CLINICAL REPORT

aClinical AssobAssistant Pr

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Conservative treatment planning in veneer replacement

Sandra Guzmán-Armstrong, DDS, MSa and Rodrigo Rocha Maia, DDS, MS, PhDb

ABSTRACTThis clinical report describes a conservative treatment in veneer replacement where diastemas,malalignment, and midline shift were the main modifying factors. When replacement veneers areindicated, the definitive results can only be accurately predicted after an esthetic reanalysis of theexisting restorations. (J Prosthet Dent 2016;115:393-396)

The presence of a diastemabetween the anterior teeth canbe esthetically challengingbecause it may distort apleasing smile.1 While severaltreatment options for diastema

closure can be presented to the patient, a carefullydeveloped diagnosis is necessary to formulate the mostconservative and predictable treatment plan. Providingminimally invasive treatment and understanding the bestoptions for tooth preservation are important aspects ofthe prognosis. A systematic esthetic analysis thatprogresses from facial to dentofacial to dentogingival andfinally to dental analysis is needed for a successfulesthetic outcome.2 Often patients seek treatment inearly adulthood, limiting the options for conservativelyreplacing their restorations later in life. This is particularlytrue if the previous treatment goal was not accomplishedthrough a minimally invasive approach. The purpose ofthis clinical report was to present the clinical parametersthat are essential to conservative treatment planning forveneer replacement.

CLINICAL REPORT

A 49-year-old woman presented to the operative dentistryclinic with a noncontributory medical history. The patientwas determined to be at low caries risk with excellent oralhygiene and had a history of routine dental care. The pa-tient was chiefly concerned about the color and marginalstaining of her anterior restorations and the uneven shapeof her maxillary anterior teeth, as seen in Figure 1A, B.

Oral evaluation revealed marginal stained ceramicveneers from themaxillary right canine to the leftmaxillary

ciate Professor, Operative Dentistry Department, The University of Iowa Cofessor, Operative Dentistry Department, The University of Iowa College of

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first premolar, an impacted maxillary left canine, metalceramic crowns on the maxillary left and right first molarsand mandibular right first molar, amalgam restorations inthe maxillary and mandibular right and left first molars,and composite resin restorations in the maxillary andmandibular left and right first premolars. No active orrecurrent caries lesions were found. Diastemas were pre-sent between the maxillary incisors (Fig. 1C). A completemouth series of radiographs was made. The periodontalexamination showed no gingival inflammation, no prob-ing depths, and mild gingival recession on the maxillaryanterior teeth.

On the basis of an analysis of the relationship betweenthe interpupillary, intercommisural, and incisal lines,canting of the maxillary anterior teeth was determined.The central incisors were disproportional, and the dentalmidline was shifted 3 mm to the left because of theimpacted maxillary left canine. After an evaluation of thebuccal corridor width, the restoration of the maxillary rightand left premolars with ceramic veneers was deemedessential in order to provide a broader, more estheticsmile. According to Moore et al,3 fullness of the smile is animportant feature in determining smile attractiveness.

The patient presented with a Class I right canine andmolar relationship and a Class II left premolar (due toimpacted canine) and molar relationship, 3 mm hori-zontal overlap, and 4 mm vertical overlap. Minimalposterior wear was observed. Muscle palpation revealed

ollege of Dentistry and Dental Clinics, Iowa City, Iowa.Dentistry and Dental Clinics, Iowa City, Iowa.

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Figure 1. Preoperative photographs. A, Smile. B, Frontal view. C, Maxil-lary occlusal view.

Figure 2. Trial restorations with bis-acrylic interim material (Protemp; 3MESPE) to evaluate esthetics, function, and phonetics.

Figure 3. Minimal definitive preparation for ceramic veneers onmaxillary anterior teeth.

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no tenderness, and joint examination revealed no crep-itus or abnormality on opening or lateral excursivemovement. She exposed 75% to 80% of her maxillaryanterior teeth and 2 to 3 mm of tooth structure with herlip in resting position. Both her lip mobility and lip lengthwere average, and the gingival margins were notrevealed. The patient had a wide smile showing thebuccal corridor on both sides.

After prophylaxis, home tooth-whitening treatmentwas completed with 10% carbamide peroxide (Opales-cence 10%; Ultradent Products Inc).4 Extraoral and

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intraoral photographs were made for esthetic analysis. ADigital Smile Design (DSD) analysis was completed todetermine ideal tooth shape and proportion in relation-ship to the available space.5 Diagnostic casts were madeand mounted in an articulator (Stratos 300; IvoclarVivadent AG). A diagnostic waxing was completed toestablish the most acceptable proportions of the maxillaryanterior teeth, given the limitations of maxillary anteriortooth position and the impacted canine. The existingceramic veneers were removed, avoiding additionalpreparation of the tooth structure. A silicone replica ofthe diagnostic waxing was made, and diagnostic resto-rations were placed with bis-acrylic interim materialshade B1 (Protemp; 3M ESPE). The diagnostic restora-tions were used to evaluate esthetics, function, andphonetics and to provide a guideline for preparing thetooth structure. A complete evaluation of the desiredtooth position and alignment was accomplished (Fig. 2).The tooth proportion of the maxillary centrals wasestablished at 75% to 85% to compensate for themaxillary midline shift to the left (2 to 3 mm). According

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Figure 4. Cementing definitive ceramic veneers with dual-polymerizingadhesive system and resin cement.

Figure 5. Postoperative photographs. A, Smile. B, Frontal view. C,Maxillary occlusal view.

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to Chu et al,6 the width of a maxillary lateral incisorshould be approximately 2 mm less than the centralincisor. The width of the canine was established as 1 mmless than the central incisor. The vertical position of themaxillary teeth was evaluated to determine the appro-priateness of the incisal edge position and its relationshipwith the border of the lower lip both at rest anddynamically, the distance between the upper and lowerlip, and appropriate phonetics. According to Spear,7 themaxillary incisal edge position can be reestablishedprimarily on the basis of esthetic concerns; however,in many instances, this is a subjective endeavor. Asthere is a range within which the incisal length may beestablished, the functional requirements of the incisors asthe anterior determinant of occlusal function must not beoverlooked.

Occlusal evaluation was taken into consideration, andthe patient’s horizontal and vertical overlap of 1 to 2 mmwas reduced by decreasing the thickness of the ceramicveneers and establishing an improved width-length ratio.To make sure the occlusal forces were not directed at therestorative-tooth junction, the incisal-edge position wastaken as the terminal point and the occlusal contact asthe starting point during the intermediate pathway ofmovement.8

The gingival architecture of the anterior segment didnot need to be modified because of the lack of gingivalexposure during smiling and a gingival discrepancy lessthan 1.5 mm.9 After the cervical margins were prepared,it was determined that the zenith and gingival heightswere well balanced, providing adequate gingival har-mony. The papilla formation in the presence of a dia-stema often results in blunting of the interdental papilla.One of the challenges of closing a diastema is not toleave an excessively wide gingival embrasure, oftenreferred to as a black triangle.10 Because the patient’sprevious restorations resulted in a distance of 6 mm fromthe base of the contact point to the crest of the bone, the

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papilla was partially present. The design and location ofthe contact point is the key requirement in avoiding blacktriangles; therefore, the contact of the restoration wasplaced closer to the gingival tissue (5 mm) from thecontact point to the crest of the bone.11 In addition,studies have shown that the papilla proportion formaxillary anterior teeth, as measured from the gingivalzenith to the papilla crest, is approximately 40% of thetotal length of the clinical crown. This was also replicatedin the definitive restorations.

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The trial and interim restorations replicated thedesired contours and position of the definitive veneers.Because all the parameters had been established inadvance, preparation of the teeth through the interimrestorations progressed as though preparing teeth inoptimal alignment.12 As seen in Figure 3, a minimalpreparation for ceramic veneers was completed, and theinterproximal areas were then refined. After the definitiveimpression had been made with a polyvinyl siloxanematerial (Aquasil; Dentsply Intl), the interim restorationswere fabricated. Ceramic veneers were made from alithium disilicate material (IPS e.max; Ivoclar VivadentAG) and cemented with a dual-polymerizing adhesivesystem (All Bond 3; Bisco Inc) and resin cement (Calibra;Dentsply Caulk) (Fig. 4).13 The completed restorationsare shown in Figure 5.

DISCUSSION

In the presence of diastemas and/or malalignment of theanterior teeth, orthodontic correction can be the mostconservative treatment option. Sometimes restorativeand periodontal procedures are necessary after ortho-dontics to provide the optimal outcome. Treatmentplans should not be selected empirically but should bebased on thorough documentation, measurements,casts, and photographs as part of adequate treatmentplanning. As illustrated for this patient, a completeevaluation of the treatment plan and prognosis couldonly be finalized after the existing ceramic veneers hadbeen removed to evaluate the location and inclination ofthe teeth. The patient must understand that a morepredictable evaluation of the definitive results can onlybe completed after removal of existing restorations andan esthetic analysis.

For this patient, after the removal of the restorations,complete crowns were deemed unnecessary. The patientalso understood that she had to accept a compromisedmidline shift to avoid more invasive preparation of herteeth, including possible crowns and/or orthodontictreatment.

CONCLUSION

Many methods of treating anterior diastemas have beendocumented.14 Regardless of the treatment chosen, thepatient should be aware that when replacement of

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ceramic veneers is necessary, previous restorations mustbe removed for a more accurate esthetic analysis andmore predictable results for the definitive treatmentplan.

REFERENCES

1. Gurel G. Porcelain laminate veneers for diastema closure. In: The science andart of Porcelain Laminate Veneers. Quintessence Publishing Co Inc. Ergo-lding, Germany, 2003. p. 369-92.

2. Oquendo A, Brea L, David S. Diastema: correction of excessive spaces in theesthetic zone. Dent Clin North Am 2011;55:265-8.

3. Moore T, Southard KA, Casko JS, Qian F, Southard TE. Buccal cor-ridors and smile esthetics. Am J Orthod Dentofacial Orthop 2005;127:208-13.

4. Prevedello GC, Vieira M, Furuse AY, Correr GM, Gonzaga CC. Estheticrehabilitation of anterior discolored teeth with lithium disilicate all-ceramicrestorations. Gen Dent 2012;60:274-8.

5. Coachman C, Calamita M. Digital Smile Design: a tool for treatment plan-ning and communication in esthetic dentistry. Quintessence Dent Technol2012;35:103-11.

6. Chu S, Tarnow D, Bloom M. Diagnosis, etiology. In: Tarnow D, Chu S, Kim J,editors. Aesthetic restorative dentistry: principles and practice. Mahwah:Montage Media; 2008. p. 1-25.

7. Spear FM. The maxillary central incisor edge: a key to esthetic andfunctional treatment planning. Compend Contin Educ Dent 1999;20:512-6.

8. Gracis S, Chu S. The anterior and posterior determinants of occlusion andtheir relationship to aesthetic restorative dentistry. In: Tarnow D, Chu S,Kim J, editors. Aesthetic restorative dentistry: principles and practice. Mah-wah: Montage Media; 2008. p. 65-97.

9. Kokich VO Jr, Kokich VG, Kiyak HA. Comparing the perception ofdentists and lay people to altered dental esthetics: asymmetric andsymmetric situations. Am J Orthod Dentofacial Orthop 2006;130:141-51.

10. De Araujo EM Jr, Fortkamp S, Baratieri LN. Closure of diastema and gingivalrecontouring using direct adhesive restorations: a case report. J Esthet RestorDent 2009;21:229-40.

11. Tarnow DP, Magner AW, Fletcher P. The effect of the distance from thecontact point to the crest of bone on the presence or absence of the inter-proximal dental papilla. J Periodontol 1992;63:995-6.

12. Gurel G. Predictable and precise tooth preparation techniques forporcelain laminate veneers in complex cases. Int Dent SA 2007;9:30-40.

13. Powers JM, Farah JW. Ceramic adhesives: cementing vs bonding. Inside Dent2010;6:70-2.

14. Beasley WK, Maskeroni AJ, Moon MG, Keating GV, Maxwell AW. The or-thodontic and restorative treatment of a large diastema: a case report. GenDent 2004;52:37-41.

Corresponding author:Dr Sandra Guzmán-ArmstrongThe University of Iowa College of Dentistry and Dental ClinicsS246 DSB-801 Newton RdIowa City, IA 52240Email: sandra-guzman-armstrong@uiowa.edu

AcknowledgmentsThe authors thank Joyce Francois (dental assistant), Uri Yarovesky, and the stafffrom Opus One Dental Laboratory (Agoura Hills, Calif) for their valuablecontributions.

Copyright © 2016 by the Editorial Council for The Journal of Prosthetic Dentistry.

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