Vertical ridge augmentation inthe esthetic zoneISABELLA ROCCHIETTA, LUCA FERRANTINO & MASSIMO SIMION

Bone remodeling after tooth extraction often leads toinadequate ridge dimensions for the ideal three-dimensional implant position (45). The lack of bonevolume, often associated with a scarcity of soft tis-sues, constitutes a major challenge for the clinician.This is especially true when dealing with esthetic sitesand, as such, managing severe defects in the anteriormaxillae is complex and often unpredictable. Thepresence of the nasal cavity limits the bone heightavailable for implant placement, and a large inter-arch space alters coronal length and form and pro-duces an unfavorable crown-to-root ratio in the finalprosthetic reconstruction. This can result in either anesthetically unacceptable final prosthetic restorationand/or in difficulties performing adequate oralhygiene, hence potentially jeopardizing the long-termprognosis (35). Bone augmentation (horizontal and/or vertical) using different techniques, based on dif-ferent biological principles, is often performed toovercome these deficiencies (12).

The first distractor reported in humans dates to1992, in which an extra-oral distractor was used inpatients with hemifacial microsomias (33). However,distraction osteogenesis may now be considered anobsolete therapy to augment bone because it is lim-ited to achieving bone regeneration in one vectoronly, often resulting in a lack of horizontal volumeand needing further regenerative procedures (2, 18).Autogenous block grafting has been advocated forthe correction of larger bone deficiencies (14, 78).Nonetheless, the increased morbidity of the recipientsite or long-term volumetric instability has encour-aged clinicians to utilize alternatives (13, 39). The useof titanium meshes has been shown to achieve three-dimensional alveolar ridge reconstruction (46, 47).However, its major drawback is the osseointegrationof the mesh itself, which makes it difficult to be

removed at the second phase of surgery. For mild andmoderate ridge defects, guided bone regenerationoffers the possibility of restoring the reabsorbed bonearchitecture through the application of particulatebone graft materials, in conjunction with barrier mem-branes, to stabilize and protect the graft materialsplaced (59).

The use of short or angled implants has also beenproposed in order to avoid major bone-augmentationprocedures in the posterior mandible and maxilla(41, 68). However, this is not normally contemplatedin the anterior maxillary region because of the highesthetic demands of this area. The advent of biomate-rials, in the treatment of alveolar defects, has createda paradigm shift in the therapeutic options available(60). The ease and reliability of three-dimensionalimaging and diagnostic tools has complemented theuse of tissue-engineering techniques to achieve boneregeneration in complex three-dimensional alveolardefects (19, 36). However, these novel techniquesrequire long-term data to assess predictability andstability.

The techniques mentioned above are frequentlyreported in the literature with regard to very specificparameters, such as implant-success/survival rates,marginal bone loss, complication rates, increasedbone volume and other site-specific data (48). Verylittle information is given regarding patient-centeredoutcomes. Bone-augmentation techniques, such asguided bone regeneration, are indicated in the ante-rior maxilla, which is considered an ‘esthetic area’.Hence, data on esthetic parameters and patient-dri-ven parameters would aid clinicians in the decision-making process. The aim of this narrative review is toassess patient-centered outcomes regarding verticalbone-augmentation procedures performed in theanterior maxilla.

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Printed in Singapore. All rights reserved PERIODONTOLOGY 2000

Guided bone regeneration

Guided bone regeneration is a procedure derivedfrom the principles of guided tissue regenerationaround natural teeth (42). The PASS principle (pri-mary wound closure, angiogenesis, space and stabil-ity of the clot) remains a cornerstone for successfulguided bone regeneration (80). Schenk et al. (52)demonstrated how newly regenerated bone pro-gresses, in a programmed sequence, through a seriesof biologic steps that closely mimic the pattern ofnormal bone growth and development. The princi-ples of guided bone regeneration were applied in theearly 1990s to atrophic jaws. Alveolar vertical defectswere treated using a titanium-reinforced, nonre-sorbable barrier membrane, in conjunction with tita-nium dental implants (62). The surgical techniquesand materials utilized have been developed since,aiming toward less invasive techniques with morepredictable outcomes. The expansion of indicationsfor guided bone regeneration to include a large vari-ety of bone defect types led to the widespread use ofthis technique in clinical practice. However, verticaldefects still represent the biggest challenge to thistechnique, especially in the anterior maxillae in whichthe aim is to achieve function and excellent estheticresults (29). The effectiveness of guided bone regener-ation with nonresorbable membranes, in obtainingvertical regeneration of the alveolar crest, has beenclinically and histologically documented in manystudies (44, 69). Moreover, the stability of bone verti-cally regenerated around dental implants and itsfavorable response under functional loading havebeen demonstrated in human subjects (1, 58). A sys-tematic review on clinical outcomes when usingguided bone regeneration for vertical bone augmen-tation, reported long-term stability (up to 7 years) ofthe augmented bone, confirming that vertically aug-mented bone responds to implant placement simi-larly to native, nonregenerated bone (48). This wasconfirmed by Urban et al. (73), who reported crestalremodeling of 1.01 � 0.57 mm at 12 months, whichremained stable throughout the 6-year follow-up per-iod after guided bone regeneration.

Vertical guided bone regeneration appears to behighly technique-sensitive and requires a long andcontrolled learning curve. A review reported failurerates ranging from 0% to 45% when using verticalguided bone regeneration (48), This was explained bythe variety of operators who performed the surgery,who may have adopted their own surgical techniquesand/or protocols. The main reasons for failure of

vertical guided bone regeneration are poor boneaugmentation as a result of soft-tissue dehiscenceand graft shrinkage because of poor blood supply.Granulation tissue formation and lack of adequatebone callus formation are generally caused by graftinstability, exposure of graft material to the oral envi-ronment and infection. Insufficient or delayed vascu-larization of the graft often leads to a mismatchbetween blood flow and bone resorption/formationcoupling, which can result in unpredictable boneaugmentation (79). The latter data derived fromstudies using nonresorbable expanded polytetrafluo-roethylene titanium-reinforced barrier membranes.Recently, new nonresorbable barrier membraneswere introduced with different pore sizes and struc-tural modifications. These have been speculated tobe more resistant to bacterial penetration, protectingthe regenerating bone and/or underlying implantswhilst achieving the same bone volume results(32, 49). However, thorough investigation and robuststudies are required to confirm the hypothesis.

Barrier membranes and grafts

The desired clinical outcome, as well as knowledge oflocal anatomy and biology of healing, drives thechoice of a specific membrane and graft. Guidedbone regeneration may be performed utilizing resorb-able or nonresorbable barriers, with or without graftmaterials. Recently, guided bone regeneration usingresorbable membranes has been shown to correct/augment ‘knife edge’ ridges (75). Nonetheless, whenintended to augment vertically, titanium-reinforceddense-polytetrafluoroethylene membranes may be abetter choice because of their ability to maintain/cre-ate space that is necessary for bone augmentation.Generally, when the alveolar defect may be self-con-tained (within the bony contours), the application ofa resorbable barrier membrane in combination witha particulate graft material allows for stabilization ofthe latter and hence bone regeneration (26). On thecontrary, when the alveolar defect presents extensivehorizontal and/or vertical bone deficiency, a space-maintaining approach is required to counteract theoverlying pressure of the soft tissues (6). The combi-nation of titanium-reinforced polytetrafluoroethylenemembranes and particulate grafts have shown clini-cal, histologic and long-term success in the treatmentof vertical bone defects of the jaws (57).

A variety of techniques, using various combinationsof natural and synthetic graft materials, can be used

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to achieve vertical alveolar bone augmentation. Mate-rials used for bone augmentation are divided into nat-ural transplants (autografts, allografts and xenografts)and synthetic materials (alloplasts) (22) (Table 1).These graft materials are used clinically based onthe theory that they are osteogenic, osteoinductive,osteoconductive or possess a combination of theseproperties (70).

Treatment protocols for vertical bone augmentationthat are less invasive and less technique sensitive,procedures with a higher degree of reproducibilityand appropriate biomaterials are constantly beingdeveloped in the light of developments in bone-regeneration therapeutics. Extensive studies havereported successful vertical bone regeneration usingbone morphogens or growth factors in combinationwith an array of different scaffolds (61, 71). In fact, theadvent of tissue engineering applied to vertical boneregeneration has exceeded expectations, allowing sig-nificant vertical bone regeneration, even in the mostchallenging defects (61).

Esthetic considerations in guidedbone regeneration

The esthetic area is considered by clinicians andpatients to be the portion visible when smiling,namely the anatomic site ranging between the maxil-lary premolars (30). The smile line varies significantlybetween individuals and between men and women,according to age, anatomy and facial expression. Forsimplicity, clinicians have divided patients accordingto the location of the smile line, into high, medium orlow lip lines (9). Patients usually consider the estheticoutcome of dental implant therapy in the anteriormaxilla an essential factor – often even surpassingfunctional aspects (66). Hence, in the anterior maxil-lae, esthetically unsuccessful treatment outcomesmay lead to disastrous clinical situations that can

only be rectified by removal of implants and sub-sequent tissue-augmentation procedures.

Esthetic parameters that have been defined forconventional dental restorations may also be used forimplant patients during the preoperative planning(3, 30). These parameters may help in defining poten-tial risk factors for esthetic shortcomings. The mainesthetic objectives for implant therapy from a surgicalpoint of view are: achievement of a harmonious gingi-val margin without abrupt changes in tissue height;maintaining intact papillae; and obtaining or preserv-ing a convex contour of the alveolar crest (4). Soft-tissue handling, precise implant placement in arestorative-driven three-dimensional approach andfollow-up procedures represent a variety of chal-lenges for the implant surgeon. These are multipliedwhen the anterior segment is severely atrophic andrequires vertical guided bone regeneration surgery.

Anatomic alterations in the esthetic site

The anterior maxilla goes through significant alveolarremodeling when teeth are absent as a result of previ-ous loss or extraction. After tooth extraction, a meanalveolar bone loss of 1.5–2 mm (vertical) and 40–50%(horizontal) occurs within 6 months (29, 76). Most ofthe alveolar dimensional changes occur during thefirst 3 months (54). If no treatment to restore the den-tition is provided, then continued bone loss occursand up to 40–60% of the ridge volume is lost in thefirst 3 years (63). The loss of vertical bone height leadsto great challenges in dental implant placementbecause of surgical difficulties and anatomic limita-tions. This lack of sufficient bone volume and height,if unresolved, is eventually detrimental to the finalesthetic treatment outcome as well as to implantsuccess and survival (70).

It is crucial to ascertain the location of the naso-palatine foramen and the distance to adjacent teethand to the floor of the nose before performing guided

Table 1. Classification of bone-grafting materials

Autogenous Allogenic Xenogenic Alloplastic

Bone fromsame individual

Bone from same species butanother individual

Bone fromdifferent species

Bone fromsynthetic origin

Block Free frozen bone Animal derived Calcium phosphates

Particulated Freeze-dried bone allograph Coral derived Glass ceramics

– Demineralized freeze-dried bone allograph Calcifying algae Polymers

– Deproteinized bone allograft – Metals

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bone regeneration. Implant contact with neural tissuemay result in failure of osseointegration or lead tosensory dysfunction (23, 40). Recently, Urban et al.(72) reported a patient-centered outcome assessmenton pain or ‘foreign body’ sensation following verticalridge augmentation by lateralization of the naso-palatine nerve and vessels. The authors concludedthat not only was this technique predictable but alsothat patients did not report any clinically measurableimpairments of neurosensory function (72).

A single-tooth gap in the anterior maxilla offers lessof a challenge to the final successful outcome com-pared with a multiple-tooth gap as a result of thepresence of adjacent teeth. These adjacent teeth oftenhave marginal bone levels that may be used as a ref-erence for guided bone regeneration. The healthierthe clinical attachment level of the adjacent teeth, thebetter the prognosis of a successful outcome follow-ing vertical guided bone regeneration and subsequentimplant placement. The greatest limitation when per-forming vertical guided bone regeneration is theinability to regenerate bone beyond existing bonepeaks, in the most coronal position, which is aggra-vated by compromised periodontal attachment ofneighboring teeth. However, recently, authors havepublished case reports in which guided bone regener-ation was coupled to guided tissue regenerationallowing for the formation of papillae next to compro-mised roots (56, 74).

Patients with extended edentulous spaces presentadditional anatomic challenges, making it more diffi-cult to finish the case with a predictable, outstandingesthetic outcome. Understanding the fundamentalplanning objectives in the anterior esthetic zone –

such as tooth axis, interdental closure, gingival con-tours, balance of gingival levels, interdental contacts,tooth dimensions and form – will help produce awax-up that will guide the surgeon toward the goalsnecessary for replacement of the missing teeth andtissue (31). Patients presenting with the loss of a cen-tral and lateral incisor or a lateral incisor and canineare clinically more challenging because the edentu-lous space is smaller than the two central incisorspaces and the inter-implant soft tissue tends to beless voluminous (9). Guided bone regeneration, inthese scenarios, aims at reconstructing enoughvolume of bone to position carefully sized implantsto adapt to the limited mesiodistal space. Oftenthe result is the unpleasant loss of the inter-implant papilla, which alters the harmony of thesmile, as well as the emergence profile of the pros-thetic reconstruction.

Inter-implant papilla

The esthetic appearance of a natural or restored smileresults from balance between the gingival and dentalcomponents (50). In health, the most estheticallypleasing state, the relationship between these twocomponents produces gingival extensions or off-shoots between adjacent teeth. These gingival exten-sions, the interdental papillae, convey a festoonedappearance to the gingival component. In health, thetip of the interdental papilla reaches the contact pointbetween teeth, thereby obliterating the interdentalspace (64). Conversely, the absence of interdentalpapillae in a smile is often a sign of pathology andcauses the formation of interdental ‘black triangles’or ‘black holes’ (55). Interdental black triangles dele-teriously impact on the smile and create discomfortfor the patient as a result of trapping food and plaque,speech alterations and passage of saliva in the spaces.

The aim, after guided bone regeneration withsubsequent implant placement, is to recreate theinter-implant papilla, which can be unpredictable.Numerous attempts to preserve or even reconstructthe inter-implant papillae have been published; how-ever, long-term evaluation of papilla reconstruction isneeded (8, 11). It is important to remind ourselvesthat the interdental papilla depends on the underly-ing alveolar bone anatomy; hence, when this is lost,the papillae are also lost. Prosthetic management ofthe lost tissues may be a viable, although not ideal,option to improve the esthetic appearance of the finalrestorations in the case of loss of inter-implantpapillae (43, 77).

Soft-tissue alterations

The aim of vertical ridge augmentation in the ante-rior region is to provide sufficient bone volume forimplant placement and to provide an estheticallysatisfying result for the patient. Therefore, treatmentplanning should consider both the quantity and thequality of soft tissue in the area to be augmented asa lack of optimal soft tissues can jeopardize the finalesthetic outcome of the whole implant-supportedprosthetic restoration (15, 82). Furthermore, kera-tinized tissues around the implant are advocated toprevent peri-implant diseases (28). For these reasons,the treatment plan may seek to include the use of aconnective tissue graft (10), normally harvested fromthe molar/premolar area of the palate or from themaxillary tuberosity. A connective tissue graft can beused during and/or after a vertical guided bone

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regeneration procedure (56). Using these procedures,it is possible to avoid a concave contour of the buc-cal aspect of the implant mucosa and simultaneouslyto provide adequate keratinized mucosa arounddental implants. The information provided in thissection should be interpreted with caution as theavailable literature is primarily based on casereports. Furthermore, no information is currentlyavailable regarding the possibility of scars generatedby the incisions during flap design when performingbone augmentation.

Esthetic indices

Several indices have been proposed to assess theesthetic appearance of both the reconstruction andthe adjacent mucosa in an objective way (20, 24, 38,65). The most frequently used indices in implant liter-ature are:� Jemt’s Papilla Index (24). The Jemt papilla index is

the oldest and probably the most cited index;however, it only evaluates the presence of theinterdental papilla adjacent to an implant.

� Implant Crown Aesthetic Index (37). This indexevaluates the esthetic result of an implant-supported crown considering nine aspects (fiverelated to the prosthesis and four related to thesoft tissues). The adjacent and the contralateralteeth are used as references.

� the Pink Esthetic Score (20) was developed forsoft-tissue evaluation around single-tooth implantcrowns. It is based on seven variables.

� the Pink and White Esthetic Score (5) is a modifica-tion of the pink esthetic score. The soft-tissueevaluation has been simplified (five parametersinstead of seven) and five variables have beenadded for evaluating the esthetic outcome of thecrown.

� the Complex Esthetic Index (27) is a more recentand articulated index compared with the previousindexes. The authors of this system found that theother indexes did not consider the bone crestbeneath the soft tissue, which is a predictive factorfor esthetic outcome of the implant-supportedrestoration. The 15 variables considered in thisindex are divided into three parts [(i) soft tissue;(ii) predicting factors; and (iii) implant-supportedrestoration], with five parameters each.

In addition, technical equipment, such as photogra-phy, computer software, spectrophotometry and opti-cal scanners, has been applied in clinical trials tomeasure the esthetic features of the mucosa and thesupra-structure (17, 51, 53, 81). However, it must be

noted that variation of intra- and inter-observer agree-ment, depending on the investigators’ specialization,has been reported (21, 37). To the best of our knowl-edge, the above indices are only used in the implant,restorative and prosthetic literature and are rarelyfound in studies reporting outcomes of guided boneregeneration or other bone-augmentation techniques.

Assessment of esthetics and patient-centered outcomes

The literature reporting outcomes of vertical boneaugmentation, irrespective of whether this was per-formed in the posterior or anterior regions, does notprovide information related to patient-centered out-comes and often vague, subjective esthetic parametersare used. For example, papers report ‘. . .acceptableesthetic results. . .’ or ‘. . .harmonic soft tissue architec-ture surrounded the implant restoration. . .’ or ‘. . .thistechnique offers predictable functional and estheticreconstruction. . .’ (16, 56, 61). These descriptions sug-gest that the standard esthetic assessment parametersused in conventional dentistry are seldom used whenassessing outcomes following vertical guided boneregeneration in the esthetic zone. On the contrary,interesting manuscripts have recently been publishedin the implant literature, focusing on esthetic assess-ments and patients’ perception of implant treatment.Two systematic reviews, published in 2012, evaluatedthe literature regarding the professional assessmentof esthetics and patient-centered outcomes inimplant dentistry (7, 34). The authors concluded withthe need for development and application of vali-dated and reproducible assessment methods. Thereis a strong need for a consensus on objective andwell-defined parameters to assess the esthetics inimplant dentistry.

In recent years, dentistry has focused more onpatient-centered care, especially in implant treat-ments where clinicians have evaluated the patients’needs and their satisfaction with treatment outcome.From a patient perspective, implant survival ratesand marginal bone-level changes are not the only rel-evant outcome parameters. Recently, Thoma et al.(67) reported outcomes after implant and bone-regenerative treatment in terms of cost, treatmenttime and patients’ morbidity using standard patientquestionnaires. In order to obtain a clearer under-standing of the patient’s perspective and needs, itis important to use studies with a qualitativedesign. Using such studies, it might be possible toimprove further dental care and quality of life forpatients (25).

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Case presentation

A young patient (a 25-year-old woman, with goodgeneral health status) attended the first consultationassessment concerned about the poor esthetic of hersmile and the mobility of several teeth (Figs 1–3).Following clinical and radiographic examinations(Fig. 4), the patient was diagnosed with severe local-ized aggressive periodontitis. After initial, nonsurgicalperiodontal therapy and wisdom teeth extraction,

four teeth were considered to have a hopeless prog-nosis as a result of the presence of marked soft-tissue recession and bone loss. Therefore, teeth 1.1,2.1, 2.3 and 2.4 were extracted (Fig. 5) and aridge-preservation procedure, with deproteinizedbovine bone (Geistlich Bio-Oss�; small granules;Geistlich S€ohne AG, Geistlich Sons Ltd., Manchester,

Fig. 1. The patient’s initial situation, frontal view.

Fig. 2. The patient’s initial situation, particularly of teeth2.3 and 2.4.

Fig. 3. The patient’s initial situation, particularly of teeth1.1 and 2.1.

Fig. 4. Panoramic radiograph of the patient showingsevere bone loss between teeth 1.1 and 2.1, between teeth2.3 and 2.4 and in the posterior regions. Only four teethwere considered hopeless.

Fig. 5. Occlusal view after extraction of the four hopelessteeth (1.1, 2.1, 2.3 and 2.4).

Fig. 6. Frontal view showing ridge preservation afterextraction of the four hopeless teeth (1.1, 2.1, 2.3 and 2.4).

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UK) and connective tissue punch, was performed(Figs 6–11). A resin retained temporary MarylandBridge was delivered to ensure good esthetics for thepatient. During the healing phase, periodontal surg-eries (osseous resective surgeries) were performed onthe remaining teeth to treat periodontitis.

Six months post-extraction, vertical and horizontalbone ridge augmentation procedures were performedsimultaneously in both edentulous sites following theguided bone regeneration technique. The latter

was performed using two nonresorbable, titanium-reinforced, expanded-polytetrafluoroethylene mem-branes (Gore-tex�; regenerative membrane titaniumreinforced TR6Y; W. L. Gore & Associates, Inc., Flag-staff, AZ, USA) fixed to the residual bony walls byeight pins (FRIOS� Membrane Tacks; Dentsply Corp.York, PA, USA), two tenting screws (Maxil�; TitaniumMicro-screw 1.5 9 9 mm; OMNIA S.p.A, Fidenza,Italy) and a 3:1 (vol/vol) mixture of autologous bonechips (harvested with a bone scraper in the recipientarea) and deproteinized bovine bone (Geistlich Bio-Oss�. small granules; Geistlich S€ohne AG; Figs 12–22).

Fig. 7. Two connective tissue punches were positioned onthe sites of extracted teeth 1.1 and 2.1 to cover the bioma-terial inserted into the socket.

Fig. 8. The same ridge preservation technique using a con-nective tissue punch (as shown in Figs 6 and 7) at the sitesof extracted teeth 2.3 and 2.4.

Fig. 9. Panoramic radiograph showing the sockets filledwith the xenograft.

Fig. 10. The surgical site after 1 week of healing.

Fig. 11. The surgical site after 1 month of healing.

Fig. 12. A full-thickness buccal flap with two releasingincisions was elevated from the distal portion of tooth 1.3to the distal portion of tooth 2.5. The palatal flap (withoutreleasing incisions) was also elevated.

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Both sites healed uneventfully (Fig. 23) and,4 months later, the patient started orthodontic treat-ment to correct tooth position and optimize spacefor implant placement. Eight months after the aug-mentation surgery, the two nonresorbable mem-branes, two tenting screws and eight fixation pins

were removed (Figs 24 and 25) and four implantswere inserted into the regenerated bone (Fig. 26).Two 13 9 3.75 mm MKIII implants (Nobel Biocare,Kloten, Switzerland) were inserted in tooth sites 1.1and 2.1; and two 13 9 4 mm Nobel Speedy implants

Fig. 13. The atrophic crest in an occlusal view. The whitearrow indicates the nasopalatine canal: the structures con-tained in it were removed and the empty space wasincluded in the regeneration procedure.

Fig. 14. The tenting screw was positioned between teeth1.1 and 2.1; the amount of vertical bone regenerated isapproximately 4 mm.

Fig. 15. The second tenting screw was positioned betweenteeth 2.3 and 2.4. Similarly to that shown in Fig. 14, verti-cal bone augmentation of 4 mm was needed.

Fig. 16. Tooth sites 1.1 and 2.1 were filled with a mixtureof autologous bone chips and xenograft; the nonresorbablemembrane was fixed on the palatal site.

Fig. 17. The same phase of surgery described in Fig. 16, intooth sites 2.3 and 2.4.

Fig. 18. The nonresorbable membrane covered the mix ofparticulated bone and was carefully adapted onto the graftand the bone surfaces of tooth sites 1.1 and 2.1.

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(Nobel Biocare) were inserted in tooth sites 2.3 and2.4. In addition to implant placement, deproteinizedbovine bone xenograft particles (Geistlich Bio-Oss�;small granules; Geistlich S€ohne AG) and two resorb-able collagen matrixes (Geistlich Bio-Gide�; GeistlichS€ohne AG) were positioned on the buccal portion toenhance and protect the newly regenerated horizon-tal bone volume (Figs 27–32).

Four months post-implant placement, the soft-tis-sue volume of the two regenerated areas was aug-mented using two collagen barrier matrices (GeistlichMucograft�; Geistlich S€ohne AG; Figs 33–36). Onemonth after soft-tissue grafting, four healing abut-ments were connected to the implants using a small-punch approach in order not to disturb the newlyformed soft and hard tissues (Figs 37 and 38). Oneweek later, an impression of the implant position wastaken, and screw-retained provisional prostheses

Fig. 19. Occlusal view of the nonresorbable membrane attooth sites 2.3 and 2.4.

Fig. 20. Occlusal view after suturing. It is possible to seethe 5/0 expanded polytetrafluoroethylene (GORE-TEX�

Suture CV5; W. L. Gore & Associates, Inc., Flagstaff, AZ,USA) internal mattress suture and the 6/0 polypropylene(Prolene 6.0 Ethicon; Johnson & Johnson Inc., New Bruns-wick, NJ, USA) interrupted suture.

Fig. 21. Frontal view 2 weeks after the augmentationsurgery.

Fig. 22. Panoramic radiograph showing the two regener-ated sites in which the tenting screws and the fixation pinsare clearly visible.

Fig. 23. Occlusal view before surgically opening the flapsto remove the nonresorbable membrane.

Fig. 24. Vestibular view of the two nonresorbable mem-branes in situ.

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Fig. 25. The newly formed bone was visible after removingthe nonresorbable membranes.

Fig. 26. Occlusal view of the four implants placed in theregenerated bone.

Fig. 27. A second horizontal bone-augmentation surgerywas performed at time of implant placement; Bio-oss�

particles are positioned on the 1.1 and 2.1 buccal areas.

Fig. 28. Xenograft covered by two resorbable membranes.

Fig. 29. Panoramic radiograph showing the implant posi-tioned in the upper jaw.

Fig. 30. Frontal view of the healing at the surgical sitesafter 2 weeks.

Fig. 31. Closer view of the buccal contour at sites 1.1 and2.1 showing good soft-tissue contour.

Fig. 32. Frontal view of the 1.1 and 2.1 sites after implantplacement. Vertical gain of the alveolar crest is clearlyvisible.

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Fig. 33. Frontal view of the soft-tissue augmentation sur-gery; a partial-thickness flap was raised.

Fig. 34. The Mucograft� positioned under the flap.

Fig. 35. Occlusal view 2 weeks after soft-tissue augmenta-tion surgery.

Fig. 36. Buccal aspect following 2 weeks of healing afterthe soft-tissue augmentation procedure.

Fig. 37. Occlusal view of the two regenerated sites beforethe connection of the healing abutments.

Fig. 38. The four implants were uncovered with the aid ofa soft-tissue punch and then connected to four healingabutments.

Fig. 39. The first implant screw-retained dental prosthesis.

Fig. 40. Frontal view of the transfers connected to theimplants for the final impression.

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were positioned after a further 14 days (Fig. 39). Thefour definitive zirconia abutments were screwed after3 months (Figs 40–41); a second, luted provisionalprosthesis was fabricated (Fig. 42) in order to maxi-mize the soft-tissue adaptation and tooth form.

When the result was satisfactory for both thepatient and the prosthodontist, the case was finalizedwith two metal-free fixed dental prostheses luted onzirconia abutments (Figs 43 and 44).

Conclusion

Advances in biomaterials research and the develop-ment of new and improved surgical techniques andarmamentarium have resulted in ever-increasing pos-sibilities to regenerate bone in the most challengingdefects. In addition to functional and health-relatedaspects, the visual appearance of the reconstructionand surrounding soft tissues has become an impor-tant factor for clinical success in esthetic sites.Some implant, restorative and prosthetic studies reportesthetic outcomes (using well-defined indices) andpatient-centered outcomes. However, literature report-ing bone atrophies treated using vertical and/orhorizontal guided bone regeneration often do not eval-uate the final esthetic result or patient-centered out-comes. Future studies on guided bone regenerationshould focus on investigating the esthetic results as theprimary outcome variable as well as patient-reportedoutcomes.

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Fig. 41. The polyether impression was taken to fabricatefour zirconia definitive abutments.

Fig. 42. The second provisional prosthesis luted to the zir-conia abutments.

Fig. 43. The smile of the patient showing the final metal-free prosthesis.

Fig. 44. Intra-oral view of the final restoration.

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