Dentistry Journal

Case Report Minimally Invasive Diastema Restoration with Prefabricated Sectional Veneers

Claudio Novelli 1 and Andrea Scribante 1,2,*

1 Private Practice, DENS Centro Medico Lombardo, 20124 Milan, Italy; [email protected] 2 Unit of Orthodontics and Pediatric Dentistry, Section of Dentistry, Department of Clinical, Surgical, Diagnostic and Pediatric Sciences, University of Pavia, 27100 Pavia, Italy * Correspondence: [email protected]

Received: 28 March 2020; Accepted: 19 June 2020; Published: 24 June 2020

Abstract: This case report presents a new technique for sectional veneer fabrication and diastema restoration with a prefabricated composite veneer. For the purpose of diastema restoration, a prefabricated sectional veneer provides the same beneﬁts of a traditional ceramic sectional veneer (highly esthetic restoration with no need for tooth preparation) but involves a less technically demanding and time-consuming clinical procedure and a less delicate restoration with a reduced risk of accidental breakage and post-bonding crack formation. The technique presented in this case report bridges the gap between a direct and indirect technique for diastema restoration and introduces a new treatment option to close anterior spacing with a highly esthetic sectional veneer in a predictable and timely manner.

Keywords: diastema; restoration; sectional veneer; ceramic veneer; composite veneer; prefabricated veneer

1. Introduction Thanks to the combination of excellent esthetic outcomes and no sacrifices related to healthy tooth structure, orthodontic treatment is frequently advocated to close anterior diastemas [1–3]. However, when a Bolton discrepancy is detected, orthodontic treatment alone cannot establish proximal contacts with proper vertical and horizontal overlaps and restorative treatment is indicated to close the residual spaces [4–6]. Several treatment options are available for minimally invasive diastema restoration, including the recently introduced injectable composite resin technique, composite template technique and the prefabricated veneer technique [7–10]. However, direct composite restoration and indirect ceramic veneers are still the most popular minimally invasive treatment options to close the anterior spacing and restore the natural appearance of the smile. Direct composites can produce a very lifelike diastema restoration in a convenient single appointment with no need for tooth preparation. However, the technique requires advanced sculpting and finishing skills to achieve an optimally polished restoration with ideal anatomic form and no residual black triangle in the gingival embrasure [11–13]. Because of these limitations, some dentists prefer to depend on laboratory-fabricated ceramic veneers, especially for large diastemas that are more challenging to close with a direct technique. Ceramic veneers can produce a diastema restoration with exquisite esthetics and excellent longevity, but the technique requires a technically demanding and time-consuming clinical procedure, not to mention the sacrifice of a healthy tooth structure to allow space for the restorative material. Sometimes, a noninvasive veneer preparation is possible where the buccal surface remains intact, but the margin of the veneer still requires tooth reduction, especially in the interproximal area where the margin has to be moved lingually and sub-gingivally in order to produce effective space management and soft tissue contouring [14,15]. Ultimately, either direct composites or indirect ceramic veneers can serve very well for the purpose of diastema restoration; however, both techniques have

Dent. J. 2020, 8, 60; doi:10.3390/dj8020060 www.mdpi.com/journal/dentistry Dent. J. 2019, 7, x FOR PEER REVIEW 2 of 12 directDent. J. 2020composite, 8, 60 s or indirect ceramic veneers can serve very well for the purpose of diastema2 of 12 restoration; however, both techniques have intrinsic limitations for dentists who are looking for a minimally invasive and simple technique to close anterior spacings. This paper presents an intrinsicDent. limitationsJ. 2019, 7, x FOR for PEER dentists REVIEW who are looking for a minimally invasive and simple technique2 of 12 to alternative technique for diastema restoration with a prefabricated composite sectional veneer. close anterior spacings. This paper presents an alternative technique for diastema restoration with Prefabricateddirect composite composites or indirect veneers ceramic are veneerpre-shaped,s can serve pre- polished very well composite for the purpose laminates of diastema available in a prefabricated composite sectional veneer. differentrestorat shapesion; however and sizes, both for techniques direct bonding have intrinsic to the deservinglimitations toothfor dentist withs whoa complementary are looking for shade a - Prefabricatedminimally invasive composite and simple veneers technique are pre-shaped, to close anterior pre-polished spacings. composite This paper laminates presents available an matched composite resin [16–18]. This technique is indicated to treat a large variety of esthetic in dialternativefferent shapes technique and for sizes diastema for direct restoration bonding with a to prefabricated the deserving compo toothsite sectional with a veneer. complementary problems and to produce a veneer with a proper size, accurate anatomy and highly polished surface shade-matchedPrefabricated composite composite resin veneers [16–18]. are This pre technique-shaped, pre is-polished indicated composite to treat alaminates large variety available of estheticin in a single appointment with a reduced number of clinical steps. One of the main innovations problemsdifferent and shapes to produce and sizes a veneer for direct with bonding a proper to size, the accuratedeserving anatomy tooth with and a complementary highly polished shade surface- in introduced by the prefabricated composite veneer technique is the possibility to customize the veneer a singlematched appointment composite with resin a reduced [16–18]. number This technique of clinical is steps. indicated One to of treatthe main a large innovations variety of introduced esthetic by chairside using conventional composite instruments. In the case presented in this report, the the prefabricatedproblems and compositeto produce veneera veneer technique with a proper is the size, possibility accurate anatomy to customize and highly the veneer polished chairside surface using prefabricatedin a single composite appointment veneer with was a reduced customized number chairside of clinical with steps. a diamond One of theseparating main innovatio disc tons fit the conventional composite instruments. In the case presented in this report, the prefabricated composite size ofintroduced the diastema by the to prefabricated be closed. Then, composite a sectional veneer veneertechnique is readyis the possibility for bonding to customize to the spaced the veneer dentition veneer was customized chairside with a diamond separating disc to fit the size of the diastema to be and closechairsides the usingdiastema conventional in a single composite appointment instruments. with no In sacrifice the case of presentedhealthy tooth in this structure. report, the closed. Then, a sectional veneer is ready for bonding to the spaced dentition and closes the diastema in Thisprefabricated technique composite bridges veneer the was gap customized between achairside direct w andith a an diamond indirect separating technique disc forto fit diastema the a single appointment with no sacrifice of healthy tooth structure. restorationsize of theand diastema introduces to be aclosed. new Then,treatment a sectional option veneer to close is ready anterior for bonding spacing to the with spaced a highly dentition esthetic Thisand close techniques the diastema bridges in the a single gap between appointment a direct with and no ansacrifice indirect of healthy technique tooth for structure. diastema restoration sectional veneer in a predictable and timely manner. and introducesThis technique a new treatment bridges option the gap to between close anterior a direct spacing and an with indirect a highly technique esthetic for sectional diastema veneer in a predictablerestoration and and introduces timely manner. a new treatment option to close anterior spacing with a highly esthetic 2. Casesectional Presentation veneer in a predictable and timely manner. 2. CaseThe Presentation patient was a 27-year-old lady referred by her orthodontist for restorative treatment of 2. Case Presentation multipleThe anterior patient wasmaxillary a 27-year-old diastemas lady (Figure referred 1). The by unit her orthodontistinternal review for board restorative approved treatment the case of The patient was a 27-year-old lady referred by her orthodontist for restorative treatment of reportmultiple (2019 anterior-0923) maxillary on 23 September diastemas 2019. (Figure Clinical1). The and unit radiologic internal reviewal examination board approved showed the healthy case multiple anterior maxillary diastemas (Figure 1). The unit internal review board approved the case incisorsreport (2019-0923) with no previous on 23 Septemberrestorations 2019. and no Clinical signs of and periodontal radiological disease examination (Figure 2). showed Measurements healthy from reportthe study (2019 models-0923) on revealed 23 September a significant 2019. Clinical Bolton and discrepancy radiological and examination a 1.9 mm showed diastema healthy between incisorsincisors with with no previousno previous restorations restorations and and no no signssigns of of periodontal periodontal disease disease (Figure (Figure 2). 2Measurements). Measurements central incisors associated with 1.1 mm bilateral diastemas between central and lateral incisors. fromfrom the studythe study models models revealed revealed a a significant significant BoltonBolton discrepancy discrepancy and and a 1.9 a 1.9 mm mm diastema diastema between between centralcentral incisors incisors associated associated with with 1.1 1.1 mm mm bilateral bilateral diastemasdiastemas between between central central and and lateral lateral incisors. incisors.

FigureFigure 1. 1. PPreoperative Preoperativereoperative fullfull full-face-face-face view view view.. .

Figure 2. Preoperative retracted view.

Dent. J. 2019,, 7,, xx FORFOR PEERPEER REVIEWREVIEW 3 of 12 Dent. J. 2020, 8, 60 3 of 12 Figure 2. Preoperative retracted view. Because of the young age of the patient, a noninvasive treatment with sectional veneers was Because of the young age of the patient, a noninvasive treatment with sectional veneers was recommended to close the spaces and restore the natural appearance of the smile. However, the size recommended to close the spaces and restore the natural appearance of the smile. However, the size of the spaces to be closed was a possible contraindication for restoration with sectional veneers of the spaces to be closed was a possible contraindication for restoration with sectional veneers because the increased tooth width could result in altered width-to-length ratio and less than ideal because the increased tooth width could result in altered width-to-length ratio and less than ideal tooth proportions. Ideal tooth proportions have been extensively discussed in the literature and many tooth proportions. Ideal tooth proportions have been extensively discussed in the literature and many diﬀerent ratios have been introduced to be used as esthetic guidelines for tooth dimensions [19–21]. different ratios have been introduced to be used as esthetic guidelines for tooth dimensions [19–21]. However, these ratios rarely occur in smiles deemed attractive by laypeople and dental professionals However, these ratios rarely occur in smiles deemed attractive by laypeople and dental professionals and their rigid application to predict ideal tooth size is controversial [22–26]. An alternative approach and their rigid application to predict ideal tooth size is controversial [22–26]. An alternative approach to provide a guideline for ideal tooth dimensions is to use average tooth size in the human population to provide a guideline for ideal tooth dimensions is to use average tooth size in the human population as a reference. Anatomical values of tooth dimensions are well established in the literature and show as a reference. Anatomical values of tooth dimensions are well established in the literature and show that, although tooth width and length varies with gender, age and race, tooth width/length ratio that, although tooth width and length varies with gender, age and race, tooth width/length ratio in in the upper anterior dentition is a stable, reference falling within a range of 72% to 85% [27–29]. the upper anterior dentition is a stable, reference falling within a range of 72% to 85% [27–29]. For the For the patient presented in this report, the diagnostic wax-up revealed a favorable 82% width-to-length patient presented in this report, the diagnostic wax-up revealed a favorable 82% width-to-length ratio ratio and conﬁrmed that, despite the moderate size of the diastemas, restoration with sectional veneers and confirmed that, despite the moderate size of the diastemas, restoration with sectional veneers could be completed without unbalancing natural tooth proportions (Figure3). could be completed without unbalancing natural tooth proportions (Figure 3).

Figure 3. TThehe diagnostic wax wax-up-up reveals a favorable 82% width width-to-length-to-length ratio ratio of the teeth restored with additional restorations.restorations.

Once the preliminary measurements were completed and the treatment plan with sectional veneers was approved by the patient, the clinical procedure started with fitting ﬁtting the prefabricated veneers to the size of the diastema. The prefabricated composite veneers veneers for for the the patient ppresentedresented in this case report (Edelweiss Veneers, Edelweiss Dentistry, Wolfurt, Austria)Austria) areare fabricatedfabricated with a nanohybrid composite cured with high temperature and high pressure to produce a veneer with improved mechanical properties compared to a conventionalconventional composite restoration [ 3030,31,31]. In In addition addition to to the the heat/pressure heat/pressure curing processprocess,, the tested veneers also feature a proprietary laser sintering technology that extracts the the resin resin component from the composite shell and produces a veneer with high high inorgani inorganicc content and a highly highly esthetic, laser laser-sintered-sintered surface [3232,33,33]] (Figure(Figure4 4).).

Figure 4. PrefabricatedPrefabricated laser laser-sintered-sintered veneers veneers..

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Edelweiss PrefabricatedPrefabricated VeneersVeneers are are available available in fourin four sizes sizes (XS, (XS, S, M, S, L) M, and L) aand custom a custom sizing sizing guide guideis included is included in the systemin the system to select to theselect veneer the veneer that best that ﬁts best the fits deserving the deserving tooth. Fortooth. the For patient the patient in this incase this report, case report small, veneers small veneers were selected. were selected. After veneer veneer size size selection selection,, the the width width of ofthe the diastema diastema was was measured measured with with a digital a digital caliper caliper and transferredand transferred to the to veneer the veneer using using a thin a thinmarker marker (Figure (Figure 5a,b).5a,b).

Dent. J. 2019, 7, x FOR PEER REVIEW 4 of 12

Edelweiss Prefabricated Veneers are available in four sizes (XS, S, M, L) and a custom sizing guide is included in the system to select the veneer that best fits the deserving tooth. For the patient in this case report, small veneers were selected. After veneer size selection, the width of the diastema was measured with a digital caliper and transferred to the veneer using a thin marker (Figure 5a,b).

(a)

(b )

Figure 5. ((aa)) The The size size of of the the( bdiastema diastema) is is measured measured with with a a digital digital caliper caliper;; ( b) the size of the diastema is Figure 5. (a) Thetransferred size of the diastema to the isveneer measured with with a a thin digital marker. caliper; (b) the size of the diastema is transferred to the veneer with a thin marker. A diamond separating disc (ZR943, Komet, Lemgo, Germany)was used used to to cut cut the veneer along A diamond separating disc (ZR943, Komet, Lemgo, Germany)was used to cut the veneer along the marker line and produce a sectional veneer that exactly ﬁtsfits thethe spacespace toto bebe closedclosed (Figure(Figure6 6a).a). the marker line and produce a sectional veneerDent. that J.exactly 2019, 7, fitsx FOR the PEER space REVIEW to be closed (Figure 6a). 5 of 12

(a) (b)

Figure 6. (a) A diamond separatingFigure 6. ( disca) A diamond is used toseparating cut the disc veneer; is used (b to) cut the the sectional veneer; ( veneerb) the sectional clicks veneer clicks into place. into place. (a) After trying the sectional veneer in its eventual position to confirm the size and shape (Figure 6b), a retraction cord was packed around the tooth (Ultrapack size 00, Ultradent, South Jordan, UT, USA) to prevent contamination from the crevicular fluid and to produce the gentle displacement of the soft tissue. The cord was positioned tooth by tooth only when the veneer was ready to be delivered and was removed as soon as isolation was no longer necessary. A thin retraction cord was used since the try-in showed how the emergence profile of the sectional veneer already produced effective soft tissue compression with no residual black triangle and no need for extra soft tissue displacement. Another reason for using a thin retraction cord was the thin scalloped gingival phenotype and the risk of stressing the delicate soft tissue. The Edelweiss Veneer requires no sandblasting, no acid etching and no silane application for bonding. However, the manufacturer recommends internal conditioning with a dedicated resin primer (Veneer Bond, Edelweiss Dentistry, Wolfurt, Austria) to promote chemical adhesion and increase bond strength between the highly inorganic composite laminate and the luting composite. After Veneer Bond application, the prefabricated Veneers are ready for bonding using a complementary nanohybrid composite resin available in several dentin and enamel shades (Edelweiss NH, Edelweiss Dentistry, Wolfurt, Austria). Small- and medium-sized sectional veneers (i.e., diastema width <2 mm) are usually bonded with an enamel shade only. Larger sectional veneers are usually bonded with the combination of a dentin shade in the gingival area and an enamel shade in the incisal area in order to produce gingival–incisal color gradation and an increased background masking effect. For the patient presented in this paper, all the sectional veneers were bonded with an enamel shade only (Figure 7).

Figure 7. Sectional veneer loaded with enamel shade.

Once the sectional veneer was loaded with the selected composite shade and was therefore ready for bonding, the tooth was etched with 35% orthophosphoric acid followed by the application of a single-step adhesive, according to the manufacturer instructions (Peak Universal, Ultradent, South Jordan, UT, USA). Then, the first sectional veneer was seated in position and gently pressed until it

Dent. J. 2019, 7, x FOR PEER REVIEW 5 of 12

(b)

Dent. J.Figure2020, 8 6., 60 (a) A diamond separating disc is used to cut the veneer; (b) the sectional veneer clicks into5 of 12 place.

After tryingtrying thethe sectionalsectional veneer veneer in in its its eventual eventual position position to to confirm confirm the the size size and and shape shape (Figure (Fig6ureb), 6b),a retraction a retraction cord cord was packedwas packed around around the tooth the (Ultrapacktooth (Ultrapack size 00, size Ultradent, 00, Ultradent, South Jordan, South UT,Jordan, USA) UT to, preventUSA) to contaminationprevent contamination from the from crevicular the crevicular fluid and fluid to produce and to produce the gentle the displacement gentle displacement of the soft of thetissue. soft The tissue cord. The was cord positioned was positioned tooth by tooth tooth by only tooth when only the when veneer the was veneer ready was to be ready delivered to be deliveredand was removed and was asremoved soon as as isolation soon as was isolation no longer was necessary.no longer necessary. A thin retraction A thin cordretraction was used cord since was usedthe try-in since showed the try- howin showed the emergence how the profileemergence of the profile sectional of the veneer sectional already veneer produced already eff ectiveproduced soft effectivetissue compression soft tissue withcompression no residual with black no residual triangle black and notriangle need forand extra no need soft tissuefor extra displacement. soft tissue Anotherdisplacement reason. Another for using reason a thin retraction for using cord a thin was retraction the thin scalloped cord was gingival the thin phenotype scalloped and gingival the risk phenotypeof stressing and the delicatethe risk of soft stressing tissue. the delicate soft tissue. The Edelweiss Veneer requires nono sandblasting,sandblasting, no acid etching and no silane application for bondingbonding.. However, However, the the manufacturer manufacturer recommends recommends internal internal conditioning conditioning with awith dedicated a dedicated resin primer resin (Veneerprimer (VeneerBond, Edelweiss Bond, Edelweiss Dentistry, Dentistry, Wolfurt, Austria) Wolfurt to, promoteAustria) chemicalto promote adhesion chemical and adhesion increase bond and increasestrength bond between stre thength highly between inorganic the highly composite inorganic laminate composite and the laminate luting composite.and the luting composite. After Veneer Veneer Bond Bond application application,, the the prefabricated prefabricated Veneers Veneers are are ready ready for for bonding bonding using using a complementarya complementary nanohybrid composite composite resin resin available available in several in several dentin and dentin enamel and shades enamel (Edelweiss shades (EdNH,elweiss Edelweiss NH, Dentistry, Edelweiss Wolfurt, Dentistry, Austria). Wolfurt Small-, Austria) and medium-sized. Small- and medium sectional-size veneersd sectional (i.e., diastema veneers width(i.e., diastema<2 mm) width are usually <2 mm) bonded are usually with bonded an enamel with shade an enamel only. Largershade only. sectional Larger veneers sectional are veneers usually arebonded usually with bonded the combination with the combination of a dentin shade of a dentin in the shade gingival in areathe gingival and an enamelarea and shade an enamel in the incisalshade inarea the in incisal order toarea produce in order gingival–incisal to produce gingival color gradation–incisal color and gradation an increased and background an increased masking background effect. maskingFor the patient effect. presentedFor the patient in this presented paper, all in the this sectional paper, all veneers the sectional were bonded veneers with were an bonded enamel with shade an enamonly (Figureel shade7). only (Figure 7).

Figure 7. SSectionalectional veneer loaded with enamel shade shade..

Once the sectional veneer was loaded loaded with the the selected selected composite composite shade shade and and was was therefore therefore ready ready for bonding, t thehe t toothooth was was etched etched with with 35% 35% orthophosphoric orthophosphoric acid acid followed followed by by the the application application of ofa singlea single-step-step adhesive adhesive,, according according to to the the manufacturer manufacturer instructions instructions (Peak (Peak Universal, Universal, Ultradent, South Jordan, UT, USA).USA). Then,Then, the firstfirst sectionalsectional veneer was seated in position and gently pr pressedessed until it made contact with the adjacent tooth (Figure8). A thin spatula (IPC, American Eagle Instruments, Missoula, MT, USA) was used to sculpt the extra composite and achieve optimal adaptation between the veneer and the tooth (Figure9). Finally, the veneer was light cured for 20 s from the lingual direction plus 20 s from the buccal direction using a high-power curing light (Demi Plus, Kerr Corporation, Brea, CA, USA). Once curing was completed, the margins of the sectional veneer were finished and polished with conventional composite instruments. The tested prefabricated veneers do not require special equipment and can be effectively polished with most of the commercially available polishing systems for nanohybrid composite resin. In the case presented in this report, a 50-micron needle point diamond bur (Brasseler DET3F, Brasseler, Savannah, GA, USA) was used to smooth the extra composite, followed by a silicone cup (Identoflex Composite Polisher, Ravelli, Milano, Italy) to remove the residual scratches (Figure 10) and a paper finishing strip (Sof-Lex, ESPE 3M) to polish the interproximal area (Figure 11). Finishing and polishing is limited to the margins of the sectional veneer and no instrumentation is Dent. J. 2019, 7, x FOR PEER REVIEW 6 of 12 Dent. J. 2019, 7, x FOR PEER REVIEW 6 of 12 made contact with the adjacent tooth (Figure 8). A thin spatula (IPC, American Eagle Instruments, made contact with the adjacent tooth (Figure 8). A thin spatula (IPC, American Eagle Instruments, Missoula, MT, USA) was used to sculpt the extra composite and achieve optimal adaptation between Missoula,Dent. MT, J. 2020 USA), 8, 60 was used to sculpt the extra composite and achieve optimal adaptation6 of 12 between the veneer and the tooth (Figure 9). Finally, the veneer was light cured for 20 s from the lingual the veneer and the tooth (Figure 9). Finally, the veneer was light cured for 20 s from the lingual direction plus 20 s from the buccal direction using a high-power curing light (Demi Plus, Kerr directionrequired plus 20 on the s from buccal theand lingual buccal surfaces, direction since prefabricatedusing a high veneers-power are pre-shapedcuring light and pre-polished (Demi Plus, Kerr Corporation, Brea, CA, USA). Corporation,to the idealBrea, anatomic CA, USA). form, with accurate superficial anatomy and a high-gloss, laser-sintered surface.

Figure 8. Prefabricated veneer seated in position until connection with the adjacent tooth. Figure 8.Figure Prefabricated 8. Prefabricated veneer veneer seated seated in in position position untiluntil connection connection with with the adjacent the adjacent tooth. tooth.

FigureFigure 9. The 9. extraThe extra composite composite is iscarefully carefully sculptedsculpted with with an ultrathinan ultrathin spatula. spatula. Dent. J. 2019, 7, x FORFigure PEER 9. REVIEW The extra composite is carefully sculpted with an ultrathin spatula. 7 of 12

Once curing was completed, the margins of the sectional veneer were finished and polished with Once curing was completed, the margins of the sectional veneer were finished and polished with conventional composite instruments. The tested prefabricated veneers do not require special conventional composite instruments. The tested prefabricated veneers do not require special equipment and can be effectively polished with most of the commercially available polishing systems equipment and can be effectively polished with most of the commercially available polishing systems for nanohybrid composite resin. In the case presented in this report, a 50-micron needle point for nanohybrid composite resin. In the case presented in this report, a 50-micron needle point diamond bur (Brasseler DET3F, Brasseler, Savannah, GA, USA) was used to smooth the extra diamond bur (Brasseler DET3F, Brasseler, Savannah, GA, USA) was used to smooth the extra composite, followed by a silicone cup (Identoflex Composite Polisher, Ravelli, Milano, Italy) to composite, followed by a silicone cup (Identoflex Composite Polisher, Ravelli, Milano, Italy) to remove the residual scratches (Figure 10) and a paper finishing strip (Sof-Lex, ESPE 3M) to polish the remove the residual scratches (Figure 10) and a paper finishing strip (Sof-Lex, ESPE 3M) to polish the interproximal area (Figure 11). Finishing and polishing is limited to the margins of the sectional interproximal area (Figure 11). Finishing and polishing is limited to the margins of the sectional veneer and no instrumentation is required on the buccal and lingual surfaces, since prefabricated veneer and no instrumentation is required on the buccal and lingual surfaces, since prefabricated veneers are pre-shaped and pre-polished to the ideal anatomic form, with accurate superficial veneers are pre-shaped and pre-polished to the ideal anatomic form, with accurate superficial anatomy and a high-gloss, laser-sintered surface. anatomy and a high-gloss, laser-sintered surface. FigureFigure 10. 10. FinishingFinishing thethe margins. margins.

Figure 11. Finishing the interproximal spaces.

Figure 12. Post-operative full-face view.

Dent. J. 2019, 7, x FOR PEER REVIEW 7 of 12

Figure 10. Finishing the margins.

Dent. J. 2020, 8, 60 7 of 12 Figure 10. Finishing the margins.

Figure 11. Finishing the interproximal spaces.

Once all the veneers were bonded in position, the patient was dismissed and rescheduled for a post-operative evaluation two weeks later. At the recall appointment, a functional evaluation (absence of fractures, marginal adaptation), a biological evaluation (soft tissue response, post- operative sensitivity) and an esthetic evaluation (gloss, color matching) were completed and were fully satisfactory (Figures 12 Figureand 13 11.). As Finishing a final the recommendation interproximal spaces.spaces, oral. hygiene instructions for the interproximal dental spaces were reviewed and the patient was rescheduled for a regular 6-month followOnce-up appointment.all the veneers were were bonded bonded in in position position,, the the patient patient was was dismissed dismissed and and resc rescheduledheduled for for a apost post-operative-Theoperative highly evaluation translucentevaluation two two and weeks weeks glossy later. later. surface At At the of the the recall recall Veneer appointment appointment, produced, a a optimal functional esthetics evaluation evaluation with (absenceinvisible(absence oftransition of fractures, fractures, between marginal marginal the adaptation), veneer adaptation), and a biologicalthe a tooth.biological evaluationThe lack evaluation of (soft tooth tissue (softpreparation response, tissue response,and post-operative the single post- sensitivity)appointmentoperative sensitivity) and procedure an esthetic and with evaluationan noesthetic impression (gloss, evaluation colors, no matching)t emporaries(gloss, color were and matching) completed no try-ons were and minimized werecompleted fully the satisfactory and stress were for (Figuresthefully soft satisfactory 12 tissues and 13 and ().Fig As greatlyures a ﬁnal 12 and contributedrecommendation, 13). As a to final the oral recommendation reduced hygiene post instructions-operative, oral hygiene for discomfort the interproximal instructions and excellent for dental the spacesacceptanceinterproximal were by reviewed thedental patient. spaces and the were patient reviewed was rescheduled and the patient for a regularwas rescheduled 6-month follow-up for a regular appointment. 6-month follow-up appointment. The highly translucent and glossy surface of the Veneer produced optimal esthetics with invisible transition between the veneer and the tooth. The lack of tooth preparation and the single- appointment procedure with no impressions, no temporaries and no try-ons minimized the stress for the soft tissues and greatly contributed to the reduced post-operative discomfort and excellent acceptance by the patient.

Dent. J. 2019, 7, x FOR PEER REVIEW Figure 12. PostPost-operative-operative full full-face-face view view.. 8 of 12

Figure 12. Post-operative full-face view.

Figure 13. PostPost-operative-operative retracted retracted view view..

3. DiscussionThe highly translucent and glossy surface of the Veneer produced optimal esthetics with invisible transition between the veneer and the tooth. The lack of tooth preparation and the single-appointment This paper presents an alternative technique for minimally invasive diastema restoration with procedure with no impressions, no temporaries and no try-ons minimized the stress for the soft sectional veneers. The sectional veneer technique was introduced as a variation on the traditional ceramic veneer technique for highly esthetic veneer restoration with no need for tooth preparation [34,35]. However, despite the combination of excellent esthetics and no sacrifice of the tooth structure, ceramic sectional veneers have failed to enter the mainstream of general dentistry because of the technically demanding clinical procedure and the delicate laboratory fabrication process. Another limitation to the popularity of the ceramic sectional veneer technique is the high risk of accidental breakage and post-bonding crack formation on the knife-edged margins due to the reduced ceramic thickness and the unfavorable ceramic/composite thickness ratio [36–38]. In the case presented in this paper, the sectional veneer technique was reinterpreted using a prefabricated composite veneer. The prefabricated composite veneer technique was originally launched in the late 1970s (Mastique Veneer System, Caulk Dentsply) but with limited success because the large glass filler technology available at the time did not provide adequate esthetics and durability [39–41]. However, the concept of a prefabricated veneer was rejuvenated about 40 years later thanks to the introduction of contemporary composite resin with improved mechanical and esthetic properties and, today, several products of this category are available on the market for single- appointment veneer restoration (Edelweiss Veneer by Edelweiss Dentistry, Componeer by Coltene, Visio.Lign Veneer by Bredent) [42]. The Edelweiss Veneer used for the patient in this report was the first of this “new generation” of prefabricated veneers introduced on the market in 2011. Edelweiss Veneers feature an advanced fabrication technology with heat/pressure composite curing and laser sintering and were chosen to produce the sectional veneers for the patient in this report due to their excellent performance and resistance to fatigue in laboratory testing [43]. For the purpose of diastema restoration, a prefabricated composite sectional veneer provides the same benefits of a conventional laboratory-fabricated ceramic sectional veneer (a highly esthetic restoration with no need for tooth preparation) but without many of its intrinsic limitations. First of all, the veneer’s composite resin mechanical properties allow the dentist to fabricate a less delicate restoration with a reduced risk of post-bonding crack formation on the knife-edged margins because the composite low flexural modulus yields a better absorption of the forces generated by thermal and polymerization stress [44– 46]. Another benefit of using a prefabricated composite veneer for sectional veneer fabrication and diastema restoration is the less technically demanding and time-consuming clinical procedure, involving a single appointment with a reduced number of clinical steps. A prefabricated composite veneer requires no impressions, no temporaries and no try-ons, and can be bonded like a direct composite restoration with no need for sandblasting, acid etching, post-etching cleaning or silane application. Furthermore, finishing and polishing the margins of a prefabricated composite sectional veneer are less technically demanding and time consuming than finishing and polishing the margins of a ceramic sectional veneer, since the procedure is not influenced by many variables (type of ceramic, type of polisher, polishing speed/pressure) [47,48] and can be accomplished using standard polishing systems for nanohybrid composite resin with no risk of adversely affecting the esthetic and

Dent. J. 2020, 8, 60 8 of 12 tissues and greatly contributed to the reduced post-operative discomfort and excellent acceptance by the patient.

3. Discussion This paper presents an alternative technique for minimally invasive diastema restoration with sectional veneers. The sectional veneer technique was introduced as a variation on the traditional ceramic veneer technique for highly esthetic veneer restoration with no need for tooth preparation [34,35]. However, despite the combination of excellent esthetics and no sacrifice of the tooth structure, ceramic sectional veneers have failed to enter the mainstream of general dentistry because of the technically demanding clinical procedure and the delicate laboratory fabrication process. Another limitation to the popularity of the ceramic sectional veneer technique is the high risk of accidental breakage and post-bonding crack formation on the knife-edged margins due to the reduced ceramic thickness and the unfavorable ceramic/composite thickness ratio [36–38]. In the case presented in this paper, the sectional veneer technique was reinterpreted using a prefabricated composite veneer. The prefabricated composite veneer technique was originally launched in the late 1970s (Mastique Veneer System, Caulk Dentsply) but with limited success because the large glass filler technology available at the time did not provide adequate esthetics and durability [39–41]. However, the concept of a prefabricated veneer was rejuvenated about 40 years later thanks to the introduction of contemporary composite resin with improved mechanical and esthetic properties and, today, several products of this category are available on the market for single-appointment veneer restoration (Edelweiss Veneer by Edelweiss Dentistry, Componeer by Coltene, Visio.Lign Veneer by Bredent) [42]. The Edelweiss Veneer used for the patient in this report was the first of this “new generation” of prefabricated veneers introduced on the market in 2011. Edelweiss Veneers feature an advanced fabrication technology with heat/pressure composite curing and laser sintering and were chosen to produce the sectional veneers for the patient in this report due to their excellent performance and resistance to fatigue in laboratory testing [43]. For the purpose of diastema restoration, a prefabricated composite sectional veneer provides the same benefits of a conventional laboratory-fabricated ceramic sectional veneer (a highly esthetic restoration with no need for tooth preparation) but without many of its intrinsic limitations. First of all, the veneer’s composite resin mechanical properties allow the dentist to fabricate a less delicate restoration with a reduced risk of post-bonding crack formation on the knife-edged margins because the composite low flexural modulus yields a better absorption of the forces generated by thermal and polymerization stress [44–46]. Another benefit of using a prefabricated composite veneer for sectional veneer fabrication and diastema restoration is the less technically demanding and time-consuming clinical procedure, involving a single appointment with a reduced number of clinical steps. A prefabricated composite veneer requires no impressions, no temporaries and no try-ons, and can be bonded like a direct composite restoration with no need for sandblasting, acid etching, post-etching cleaning or silane application. Furthermore, finishing and polishing the margins of a prefabricated composite sectional veneer are less technically demanding and time consuming than finishing and polishing the margins of a ceramic sectional veneer, since the procedure is not influenced by many variables (type of ceramic, type of polisher, polishing speed/pressure) [47,48] and can be accomplished using standard polishing systems for nanohybrid composite resin with no risk of adversely affecting the esthetic and mechanical properties and of initiating internal crack propagation [49,50]. On the other hand, a ceramic sectional veneer is expected to provide better longevity than a composite sectional veneer thanks to ceramic’s superior mechanical properties and color stability. In clinical studies, ceramic veneers show excellent clinical performance [51–53] and, in a recent systematic review and meta-analysis, the estimated overall cumulative survival rate of glass–ceramic and feldspathic porcelain veneers was 89% in a median follow-up period of 9 years [54]. However, at the moment, there is no clinical study reporting on the longevity of ceramic sectional veneers and it is possible that their survival rate would not be as good as conventional ceramic veneers because laboratory studies show high stress concentrations at Dent. J. 2020, 8, 60 9 of 12 the bonding interface of ceramic sectional veneers [55]. In a three-dimensional finite element analysis, ceramic sectional veneer diastema restoration shows a significantly higher stress concentration than direct composite diastema restoration and the larger the size of the diastema, the higher the von Mises stress value. Stress distribution is concentrated along the margins of the sectional veneer, leading to possible debonding or accelerated marginal degradation [56,57]. Possible clinical alternatives to the sectional veneer approach would have been orthodontic space closure with conventional [58] or miniscrew-assisted [59] orthodontic therapy. However, these choices would have been more time-consuming and would have caused aesthetic discomfort due to the presence of the appliance. Additionally, during both vestibular [60] and lingual [61] orthodontic therapies, dental hygiene procedures are more complex and oral microbiology could change. Clinical studies are available for diastema restoration made with direct composites and show acceptable clinical performance and longevity: Frease et al. scored an 84.6% survival rate at 5 years with a clinical quality rated from good to excellent for most of the diastema restorations examined [62], Peumans et al. reported an 89% survival rate at 5 years [63], Gresnigt et al. found a survival rate of 87.5% after a mean observation period of 41.3 months [44]. The prefabricated composite veneer used in this case report is expected to provide even better longevity than conventional direct composite diastema restoration because the incorporation of heat and pressure in the curing process increases the filler density and monomer conversion rate with a positive impact on physical properties and color stability [64–66]. It is as yet unknown to what extent the technology involved in the fabrication of Edelweiss prefabricated veneers effects clinical performance, since this technique was recently introduced on the market and clinical studies are not yet available. It is possible that a diastema restoration made with a traditional ceramic sectional veneer still outperforms a diastema restoration made with an Edelweiss prefabricated composite sectional veneer because of its higher mechanical strength and better resistance to aging. However, for many dentists and many patients, the gap in longevity could be compensated by the benefits of a restoration that involves a less technically demanding clinical procedure, a less time-consuming technique, possible intraoral repair and a more affordable cost for the patient.

4. Conclusions The concept of successful restoration in contemporary dentistry embraces not only the traditional criteria of minimal biological cost, good longevity and successful esthetic integration, but also other factors, including the uncomplicated technique, possible intraoral repair, reduced soft tissue trauma and affordable financial cost. It is up to the dentist to balance all these factors and select the best treatment for the patient. However, the wider the choice of treatment options, the easier for the dentist to select the best treatment based on the clinical needs and for the patient to choose the best treatment based on his esthetic expectations and financial possibilities. The technique presented in this paper implements the traditional choice of either a direct composite or indirect ceramic and introduces an additional treatment option to produce a noninvasive diastema restoration in a single appointment, with a reduced number of clinical steps.

Author Contributions: Conceptualization, C.N. and A.S.; methodology, C.N.; software, C.N.; validation, C.N. and A.S.; formal analysis, C.N. and A.S.; investigation, C.N.; resources, C.N.; data curation, C.N.; writing—original draft preparation, C.N.; writing—review and editing, A.S.; visualization, C.N. and A.S.; supervision, C.N.; project administration, C.N. and A.S.; funding acquisition, C.N. All authors have read and agreed to the published version of the manuscript. Funding: This research received no external funding. Acknowledgments: Authors would like to thank the manufacturer for providing the materials tested in the present case report. Dent. J. 2020, 8, 60 10 of 12

Conflicts of Interest: The author Claudio Novelli is a scientific consultant for Edelweiss Dentistry. No funding was provided by Edelweiss Dentistry for the completion of this study. The author Andrea Scribante has no conflicts of interest to declare. Consent: Written informed consent was obtained from the patient for publication of this case report and supplementary images.

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