro remineralization of severely compro-mised bonded dentin. J Dent Res 2010: 89: 405–410.

237. Tay FR, Pashley DH. Biomimetic remineralization ofresin-bonded acid-etched dentin. J Dent Res 2009: 88:719–724.

238. Kim YK, Mai S, Mazzoni A, Liu Y, Tezvergil-MutluayA, Takahashi K, Zhang K, Pashley DH, Tay FR.

Dentin bonding

85

Page 25: Dentina Como Sustrato

Biomimetic remineralization as a progressive dehydra-tion mechanism of collagen matrices—implications inthe aging of resin–dentin bonds. Acta Biomater 2010:6: 3729–3739.

239. Salehrabi R, Rotstein I. Endodontic treatment out-comes in a large patient population in the USA: anepidemiological study. J Endod 2004: 30: 846–850.

240. Tilashalski KR, Gilbert GH, Boykin MJ, Shelton BJ.Root canal treatment in a population-based adultsample: status of teeth after endodontic treatment.J Endod 2004: 30: 577–581.

241. Imazato S, Kuramoto A, Takahashi Y, Ebisu S, PetersMC. In vitro antibacterial effects of the dentin primer ofClearfil Protect Bond. Dent Mater 2006: 22: 527–532.

242. Kijsamanmith K, Timpawat S, Harnirattisai C, MesserHH. Micro-tensile bond strengths of bonding agentsto pulpal floor dentine. Int Endod J 2002: 35: 833–839.

243. Nanci A. Ten Cate’s Oral Histology: Development,Structure, and Function, 7th edn. St. Louis: Elsevier,2007.

244. Carrigan PJ, Morse DR, Furst ML, Sinai IH. A scan-ning electron microscopic evaluation of human den-tinal tubules according to age and location. J Endod1984: 10: 359–363.

245. Ferrari M, Mannocci F, Vichi A, Cagidiaco MC, MjörIA. Bonding to root canal: structural characteristics ofthe substrate. Am J Dent 2000: 13: 255–260.

246. Bouillaguet S, Troesch S, Wataha JC, Krejci I, MeyerJM, Pashley DH. Microtensile bond strength betweenadhesive cements and root canal dentin. Dent Mater2003: 19: 199–205.

247. Paqué F, Laib A, Gautschi H, Zehnder M. Hard-tissuedebris accumulation analysis by high-resolution com-puted tomography scans. J Endod 2009: 35: 1044–1047.

248. Williamson AE, Sandor AJ, Justman BC. A comparisonof three nickel–titanium rotary systems, Endo-Sequence, ProTaper universal, and profile GT, forcanal-cleaning ability. J Endod 2009: 35: 107–109.

249. Carvalho RM, Pereira JC, Yoshiyama M, Pashley DH.A review of polymerization contraction: the influenceof stress development versus stress relief. Oper Dent1996: 21: 17–24.

250. Tay FR, Loushine RJ, Lambrechts P, Weller RN,Pashley DH. Geometric factors affecting dentinbonding in root canals: a theoretical modelingapproach. J Endod 2005: 31: 584–589.

251. Caiado AC, de Goes MF, de Souza-Filho FJ, Ruegge-berg FA. The effect of acid etchant type and dentinlocation on tubular density and dimension. J ProsthetDent 2010: 103: 352–361.

252. Faria e Silva AL, Casselli DS, Ambrosano GM, MartinsLR. Effect of the adhesive application mode and fiberpost translucency on the push-out bond strength todentin. J Endod 2007: 33: 1078–1081.

253. Perdigao J, Geraldeli S, Lee IK. Push-out bondstrengths of tooth-colored posts bonded with differentadhesive systems. Am J Dent 2004: 17: 422–426.

254. Perdigao J, Lopes MM, Gomes G. Interfacial adapta-tion of adhesive materials to root canal dentin. J Endod2007: 33: 259–263.

255. Bell AM, Lassila LV, Kangasniemi I, Vallittu PK.Bonding of fibre-reinforced composite post to rootcanal dentin. J Dent 2005: 33: 533–539.

256. Goracci C, Tavares AU, Fabianelli A, Monticelli F,Raffaelli O, Cardoso PC, Tay F, Ferrari M. The adhe-sion between fiber posts and root canal walls: compari-son between microtensile and push-out bond strengthmeasurements. Eur J Oral Sci 2004: 112: 353–361.

257. Ishioka S, Caputo AA. Interaction between the den-tinal smear layer and composite bond strength. JProsthet Dent 1989: 61: 180–185.

258. Gwinnett AJ. Quantitative contribution of resininfiltration/hybridization to dentin bonding. Am JDent 1993: 6: 7–9.

259. Meryon SD, Tobias RS, Jakeman KJ. Smear removalagents: a quantitative study in vivo and in vitro.J Prosthet Dent 1987: 57: 174–179.

260. Perdigao J, Duarte S Jr, Lopes MM. Advances indentin adhesion. Compend Contin Educ Dent 2003:24(Suppl): 10–16; quiz 61.

261. Christensen GJ. Preventing postoperative tooth sensi-tivity in class I, II and V restorations. J Am Dent Assoc2002: 133: 229–231.

262. Opdam NJ, Roeters FJ, Feilzer AJ, Verdonschot EH.Marginal integrity and postoperative sensitivity in Class2 resin composite restorations in vivo. J Dent 1998:26: 555–562.

263. Schwartz RS. Adhesive dentistry and endodontics.Part 2: bonding in the root canal system—the promiseand the problems: a review. J Endod 2006: 32: 1125–1134.

264. Schwartz RS, Fransman R. Adhesive dentistry andendodontics: materials, clinical strategies and proce-dures for restoration of access cavities: a review.J Endod 2005: 31: 151–165.

265. Torabinejad M, Handysides R, Khademi AA, BaklandLK. Clinical implications of the smear layer in endo-dontics: a review. Oral Surg Oral Med Oral PatholOral Radiol Endod 2002: 94: 658–666.

266. Goracci C, Sadek FT, Fabianelli A, Tay FR, Ferrari M.Evaluation of the adhesion of fiber posts to intra-radicular dentin. Oper Dent 2005: 30: 627–635.

267. White RR, Goldman M, Lin PS. The influence ofthe smeared layer upon dentinal tubule penetrationby plastic filling materials. J Endod 1984: 10: 558–562.

268. Kim YK, Mai S, Haycock JR, Kim SK, Loushine RJ,Pashley DH, Tay FR. The self-etching potential ofRealSeal versus RealSeal SE. J Endod 2009: 35: 1264–1269.

269. Mai S, Kim YK, Hiraishi N, Ling J, Pashley DH, TayFR. Evaluation of the true self-etching potential of afourth generation self-adhesive methacrylate resin-based sealer. J Endod 2009: 35: 870–874.

270. Cantoro A, Goracci C, Carvalho CA, Coniglio I,Ferrari M. Bonding potential of self-adhesive luting

Carvalho et al.

86

Page 26: Dentina Como Sustrato

agents used at different temperatures to lute compositeonlays. J Dent 2009: 37: 454–461.

271. De Munck J, Vargas M, Van Landuyt K, Hikita K,Lambrechts P, Van Meerbeek B. Bonding of an auto-adhesive luting material to enamel and dentin. DentMater 2004: 20: 963–971.

272. Monticelli F, Osorio R, Mazzitelli C, Ferrari M,Toledano M. Limited decalcification/diffusion of self-adhesive cements into dentin. J Dent Res 2008: 87:974–979.

273. Boone KJ, Murchison DF, Schindler WG, Walker WA3rd. Post retention: the effect of sequence of post-space preparation, cementation time, and differentsealers. J Endod 2001: 27: 768–771.

274. Breschi L, Mazzoni A, Stefano Dorigo E, Ferrari M.Adhesion to intraradicular dentin: a review. J Adhes SciTech 2009: 23: 1053–1083.

275. Standlee JP, Caputo AA. Endodontic dowel retentionwith resinous cements. J Prosthet Dent 1992: 68: 913–917.

276. Serafino C, Gallina G, Cumbo E, Ferrari M. Surfacedebris of canal walls after post space preparation inendodontically treated teeth: a scanning electronmicroscopic study. Oral Surg Oral Med Oral PatholOral Radiol Endod 2004: 97: 381–387.

277. Prado M, Gusman H, Gomes BP, Simao RA. Scanningelectron microscopic investigation of the effectivenessof phosphoric acid in smear layer removal when com-pared with EDTA and citric acid. J Endod 2011: 37:255–258.

278. Saleh AA, Ettman WM. Effect of endodontic irrigationsolutions on microhardness of root canal dentine.J Dent 1999: 27: 43–46.

279. Coniglio I, Magni E, Goracci C, Radovic I, CarvalhoCA, Grandini S, Ferrari M. Post space cleaning usinga new nickel–titanium endodontic drill combinedwith different cleaning regimens. J Endod 2008: 34:83–86.

280. Condon JR, Ferracane JL. Assessing the effect ofcomposite formulation on polymerization stress. J AmDent Assoc 2000: 131: 497–503.

281. Feilzer AJ, Dauvillier BS. Effect of TEGDMA/BisGMA ratio on stress development and viscoelasticproperties of experimental two-paste composites.J Dent Res 2003: 82: 824–828.

282. Sakaguchi RL, Wiltbank BD, Murchison CF. Predic-tion of composite elastic modulus and polymerizationshrinkage by computational micromechanics. DentMater 2004: 20: 397–401.

283. Bouillaguet S, Bertossa B, Krejci I, Wataha JC, Tay FR,Pashley DH. Alternative adhesive strategies to opti-mize bonding to radicular dentin. J Endod 2007: 33:1227–1230.

284. Fisher MA, Berzins DW, Bahcall JK. An in vitro com-parison of bond strength of various obturation mate-rials to root canal dentin using a push-out test design.J Endod 2007: 33: 856–858.

285. Gesi A, Raffaelli O, Goracci C, Pashley DH, TayFR, Ferrari M. Interfacial strength of Resilon and

gutta-percha to intraradicular dentin. J Endod 2005:31: 809–813.

286. Lawson MS, Loushine B, Mai S, Weller RN, PashleyDH, Tay FR, Loushine RJ. Resistance of a 4-META-containing, methacrylate-based sealer to dislocation inroot canals. J Endod 2008: 34: 833–837.

287. Santos J, Tjäderhane L, Ferraz C, Zaia A, Alves M, DeGoes M, Carrilho M. Long-term sealing ability ofresin-based root canal fillings. Int Endod J 2010: 43:455–460.

288. Ungor M, Onay EO, Orucoglu H. Push-out bondstrengths: the Epiphany-Resilon endodontic obtura-tion system compared with different pairings ofEpiphany, Resilon, AH Plus and gutta-percha. IntEndod J 2006: 39: 643–647.

289. Ureyen Kaya B, Keçeci AD, Orhan H, Belli S.Micropush-out bond strengths of gutta-percha versusthermoplastic synthetic polymer-based systems—an exvivo study. Int Endod J 2008: 41: 211–218.

290. Sly MM, Moore BK, Platt JA, Brown CE. Push-outbond strength of a new endodontic obturation system(Resilon/Epiphany). J Endod 2007: 33: 160–162.

291. Baumgartner G, Zehnder M, Paqué F. Enterococcusfaecalis type strain leakage through root canals filledwith gutta-percha/AH Plus or Resilon/Epiphany.J Endod 2007: 33: 45–47.

292. Munoz HR, Saravia-Lemus GA, Florian WE,Lainfiesta JF. Microbial leakage of Enterococcus faecalisafter post space preparation in teeth filled in vivowith RealSeal versus gutta-percha. J Endod 2007: 33:673–675.

293. Onay EO, Ungor M, Orucoglu H. An in vitro evalu-ation of the apical sealing ability of a new resin-basedroot canal obturation system. J Endod 2006: 32: 976–978.

294. Cheung W. A review of the management of endodon-tically treated teeth. Post, core and the final restora-tion. J Am Dent Assoc 2005: 136: 611–619.

295. Gordon MP. The removal of gutta-percha and rootcanal sealers from root canals. N Z Dent J 2005: 101:44–52.

296. Shahravan A, Haghdoost AA, Adl A, Rahimi H,Shadifar F. Effect of smear layer on sealing abilityof canal obturation: a systematic review and meta-analysis. J Endod 2007: 33: 96–105.

297. Kokkas AB, Boutsioukis A, Vassiliadis LP, StavrianosCK. The influence of the smear layer on dentinaltubule penetration depth by three different root canalsealers: an in vitro study. J Endod 2004: 30: 100–102.

298. Kouvas V, Liolios E, Vassiliadis L, Parissis-MessimerisS, Boutsioukis A. Influence of smear layer on depth ofpenetration of three endodontic sealers: an SEM study.Endod Dent Traumatol 1998: 14: 191–195.

299. Coniglio I, Carvalho CA, Magni E, Cantoro A, FerrariM. Post space debridement in oval-shaped canals: theuse of a new ultrasonic tip with oval section. J Endod2008: 34: 752–755.

300. Goldman LB, Goldman M, Kronman JH, Lin PS. Theefficacy of several irrigating solutions for endodontics:

Dentin bonding

87

Page 27: Dentina Como Sustrato

a scanning electron microscopic study. Oral Surg OralMed Oral Pathol 1981: 52: 197–204.

301. Takeda FH, Harashima T, Kimura Y, Matsumoto K. Acomparative study of the removal of smear layer bythree endodontic irrigants and two types of laser. IntEndod J 1999: 32: 32–39.

302. Mjör IA, Smith MR, Ferrari M, Mannocci F. Thestructure of dentine in the apical region of humanteeth. Int Endod J 2001: 34: 346–353.

303. Cury AH, Goracci C, de Lima Navarro MF, CarvalhoRM, Sadek FT, Tay FR, Ferrari M. Effect of hygro-scopic expansion on the push-out resistance of glass

ionomer-based cements used for the luting of glassfiber posts. J Endod 2006: 32: 537–540.

304. Goldman M, DeVitre R, White R, Nathanson D. AnSEM study of posts cemented with an unfilled resin.J Dent Res 1984: 63: 1003–1005.

305. Schmage P, Sohn J, Nergiz I, Ozcan M. Variousconditioning methods for root canals influencing thetensile strength of titanium posts. J Oral Rehabil 2004:31: 890–894.

306. Schmage P, Sohn J, Ozcan M, Nergiz I. Effect ofsurface treatment of titanium posts on the tensile bondstrength. Dent Mater 2006: 22: 189–194.

Carvalho et al.

88

Page 28: Dentina Como Sustrato

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