RESEARCH AND EDUCATION

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616

Adjusting dental ceramics: An in vitro evaluation of the abilityof various ceramic polishing kits to mimic glazed dental

ceramic surface

René Steiner, DMD,a Ulrike S. Beier, DMD, MSc,b Irene Heiss-Kisielewsky, DMD,c Robert Engelmeier, DMD, MS,d

Herbert Dumfahrt, DMD,e and Matilda Dhima, DMD, MSf

ABSTRACTStatement of problem. During the insertion appointment, the practitioner is often faced with theneed to adjust ceramic surfaces to fit a restoration to the adjacent or opposing dentition and softtissues.

Purpose. The purpose of this study was to assess the ceramic surface smoothness achieved withvarious commercially available ceramic polishing kits on different commonly used ceramic systems.The reliability of the cost of a polishing kit as an indicator of improved surface smoothness wasassessed.

Material and methods. A total of 350 ceramic surfaces representing 5 commonly available ceramicsystems (IPS Empress Esthetic, IPS e.max Press, Cergo Kiss, Vita PM 9, Imagine PressX) were treatedwith 5 types of ceramic polishing systems (Cerapreshine, 94006C, Ceramiste, Optrafine, Zenostar) byfollowing the manufacturers’ guidelines. The surface roughness was measured with a profilometer(Taylor Hobson; Precision Taylor Hobson Ltd). The effects of ceramic systems and polishing kits ofinterest on surface roughness were analyzed by 2-way ANOVA, paired t test, and Bonferronicorrected significance level.

Results. The ceramic systems and polishing kits statistically affected surface roughness (P<.001).Thepolishing kit Zenostar on IPS e.max Press created the smoothest ceramic surface. No correlationcould be established between the high cost of the polishing kit and low surface roughness. None ofthe commonly used ceramic polishing kits could create a surface smoother than that of glazedceramic (P<.001).

Conclusions. The inclusion of a diamond polishing paste step is recommended to improve surfacesmoothness (P<.001). The cost of ceramic polishing kits is not recommended as a reliable indicatorof better performance of ceramic polishing kits (P>.30). (J Prosthet Dent 2015;113:616-622)

Clinically, chairside adjust-ments of ceramic restorationsinvolve roughening of theceramic surface by diamondrotary instruments and subse-quent polishing to restoresurface smoothness. The re-sulting surface roughness hasbeen shown to decrease flex-ural strength, which maycompromise the long-termprognosis of the restoration.1

Several studies have shownthat rough ceramic surfacesas a result of insufficient pol-ishing lead to an increasedadhesion of bacteria and thatrough surfaces are insuffi-ciently cleanable by patients.2-6

The disadvantages of poorlypolished surfaces are notrestricted to the restoration.Rough surfaces may havean abrasive effect on antago-

nistic and adjacent teeth. Studies using a masticationsimulator have shown that increasing ceramic surfaceroughness causes significant wear on the antagonistictooth.7,8

ofessor, Department of Restorative Sciences, Innsbruck Medical Universityofessor, Department of Restorative Sciences, Innsbruck Medical Universityofessor, Department of Restorative Sciences, Innsbruck Medical Universityd Chair, Department of Prosthodontics, University of Pittsburgh School ofnsbruck Medical University, Innsbruck, Austria.fessor, Department of Prosthodontics, University of Pittsburgh School of D

Polishing ceramic restorations may be done by us-ing polishing kits, disks, or cleaning-prophylaxis pastematerials. Surface smoothness has been shown toimprove more effectively with polishing kits and disks

, Innsbruck, Austria., Innsbruck, Austria., Innsbruck, Austria.Dental Medicine, Pittsburgh, Pa.

ental Medicine, Pittsburgh, Pa.

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Figure 1. Representative specimen showing treatment of surface spec-imen with 4 different treatments before polishing with various polishingkits and glaze.

P1P2

C1

C2

C31 ceramic samplewith 2 surfaces

5 ceramic systems 5 ceramic polishing kits

x 14

= 1

75 c

eram

ic s

ampl

es w

ith

350

surf

aces

C4

C5

P3P4P5

P1P2P3P4P5

P1P2P3P4P5

P1P2P3P4P5

P1P2P3P4P5

Figure 2. Description of how 350 specimens were prepared, treated, andtested.

Clinical ImplicationsPractitioners must select a chairside ceramic pol-ishing kit that ensures surface smoothness,efficiency in time and cost, and successful long-termrestoration outcome.

June 2015 617

compared to polishing pastes alone or in combinationwith disks.9 In addition to the mechanical polishing ofceramics to improve surface smoothness, the applica-tion of glaze is another consideration. One studycompared the surface smoothness of various ceramicsystems treated with glaze, pastes, rubber, disks, andabrasive paper, and concluded that clinically acceptablesurface smoothness could be obtained from glazingand paste approaches.10

Several studies have posed the question of whetherceramic polishing kits may help recreate a ceramic surfacesimilar to the originally glazed ceramic surface before anymodifications are made.11-15 A review of commerciallyavailable ceramic polishing kits showed a wide range ofcosts, techniques for use, and application steps. The costsof kits varied significantly (up to 90%). The recom-mended techniques and steps for use varied from pre-polishing with pumice paste to the use of flexible disksand diamond polishing paste steps with nylon brushes.

The aims of this study were to evaluate the ceramicsurface smoothness achieved with various commerciallyavailable ceramic polishing kits on different commonlyused ceramic systems in the dental practice and toevaluate the cost benefit ratio of the various ceramicpolishing kits. There were 2 null hypotheses: no statis-tically significant difference would be found in theceramic surface smoothness of various commerciallyavailable ceramic polishing kits, and a higher-costceramic polishing kit would not be associated with alower surface roughness of ceramic.

MATERIAL AND METHODS

A total of 350 ceramic specimens were fabricated from 4commonly used ceramic systems (Figs. 1, 2; Table 1). Thespecimens were fabricated according to the manufac-turer’s guidelines. Each specimen was waxed as a flat,square specimen (14×14 mm) of 2 mm in thickness. Adigital caliper (Digimatic IP67; Mitutoyo GmbH) wasused to ensure consistency in the dimensions of thespecimens waxed. The specimens in wax were invested ina phosphate-bonded investment material (IPS PressVest;Ivoclar Vivadent AG). Prefabricated ingots were pressedto ceramic specimens of the above dimensions with thelost-wax technique.

The pressing process was carried out in a press furnace(Programat EP 5000; Ivoclar Vivadent AG) according to

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the manufacturer’s instructions. Before the polishingprocess, specimens were inspected with an incident lightmicroscope (BX51M KK; Olympus Corp) at ×20 magni-fication to exclude surface irregularities. The defectivespecimens were characterized by the presence of blowholes caused by the pressing process. The defectivespecimens were removed and replaced with newspecimens.

Because each ceramic specimen has 2 surfaces, 350surfaces had to be polished and evaluated for surfaceroughness (a total of 175 specimens with 2 surfaces, fora total of 350 surfaces). The glazed ceramic surfaceserved as control. Each area was prepared as follows torepresent various chairside methods of adjusting aceramic restoration. Initially, for more bulk removalof the ceramic, diamond rotary instruments were used.

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Table 1. Ceramic systems evaluated

Ceramic System Manufacturer

IPS Empress Esthetic Ivoclar Vivadent AG

IPS e.max Press Ivoclar Vivadent AG

Cergo Kiss DeguDent a Dentsply Co

Vita PM 9 Vita Zahnfabrik H. Rauter GmbH & Co KG

Imagine PressX Wieland Dental+Technik GmbH & Co KG

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After adjustment with a diamond rotary instrument hadbeen completed, a polishing kit was used to improvethe surface smoothness of the area adjusted. Area 1 wasglazed by applying the specific glaze medium for eachceramic and was left intact as a control. Areas 2, 3, and4 were roughened with a red-striped diamond rotaryfinishing instrument (grit 30 mm) [ISO 806 314 158 514014] (Komet; Komet Group). Areas 3 and 4 were thenprepared with a yellow-striped diamond rotary finishinginstrument (grit 15 mm) [ISO 806 314 158 504 014](Komet; Komet Group). Area 4 was also polished withvarious ceramic polishing kits. The specimens werepolished for 30 seconds in one direction and for another30 seconds at 90 degrees to the first direction. Simu-lating a clinical scenario, a contraangle rotary instru-ment with a 1:1 transmission was used (956 LX; W&HGmbH). Each polishing process was completed in arunning direction under water cooling (50 mL/min) atthe recommended speed range and was carried out by asingle investigator (RS). The prepared specimens werecleaned with 95% alcohol, dried, and prepared forroughness measurement.

Five polishing kits were evaluated for each ceramicsystem (Figs. 1, 2). In an effort to clearly distinguish eachceramic polishing kit, differentiating between 2- and 3-step polishing kits was necessary. Because the IvoclarVivadent polishing kit provides an additional polishingstep with a diamond polishing paste and nylon brushes,the corresponding ceramic specimens were polished

Table 2. Technical characteristics of different polishing kits

ManufacturerPolishing Kit

Name ISO/REF No.PolishingSteps

Length(mm)

DiatechColtène/Whaledent AG

CerapreshineCerashine

ISO 658 204243 524 110

2 10

Komet Gebr.Brassler GmbH &Co

94006 C, 94006 M,94006 F

REF 94006 C,M, F, 204 050

3 10.5

ShofuHigashiyama-ku

CeramistéStandard UltraUltra II

ISO 652 206252 515 040525 565

3 14.5

Ivoclar Vivadent OptraFine REF 601 989 ANdiamond polishing paste

2+D-p-p 7.5

WielandDental+TechnikGmbH

Zenostar PrepolishFinish Glossy

REF 6901 999023 025 026

3 11, 7.5

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again for 60 seconds without water cooling as recom-mended by the manufacturers. Table 1 provides anoverview of each ceramic polishing kit.

On the basis of preinvestigation statistical assess-ment, each polishing process was repeated 14 times. Inthis process, a new polisher completed the polishingsteps after 7 polishing procedures. Both polishers werecalibrated to ensure consistency in polishing andinspection.

The surface roughness was measured with a profil-ometer (Taylor Hobson Precision Talysurf Series 2; TaylorHobson Ltd). The values of interest were Ra (arithmeticroughness mean), Rz (averaged roughness depth), and Rt

(roughness depth) according to ISO 4287.16 Because theRt value is very sensitive to outliers, it was consulted onlylast in the analysis. The focus was set on the Rz value,which by definition “considers an outlier just for 20%.”17

Each measurement was made at a right angle to thelast polishing direction. The values were diagrammedand tabulated. The surface roughness was further eval-uated with scanning electron microscopy. The associatedcosts of each polishing kit were recorded and analyzed onthe basis of performance.

A 2-way ANOVA was used to analyze differenceswithin repeated measurements for the 2 parameters ofinterest (ceramic system and polishing kit) (a=.05). Thiswas followed by paired t tests for multiple comparisons.The Bonferroni method was used to correct pairwisecomparisons (a=.001). All statistical analyses werecompleted with software (SPSS v20.0; IBM Corp).

RESULTS

The technical characteristics of the different polishing kitsand associated costs are shown in Table 2 and surfaceroughness values in Table 3. The polishing kits haveeither 2 or 3 steps of treatment but vary in instrumentdimensions, recommended speeds, and costs. The

Diameter(mm)

Max.Circumference

(mm)Recommended

Speed Range (rpm)

MeanRunningSpeed

(mm/sec)

PriceSegment($/piece)

5 15.7 5000-10 000max. 20 000

1309-2618 <2.50

5 15.7 Opt. 6000max. 15 000

1570-3925 >8.74

4 12.6 10 000-12 000max. 20 000

2100-2520 <2.50

3 9.4 10 000-max. 15 000;7000-max. 10 000

1567-2350 w4.99

5, 3 5.7, 9.4 6000-15 000 1570-3925,940-2350

>8.74

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Table 3. Roughness values (Ra, mm) for ceramic systems after various surface treatments compared to glazed surface

CeramicSystem

Polishing System

Glaze Diatech Komet Shofu WielandIvoclar

Vivadent

DiamondPolishing

Paste IvoclarVivadent

Red DiamondRotary

Instrument

YellowDiamondRotary

Instrument

IPS EmpressEsthetic

0.0309 ±0.01 0.1899 ±0.036 0.3301 ±0.054 0.1080 ±0.029 0.2288 ±0.047 0.3582 ±0.078 0.0913 ±0.019 1.1504 ±0.1003 0.5097 ±0.0604

IPS e.maxPress

0.0274 ±0.008 0.1958 ±0.037 0.1971 ±0.06 0.1072 ±0.029 0.0969 ±0.038 0.2363 ±0.0401 0.0294 ±0.006 0.7487 ±0.088 0.2434 ±0.04

Cergo Kiss 0.0219 ±0.003 0.1849 ±0.023 0.3159 ±0.054 0.1289 ±0.022 0.2833 ±0.051 0.3803 ±0.071 0.0651 ±0.022 1.1832 ±0.095 0.5435 ±0.059

Vita PM 9 0.0471 ±0.011 0.1740 ±0.024 0.3768 ±0.045 0.1251 ±0.029 0.3832 ±0.1004 0.4769 ±0.07 0.1042 ±0.039 1.2269 ±0.06 0.6146 ±0.054

ImaginePressX

0.0256 ±0.006 0.1833 ±0.038 0.3410 ±0.052 0.1141 ±0.018 0.2762 ±0.052 0.4015 ±0.059 0.1094 ±0.037 1.1650 ±0.084 0.5568 ±0.049

Ra, arithmetic roughness mean.

Table 4. Two-way ANOVA showing sources of variability

Source VariabilityType III Sumof Squares df Mean Square F

Ceramic system (P<.001) Sphericity assumed 2.467 4 0.617 207.132

Greenhouse-Geisser 2.467 3.240 0.762 207.132

Huynh-Feldt 2.467 4.000 0.617 207.132

Lower bound 2.467 1.000 2.467 207.132

Error(Ceramic system) Sphericity assumed 0.155 52 0.003

Greenhouse-Geisser 0.155 42.117 0.004

Huynh-Feldt 0.155 52.000 0.003

Lower bound 0.155 13.000 0.012

Polishing kit (P<.001) Sphericity assumed 53.882 7 7.697 2263.493

Greenhouse-Geisser 53.882 3.233 16.666 2263.493

Huynh-Feldt 53.882 4.430 12.164 2263.493

Lower bound 53.882 1.000 53.882 2263.493

Error(Polishing kit) Sphericity assumed 0.309 91 0.003

Greenhouse-Geisser 0.309 42.030 0.007

Huynh-Feldt 0.309 57.585 0.005

Lower bound 0.309 13.000 0.024

Ceramic system×Polishing kit (P<.001) Sphericity assumed 2.162 28 0.077 28.862

Greenhouse-Geisser 2.162 6.777 0.319 28.862

Huynh-Feldt 2.162 14.926 0.145 28.862

Lower bound 2.162 1.000 2.162 28.862

Error(Ceramic system×Polishing kit) Sphericity assumed 0.974 364 0.003

Greenhouse-Geisser 0.974 88.105 0.011

Huynh-Feldt 0.974 194.044 0.005

Lower bound 0.974 13.000 0.075

Significance, P<.001.

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parameters of interest, ceramic systems (P<.001) andceramic polishing kits (P<.001), showed a statisticallysignificant effect on surface roughness with a statisticallysignificant interaction between the 2 parameters of in-terest (P<.001) (Table 4).

Table 3 summarizes surface roughness values uponcompletion of the polishing treatment for each ceramicsystem and polishing kit. Overall, the red diamond rotaryinstrument resulted in the highest surface roughness andglazed surfaces, which were the control, showed thelowest surface roughness. The yellow marked diamondrotary finishing instrument (grit 15 mm) produced a

Steiner et al

significantly smoother surface on the IPS e.max Pressceramic system compared to the other ceramic systemstreated with the same rotary instrument (P<.001). Nostatistically significant difference was noted between thevarious ceramic systems in the control group treated withglaze only (P>.30).

None of the ceramic polishing kits was able to create asurface smoother than glaze (Table 3). The differences insurface roughness between glazed and polishedceramic areas were statistically significant (P<.001). TheCeramisté polishing kit (Shofu; Shofu Dental) producedthe lowest surface roughness on all ceramic systems,

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Figure 3. Scanning electron micrographs of dental ceramic surface afterfinishing (×1000 magnification). A, Glaze. B, Red diamond rotary instru-ment. C, Yellow diamond rotary instrument. D, Two-step polishing kit. E,Additional diamond paste polishing.

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except IPS e.max Press. The smoothest surface for IPSe.max Press ceramic systems was achieved with the Zen-ostar ceramic polishing kit (Wieland; Ivoclar Vivadent).

By adding another polishing step with diamond pol-ishing paste (Ivoclar Vivadent), the overall surfaceroughness was reduced statistically significantly (P<.001).With this additional polishing step, based on the Ra

value, IPS e.max Press surface smoothness was equiva-lent to the glazed IPS e.max Press ceramic surfacesmoothness (P>.50).

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The visual inspection of the polishers once polishingwas completed showed notable differences. Thisfinding was consistent with imaging obtained fromscanning electron microscopic imaging, as shown inFigure 3, where improvement in surface roughness wasnoted after the polishing of surfaces initially treatedwith diamond rotary instruments. Specifically, thepolishing kits of Diatech and Ivoclar Vivadent appearedto be consumed the most. In contrast, Shofu’s kitappeared nearly unchanged. No correlation could be

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0.0

Gla

ze

Dia

tech

Kom

et

Shof

u

Wie

land

Ivoc

lar V

ivad

ent

Dia

mon

d po

lishi

ngpa

ste

Ivoc

lar V

ivad

ent

Red

Dia

mon

dbu

r 30

µm

Yello

w D

iam

ond

bur 1

5 µm

0.2

0.4

0.6

R a-Va

lues

(µm

)

0.8

1.0

1.2

Polishing kit

Figure 4. Performance summary of polishing kits indicating better per-formance of glazed treatment. Addition of diamond polishing pastedecreased surface roughness similar to glazed treatment.

0<2.50 <2.50 ~4.99

Segment price ($)/piece>8.74 >8.74

0.05

0.1

0.15

0.2

R a-va

lues

(µm

)

0.25

0.3

0.35

Figure 5. Summary of cost and performance characteristics for variouspolishing kits evaluated. More expensive polishing kits did not showlower surface roughness compared to cheaper polishing kits.

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established between the wear of the polisher andpolishing efficiency (P>.30). The addition of diamondpolishing paste shows decreased surface roughnesssimilar to glazed treatment as noted in Figure 4. Anassessment of the cost versus performance of polishingkits (Fig. 5) shows that the more expensive polishingkits did not result in significantly smoother ceramicsurfaces (P>.30).

DISCUSSION

This study’s findings show that a statistically significantdifference in surface smoothness of ceramic systems re-sults from various commercially available ceramic pol-ishing kits (P<.001). The first null hypothesis wasrejected. The addition of a polishing step with diamondpaste recommended for one of the polishing kits(OptraFine; Ivoclar Vivadent) showed a significantimprovement in surface smoothness for all specimensregardless of the ceramic system. The addition of an extrapolishing step involves additional time spent chairsideand additional costs for materials. Furthermore, with thisextra polishing step, surface smoothness comparable tothe original glazed surface was possible. Clinically, thismay translate to the improved long-term performance ofthe restoration and possibly less bacterial adhesion andbetter soft tissue response.

A limitation to this study is how representative of apractitioner’s preferences are the ceramic polishing kitsand systems evaluated here. Of further interest is toassess these preferences and evaluate the systems clini-cally. In addition, although manufacturer guidelines areavailable, it is difficult to polish consistently with thesame pressure, speed and cycles.

A standardized procedure is essential to obtaincomparable and consistent polishing treatment among

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providers. In this study, we focused on standardizing thespecimen fabrication and calibrating the polishers. Thespecimen size was consistent with other studies evalu-ating ceramic systems.9,11-13,18-20

The comparison of findings with other studies is oftenchallenged by differences in specimen fabrication, surfaceroughness values analyzed and studied, and testingmethods. Apart from the measured data, the in-vestigators noted that the polishing kits of Diatech andShofu had less vibration than the Wieland and Kometpolishers.

Even though glaze application showed the best sur-face smoothness, the longevity of glaze is not wellestablished when restorations are in function. The Dia-tech polishing kit was the least expensive polishing sys-tem in this test series. Similar to the Diatech polishing kit,Shofu’s polishing kit was among the least expensive. Bothof these systems resulted in the lowest roughness values.The second null hypothesis was rejected. An advantage ofthe Shofu polishing kit is its lower wear, which allows forthis kit to be used on more than one restoration.

CONCLUSIONS

On the basis of the findings of this study, the followingconclusions were drawn. None of the commerciallyavailable ceramic polishing kits could create an initiallysmoother surface that glazed ceramic (P<.001). Theaddition of a polishing step with diamond polishing pasteis recommended to achieve a significant (P<.001)improvement in ceramic surface smoothness. The cost ofcommercially available ceramic polishing kits should notbe considered as an indicator of performance.

REFERENCES

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2. Anami LC, PereiraCA,Guerra E. Assunção e Souza RO, JorgeAO, BottinoMA.Morphology and bacterial colonisation of tooth/ceramic restoration interfaceafter different cement excess removal techniques. J Dent 2012;40:742-9.

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3. Aykent F, Yondem I, Ozyesil AG, Gunal SK, Avunduk MC, Ozkan S. Effect ofdifferent finishing techniques for restorative materials on surface roughnessand bacterial adhesion. J Prosthet Dent 2010;103:221-7.

4. Brentel AS, Kantorski KZ, Valandro LF, Fúcio SB, Puppin-Rontani RM,Bottino MA. Confocal laser microscopic analysis of biofilm on newer feldsparceramic. Oper Dent 2011;36:43-51.

5. Haralur SB. Evaluation of efficiency of manual polishing over autoglazed andoverglazed porcelain and its effect on plaque accumulation. J Adv Prostho-dont 2012;4:179-86.

6. Caesar H, Ernst S. Grundwissen für Zahntechniker, die Nichtmetalle.Munich: Neuer Merkur Verlag; 2007. p. 255.

7. Ghazal M, Kern M. The influence of antagonistic surface roughness on thewear of human enamel and nanofilled composite resin artificial teeth.J Prosthet Dent 2009;101:342-9.

8. Preis V, Weiser F, Handel G, Rosentritt M. Wear performance of monolithicdental ceramics with different surface treatments. Quintessence Int 2013;44:393-405.

9. Sarikaya I, Guler AU. Effects of different polishing techniques on the surfaceroughness of dental porcelains. J Appl Oral Sci 2010;18:10-6.

10. Yilmaz K, Ozkan P. Profilometer evaluation of the effect of various polishingmethods on the surface roughness in dental ceramics of different structuressubjected to repeated firings. Quintessence Int 2010;41:e125-31.

11. Boaventura JM, Nishida R, Elossais AA, Lima DM, Reis JM, Campos EA, et al.Effect finishing and polishing procedures on the surface roughness of IPSEmpress 2 ceramic. Acta Odontol Scand 2013;71:438-43.

12. Bottino MC, Valandro LF, Kantorski KZ, Bressiani JC, Bottino MA. Polishingmethods of an alumina-reinforced feldspar ceramic. Braz Dent J 2006;17:285-9.

13. Camacho GB, Vinha D, Panzeri H, Nonaka T, Goncalves M. Surfaceroughness of a dental ceramic after polishing with different vehicles anddiamond pastes. Braz Dent J 2006;17:191-4.

14. Flury S, Lussi A, Zimmerli B. Performance of different polishing techniquesfor direct CAD/CAM ceramic restorations. Oper Dent 2010;35:470-81.

Noteworthy Abstracts of

In vitro wear behavior of zirconia opposing e

Passos SP, Torrealba Y, Major P, Linke B, Flores-MJ Prosthodont 2014;24:593-601

Purpose. The aim of this systematic review was to assess enand to evaluate factors related to the wear of natural teeth o

Materials and Methods. Five electronic databases were sear“antagonist*,” “enamel,” “wear,” and “zirconi*” were used. Tfulfilled the inclusion criteria were selected for a full-text assesnot included.

Results. The database search strategy retrieved 142 potentialremoved, 62 studies were obtained. Titles and abstracts that fassessment (25). Seven laboratory studies met the inclusion cstudies were also screened.

Conclusions. There was a large variation in relation to weamovement, number and frequency of cycles, number of specenamel wear rates were lower against polished zirconia. Difcomparisons of wear rates among the studies.

Clinical Significance. Polishing the surface is recommendezirconia presents favorable wear behavior opposing natural t

Reprinted with permission of the American College of Prost

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15. Saraç D, Turk T, Elekdag-Turk S, Saraç YS. Comparison of 3 polishingtechniques for 2 all-ceramic materials. Int J Prosthodont 2007;20:465-8.

16. International Organization for Standardization. Geometrical product speci-fication (GPS) surface texture: profile method, terms, definitions and surfacetexture parameters. ISO 428. 1997. http://www.iso.ch/iso/en/prods-services/ISOstore/store.htm.

17. Sander M. Oberflächenmesstechnik für den Praktiker. Göttingen: FeinprüfPerthen 1993. p. 24.

18. Cury-Saramago Ade A, Coimbra PR, Izquierdo Ade M, Elias CN, Ruellas AC,et al. Ceramic surface polishing techniques after removal of orthodonticadhesive. Angle Orthod 2009;79:790-5.

19. Karan S, Toroglu MS. Porcelain refinishing with two different polishingsystems after orthodontic debonding. Angle Orthod 2008;78:947-53.

20. Tholt de Vasconcellos B, Miranda-Junior WG, Prioli R, Thompson J,Oda M. Surface roughness in ceramics with different finishing tech-niques using atomic force microscope and profilometer. Oper Dent2006;31:442-9.

Corresponding author:Dr René SteinerInnsbruck Medical UniversityClinical Department of Restorative and Prosthetic DentistryMZA, Anichstraße 35A-6020 InnsbruckAUSTRIAEmail: rene.steiner@uki.at

AcknowledgmentsThe authors thank Diatech (Coltène/Whaledent), Ivoclar Vivadent, Komet, Shofu,and Wieland for providing the ceramic polishing kits.

Copyright © 2015 by the Editorial Council for The Journal of Prosthetic Dentistry.

the Current Literature

namel: A systematic review

ir C, Nychka JA

amel wear on teeth opposing zirconia restorationspposing zirconia restorations.

ched through May 2013 without limitations. The termsitles and abstracts were initially screened, and those thatsment. Studies that evaluated only the material wear were

ly eligible studies. After the duplicate studies wereulfilled the inclusion criteria were selected for a full-textriteria. In addition, reference lists from the finally selected

r test method quantification, applied force, lateralimens, and enamel specimen preparation. In all studies,ferences in the test methods did not allow for

d for a full-contour zirconia restoration because polishedeeth.

hodontists.

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