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OBJECTIVE: This article provides an update on the direct-indirect composite veneer technique. CLINICAL CONSIDERATIONS: Composite veneers have long been used as a conservative and esthetic treatment option for anterior teeth. While they are generally performed using a direct technique, there has been renewed interest in the direct-indirect composite veneer technique because of its advantages and broad indications for restoration of tooth color and morphology. In the direct-indirect composite veneer technique, the selected composites are initially applied on the tooth using a layering approach, without any bonding agent, sculpted to a primary anatomic form with slight excess, and light-cured. The partially polymerized veneer is then removed from the tooth, heat-tempered, and finished to final anatomy and processed extra-orally before being luted. Advantages of this technique include enhanced physical and mechanical properties afforded by the tempering process, unrivaled marginal adaptation, enhanced finishing and polishing, and the ability to try-in the veneer before luting, enabling a shade verification and modulation process that is not possible with the direct technique. The direct-indirect approach also affords enhanced gingival health and patient comfort. CONCLUSION: This article reviews the direct-indirect composite veneer technique, and outlines critical steps and tips for clinical success. CLINICAL SIGNIFICANCE: The direct-indirect technique for composite veneers combines advantages of the direct composite placement technique with those of the indirect veneer technique, including operator control, single-visit fabrication and delivery, increased material properties, and excellent esthetics.

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In this case report, we share a conservative and simple restorative management approach for a relatively complex esthetic situation on an adult patient with an ankylosed maxillary central incisor in infra-occlusion. A 37-year-old healthy female patient presented for a consultation with a chief complaint of an unappealing smile. The intraoral exam revealed tooth #8 (FDI 11) was in obvious and significant infra-occlusion due to altered eruption. Periapical radiographs of this area were non-contributory and all teeth responded within normal limits to pulp vitality tests. After review of several treatment options, the patient opted for a conservative restorative approach in which a partial ceramic veneer was planned for the ankylosed tooth, while composite resin was used on the contralateral central incisor to achieve a symmetric and pleasant result. CLINICAL SIGNIFICANCE: A relatively complex clinical problem was satisfactorily resolved with a very conservative option in which composite resin and a ceramic veneer were used to restore an asymmetric smile.

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Marginal and internal adaptation is critical for the success of indirect restorations. New imaging systems make it possible to evaluate these parameters with precision and non-destructively. This study evaluated the marginal and internal adaptation of zirconia copings fabricated with two different systems using both silicone replica and microcomputed tomography (micro-CT) assessment methods. A metal master model, representing a preparation for an all-ceramic full crown, was digitally scanned and polycrystalline zirconia copings were fabricated with either Ceramill Zi (Amann-Girrbach) or inCoris Zi (Dentslpy-Sirona), n=10. For each coping, marginal and internal gaps were evaluated by silicone replica and micro-CT assessment methods. Four assessment points of each replica cross-section and micro-CT image were evaluated using imaging software: marginal gap (MG), axial wall (AW), axio-occlusal angle (AO) and mid-occlusal wall (MO). Data were statistically analyzed by factorial ANOVA and Tukey test (a=0.05). There was no statistically significant difference between the methods for MG and AW. For AO, there were significant differences between methods for Amann copings, while for Dentsply-Sirona copings similar values were observed. For MO, both methods presented statistically significant differences. A positive correlation was observed determined by the two assessment methods for MG values. In conclusion, the assessment method influenced the evaluation of marginal and internal adaptation of zirconia copings. Micro-CT showed lower marginal and internal gap values when compared to the silicone replica technique, although the difference was not always statistically significant. Marginal gap and axial wall assessment points showed the lower gap values, regardless of ceramic system and assessment method used.

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Abstract Marginal and internal adaptation is critical for the success of indirect restorations. New imaging systems make it possible to evaluate these parameters with precision and non-destructively. This study evaluated the marginal and internal adaptation of zirconia copings fabricated with two different systems using both silicone replica and microcomputed tomography (micro-CT) assessment methods. A metal master model, representing a preparation for an all-ceramic full crown, was digitally scanned and polycrystalline zirconia copings were fabricated with either Ceramill Zi (Amann-Girrbach) or inCoris Zi (Dentslpy-Sirona), n=10. For each coping, marginal and internal gaps were evaluated by silicone replica and micro-CT assessment methods. Four assessment points of each replica cross-section and micro-CT image were evaluated using imaging software: marginal gap (MG), axial wall (AW), axio-occlusal angle (AO) and mid-occlusal wall (MO). Data were statistically analyzed by factorial ANOVA and Tukey test (a=0.05). There was no statistically significant difference between the methods for MG and AW. For AO, there were significant differences between methods for Amann copings, while for Dentsply-Sirona copings similar values were observed. For MO, both methods presented statistically significant differences. A positive correlation was observed determined by the two assessment methods for MG values. In conclusion, the assessment method influenced the evaluation of marginal and internal adaptation of zirconia copings. Micro-CT showed lower marginal and internal gap values when compared to the silicone replica technique, although the difference was not always statistically significant. Marginal gap and axial wall assessment points showed the lower gap values, regardless of ceramic system and assessment method used.

Resumo A adaptação marginal e interna é fundamental para o sucesso das restaurações indiretas e novos sistemas de imagem permitem avaliar esses parâmetros de maneira não-destrutiva e com precisão. Este estudo avaliou a adaptação marginal e interna de copings de zircônia fabricados com dois sistemas diferentes, utilizando as técnicas da réplica em silicone e micro-CT. Um modelo-mestre de metal, representando um preparo para uma coroa totalmente cerâmica foi digitalizado e copings de zirconia policristalina (Ceramill Zi, Amann Girrbach e inCoris Zi, Dentslpy Sirona, n=10) foram fabricados. Para cada coping, a adaptação marginal e interna foi avaliada pelas técnicas da réplica em silicone e micro-CT. Foram avaliados quatro pontos de cada seção transversal e imagem de micro-CT: adaptação marginal (MG), parede axial (AW), ângulo axial-oclusal (AO) e parede centro-oclusal (MO) utilizando um software de imagem. Os dados foram analisados estatisticamente por ANOVA e teste de Tukey (a=0,05). Não houve diferença estatisticamente significativa entre as duas técnicas para MG e AW. Para AO, houve diferenças significativas entre as técnicas para copings da Amann, enquanto que para copings da Dentsply Sirona foram observados valores semelhantes. Para o MO, ambas as técnicas apresentaram diferenças estatisticamente significativas. Observou-se uma correlação positiva entre os valores de adaptação determinados pelas duas técnicas. O método de avaliação influenciou a avaliação da adaptação marginal e interna de copings de zircônia. Pode-se concluir que a micro-CT mostrou menores valores de adaptação marginal e interna quando comparado com a técnica de réplica em silicone. Os pontos de avaliação da margem e da parede axial mostraram os menores valores de adaptação, independente do sistema cerâmico e da técnica de avaliação utilizados.

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PURPOSE: To evaluate the presence and length of microcracks in resin-based materials finished with different techniques, using optical coherence tomography (OCT). METHODS: Standardized Class V preparations (3x2x2mm) were made in the facial and lingual surfaces of 20 recently-extracted human third molars. 20 preparations were restored with a resin-based composite material (RBC; Filtek Supreme Ultra) and the other 20 with a resin-modified glass-ionomer material (RMGI; Ketac Nano). After final polymerization, specimens were further stratified by finishing system: aluminum oxide discs (Sof-Lex) or spiral fluted carbide bur series (H48L). By random allocation, each extracted tooth therefore received one RBC and one RMGI restoration, and equal numbers of restorations from each material were finished using each finishing system (n= 10). After 24 hours of storage in 100% humidity at room temperature, the specimens were evaluated at x20 to x600 under environmental SEM. Cross-sectional occlusal-cervical B-mode images were obtained in increments of 25 mm from the mesial margin to the distal margin of the restoration using a spectral-domain (SD) OCT system and analyzed using Image J software to identify and measure microcrack penetration into each restoration. The total length (mm) at the point of the deepest microcrack penetration in each specimen was recorded. Data were statistically analyzed using a t-test. RESULTS: No microcracks were observed in the RBC samples. However, microcrack presence was identified in all of the RMGI specimens. The t-test showed a statistically significant difference (P< 0.05) in mean microcrack length values based on the finishing technique used for the RMGI samples. [SofLex: 0.67 (± 0.28) mm; carbide: 1.26 (± 0.30)] mm. Two-way ANOVA showed significant differences in the factors "finishing technique" and "restorative material" (P< 0.001). The interaction of these two factors was also statistically significant (P< 0.001). For the tested RMGI, Tukey post-hoc test revealed that the finishing with aluminum oxide groups resulted in statistically significant lower mean microcrack length when compared to spiral fluted carbide burs (P< 0.001). CLINICAL SIGNIFICANCE: Resin-modified glass-ionomer (RMGI) is more susceptible to microcrack presence than resin-based composites. Also, aluminum oxide discs produced lower values of mean microcrack length than spiral fluted carbide burs after the finishing procedure of RMGI restorations.

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PURPOSE: The purpose of this study was to report the prevalence of carious and non-carious cervical lesions in the teeth of five archaeological populations. A secondary purpose was to report the association between age, gender, diet, tooth wear, carious cervical lesions, and non-carious cervical lesions. MATERIALS AND METHODS: One hundred and four archaeological specimens from subjects originating from five distinct geographical areas were examined to detect the presence of carious cervical lesions, non-carious cervical lesions, and tooth wear. Data were tabulated and statistics used to describe prevalence and non-causal associations. RESULTS: Carious cervical lesions were prevalent in all populations except among Labradoreans, while non-carious cervical lesions were found predominantly in Mexicans. The authors found no association between non-carious cervical lesions and age, gender, and diet in any of the populations. Tooth wear was noted in all populations, but the highest rates of severe wear were noted among the Labradoreans and New Mexicans. Age was associated with tooth wear in all populations except Ohioans. There was no association between tooth wear and non-carious cervical lesions. CONCLUSIONS: The prevalence of carious cervical lesions among the five archaeological populations studied ranged from 0 to 65%. Non-carious cervical lesions were not prevalent among these populations, being found predominantly in Mexicans (26%). CLINICAL SIGNIFICANCE Historically, carious and non-carious cervical lesions can be found in individuals with no access to modern oral hygiene tools. The findings of this study are not conclusive, however, as the associations described are not causal. (J Esthet Restor Dent 21:324-335, 2009).

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O tratamento clareador caseiro consiste na utilização de um gel á base de peróxido de carbamina, o qual permanece em íntimo contato com os tecidos bucais por certo período, diariamente, durante alguns dias ou semanas. Ao longo do clareamento, os processos de des/remineralização podem ocorrer na estrutura dental, alterando o conteúdo mineral do esmalte e da dentina. Neste artigo, revisam-se estudos que descrevem o processo dinâmico do clareamento, outros que discutem os efeitos do clareamento no equilíbrio mineral do dente e os possíveis fatores que levam às alterações no conteúdo mineral. A partir desses artigos, verifica-se que não existem ainda evidências que comprovem o efeito permanente do tratamento clareador sobre o equilíbrio mineral das estruturas dentais. Fortes evidências sugerem que fatores protetores, principalmente os componentes salivares, previnem perda mineral significativa e restabelecem o conteúdo mineral durante e após o tratamento clareador. Para favorecer a remineralização e minimizar a desmineralização durante o clareamento, a escolha do agente clareador parece ser de extrema importância. Nas características esperadas de agentes clareadores caseiros pode-se incluir o pH neutro e a presença de flúor e devem-se evitar altas concentrações de peróxido.

Home bleaching requires that a peroxide-based bleaching gel be in contact with intraoral tissues for a number of hours a day for several days. Throughout bleaching treatment, demineralization and remineralization events likely occur at the dental structure, affecting the tooth mineral content. Studies considering the bleaching dynamic process were reviewed and attention was given to those that discuss the effects of the treatment on the dental mineral equilibrium and the conditions that lead to alteration of the mineral content. There is no definitive conclusion whether home bleaching affects permanently or not dental mineral equilibrium. Strong evidence suggests that protective factors mainly salivary components prevent significant mineral loss and/or restore mineral content during and after bleaching treatment. To favor remineralization and minimize demineralization during bleaching, the choice of bleaching agent is important. Ideal characteristics of home bleaching agents include neutral pH and fluoride content. Furthermore, high concentrations of peroxide should be avoided.

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PURPOSE: This study evaluated bond strengths of orthodontic brackets to instrumented and uninstrumented enamel using self-etching adhesive systems when compared to a total-etch adhesive system. The adhesive remnant index (ARI) was also determined after debonding. METHODS: 140 bovine incisors were included in acrylic resin, and divided randomly in two groups: instrumented vs. uninstrumented enamel. For the instrumented enamel, specimens had their facial enamel ground flat to 600-grit. In each group, specimens were subdivided into four experimental subgroups according to the adhesive technique used: Transbond Plus, Adper Prompt L-Pop, iBond, and Adper Single Bond, applied following manufacturers' instructions. Orthodontic brackets were bonded to the treated instrumented or uninstrumented enamel with Transbond XT light-cured resin-based composite cement, and the bond strength was tested in shear mode after 7 days. One group where no etch and no adhesive were used served as a control. ARI scores were determined after debonding. RESULTS: There was no statistically significant difference in mean bond strengths between instrumented and uninstrumented enamel for any of the adhesive systems (P > or = 0.05). No significant differences were observed for bond strengths among the adhesives tested (P = 0.308), and all experimental groups resulted in mean bond strengths significantly higher than the controls (P < 0.05). Statistically significant differences were identified when ARI scores were compared, with less adhesive remnants being observed for iBond (uninstrumented enamel) and the control groups (P < 0.05).

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Composites are widely used for the functional and esthetic restorations of anterior teeth. The placement of a cavosurface margin bevel on the enamel margins of anterior composite preparations traditionally has been recommended to enhance retention and for esthetic reasons, as bevels result in a gradual transition between the restoration and the tooth. However, advances in adhesive and composite technology, as well as careful composite selection and application techniques, have made it possible to place adequate anterior composites without a bevel. Elimination of bevels results in more conservative cavity preparations, a simpler technique, a reduced restored surface area, and the preservation of tooth structure when the restoration is replaced. This Critical Appraisal summarizes clinical reviews and laboratory publications related to the influence of cavity preparation and, more specifically, cavosurface bevels on the performance of anterior composite restorations.

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UNLABELLED: Reproducing the form, function, and optical characteristics of natural dental structures with direct composites in large and moderately large proximoincisal (Class IV) restorations represents a great challenge for clinicians in general. Understanding color is fundamental to achieving success when restoring these defects, as was discussed in Part I of this two-part article (Volume, 16, Number 6). The proper restoration of the functional lingual contour is also a challenge that cannot be overcome without close attention to the restorative technique. In this second article, the composite application technique is discussed and presented in detail. Clinical photographs illustrate the proposed technique. CLINICAL SIGNIFICANCE: The proposed clinical protocol, including a try-in of the shades in a mock-up restoration to more accurately define color and shape, and a silicone guide to transfer the lingual and proximoincisal contour of the mock-up to the final restoration, is of great help to successfully restore proximoincisal defects.

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