Emergence profile customization technique during implant transfer.

This case report aimed to describe the clinical considerations in oral rehabilitation with prostheses on implants in the anterior region, using emergence profile customization technique during implant transfer. A patient presented with a missing left upper central incisor and with not satisfactory esthetic in the other upper incisors. After diagnosis, a treatment plan was elaborated: implant placement in this region; ceramic laminates for teeth 11 and 22, and full crown for tooth 12. During the impression procedure, the implant transfer was customized by copying the gingival profile. The prostheses were made using IPS e.max ceramic system and luted with resin cement. The patient was submitted to annual follow-up examinations that did not show any irregularity or deficiency in the prostheses. The technique performed is a viable alternative that can be used in oral rehabilitation with implants involving anterior teeth because it allows a predictable level of adaptation.

Stress distribution in delayed replanted teeth splinted with different orthodontic wires: a three-dimensional finite element analysis.

AIM: The aim was to evaluate the biomechanical behavior of the supporting bony structures of replanted teeth and the periodontal ligament (PDL) of adjacent teeth when orthodontic wires with different mechanical properties are applied, with three-dimensional finite element analysis. MATERIALS AND METHODS: Based on tomographic and microtomographic data, a three-dimensional model of the anterior maxilla with the corresponding teeth (tooth 13-tooth 23) was generated to simulate avulsion and replantation of the tooth 21. The teeth were splinted with orthodontic wire (Ø 0.8 mm) and composite resin. The elastic modulus of the three orthodontic wires used, that is, steel wire (FA), titanium-molybdenum wire (FTM), and nitinol wire (FN) were 200 GPa, 84 GPa, and 52 GPa, respectively. An oblique load (100 N) was applied at an angle of 45° on the incisal edge of the replanted tooth and was analyzed using Ansys Workbench software. The maximum (σmax) and minimum (σmin) principal stresses generated in the PDL, cortical and alveolar bones, and the modified von Mises (σvM) values for the orthodontic wires were obtained. RESULTS: With regard to the cortical bone and PDL, the highest σmin and σmax values for FTM, FN, and FA were checked. With regard to the alveolar bone, σmax and σmin values were highest for FA, followed by FTM and FN. The σvM values of the orthodontic wires followed the order of rigidity of the alloys, that is, FA > FTM > FN. CONCLUSION: The biomechanical behavior of the analyzed structures with regard to all the three patterns of flexibility was similar.

Influence of platform and abutment angulation on peri-implant bone. A three-dimensional finite element stress analysis.

The aim of this study was to evaluate stress distribution on the peri-implant bone, simulating the influence of Nobel Select implants with straight or angulated abutments on regular and switching platform in the anterior maxilla, by means of 3-dimensional finite element analysis. Four mathematical models of a central incisor supported by external hexagon implant (13 mm × 5 mm) were created varying the platform (R, regular or S, switching) and the abutments (S, straight or A, angulated 15°). The models were created by using Mimics 13 and Solid Works 2010 software programs. The numerical analysis was performed using ANSYS Workbench 10.0. Oblique forces (100 N) were applied to the palatine surface of the central incisor. The bone/implant interface was considered perfectly integrated. Maximum (σmax) and minimum (σmin) principal stress values were obtained. For the cortical bone the highest stress values (σmax) were observed in the RA (regular platform and angulated abutment, 51 MPa), followed by SA (platform switching and angulated abutment, 44.8 MPa), RS (regular platform and straight abutment, 38.6 MPa) and SS (platform switching and straight abutment, 36.5 MPa). For the trabecular bone, the highest stress values (σmax) were observed in the RA (6.55 MPa), followed by RS (5.88 MPa), SA (5.60 MPa), and SS (4.82 MPa). The regular platform generated higher stress in the cervical periimplant region on the cortical and trabecular bone than the platform switching, irrespective of the abutment used (straight or angulated).

Straight and angulated abutments in platform switching: influence of loading on bone stress by three-dimensional finite element analysis.

PURPOSE: In view of reports in the literature on the benefits achieved with the use of platform switching, described as the use of an implant with a larger diameter than the abutment diameter, the goal being to prevent the (previously) normal bone loss down to the first thread that occurs around most implants, thus enhancing soft tissue aesthetics and stability and the need for implant inclination due to bone anatomy in some cases, the aim of this study was to evaluate bone stress distribution on peri-implant bone, by using three-dimensional finite element analysis to simulate the influence of implants with different abutment angulations (0 and 15 degrees) in platform switching. METHODS: Four mathematical models of an implant-supported central incisor were created with varying abutment angulations: straight abutment (S1 and S2) and angulated abutment at 15 degrees (A1 and A2), submitted to 2 loading conditions (100 N): S1 and A1-oblique loading (45 degrees) and S2 and A2-axial loading, parallel to the long axis of the implant. Maximum (σmax) and minimum (σmin) principal stress values were obtained for cortical and trabecular bone. RESULTS: Models S1 and A1 showed higher σmax in cortical and trabecular bone when compared with S2 and A2. The highest σmax values (in MPa) in the cortical bone were found in S1 (28.5), followed by A1 (25.7), S2 (11.6), and A2 (5.15). For the trabecular bone, the highest σmax values were found in S1 (7.53), followed by A1 (2.87), S2 (2.85), and A2 (1.47). CONCLUSIONS: Implants with straight abutments generated the highest stress values in bone. In addition, this effect was potentiated when the load was applied obliquely.

Influence of resin cement thickness and temperature variation on mechanical behavior of dental ceramic fragment restoration.

To evaluate the stress behavior of ceramic fragment restoration, varying the thickness of the cement layer and intraoral temperature variation. A solid model of a upper lateral incisor was obtained and a defect at enamel distal/incisal edge was restored with a ceramic fragment. Based on this initial model, 4 different models (M) were built: M1 - absence of cement layer (CL) (0 µm of thickness); M2 - CL with an uniform thickness of 50 µm; M3 - CL with 50 µm at the margin of ceramics and 100 µm in the inner area far from margins; M4 - CL with 50 µm at the margin of ceramics and 200 µm in the inner area far from margins. The environment temperature changed from 5 °C to 50 °C in 4 increments. The finite element analysis was performed. Increase the cement layer thickness generated higher stress levels on ceramic surface in all temperatures, as well as on cement interface. In general hot temperature was the worst scenario for ceramic fragments integrity, since tensile and compressive stress were more intense. The maximum principal stress on ceramic fragment was found 90 MPa for M4 at 50 °C, followed for M3 (87 Mpa). For CL, the peak of stress was found for M3 at 5 °C (47 MPa). Is it possible to conclude that thick resin cement layer contribute to higher stress concentration on ceramic fragment, and extremely hot temperatures increase the risk of structural failure, since both ceramic and \cl are exposed to higher compressive and tensile stresses.

Poly (lactide-co-glycolide) (PLGA) Scaffold Induces Short-term Nerve Regeneration and Functional Recovery Following Sciatic Nerve Transection in Rats.

Peripheral nerve injury is an important cause of incapability and has limited available treatment. Autologous donor nerve implant is the golden standard treatment, however, may cause secondary deficits. Stem cells show positive results in preclinical settings, preserving tissue and function. We tested the efficacy of stem cells derived from human exfoliated deciduous teeth seeded in poly (lactide-co-glycolide) scaffolds in sciatic nerve transection model. Seventy-two adult male Wistar rats had 7-mm nerve gap bridge using scaffolds with (or without) stem cells. Animals were randomly divided into: sham-operated; sham-operated without scaffold; sham-operated + scaffold + stem cells; sciatic transection + no treatment; sciatic transection + acellular scaffolds; sciatic transection + scaffold + stem cells. Sciatic Functional Index and Ladder Rung Walking tests were performed before (-1), 14 and 28 days after surgery. Morphometric nerve measurement and muscle weights were assessed. Scaffolds with stem cells improved function in Sciatic Functional Index. Acellular scaffold was effective, promoting functional recovery and nerve regeneration following nerve injury. Scaffolds provide better nerve regeneration and functional recovery after sciatic transection. Despite cell therapy promoting faster recovery after sciatic transection in the Sciatic Index Score, stem cells did not improve functional and morphological recovery after nerve injury. This is the first study testing the potential use of scaffolds combined with stem cells in the early stages after injury. Scaffolds with stem cells could accelerate nerve recovery and favor adjuvant therapies, evidencing the need for further studies to increase the knowledge about stem cells' mechanisms.

Zirconia-based dental crown to support a removable partial denture: a three-dimensional finite element analysis using contact elements and micro-CT data.

Veneer fracture is the most common complication in zirconia-based restorations. The aim of this study was to evaluate the mechanical behavior of a zirconia-based crown in a lower canine tooth supporting removable partial denture (RPD) prosthesis, varying the bond quality of the veneer/coping interface. Microtomography (µCT) data of an extracted left lower canine were used to build the finite element model (M) varying the core material (gold core - MAu; zirconia core - MZi) and the quality of the veneer/core interface (complete bonded - MZi; incomplete bonded - MZi-NL). The incomplete bonding condition was only applied for zirconia coping by using contact elements (Target/Contact) with 0.3 frictional coefficients. Stress fields were obtained using Ansys Workbench 10.0. The loading condition (L = 1 N) was vertically applied at the base of the RPD prosthesis metallic support towards the dental apex. Maximum principal (σmax) and von Mises equivalent (σvM) stresses were obtained. The σmax (MPa) for the bonded condition was similar between gold and zirconia cores (MAu, 0.42; MZi, 0.40). The incomplete bonded condition (MZi-NL) raised σmax in the veneer up to 800% (3.23 MPa) in contrast to the bonded condition. The peak of σvM increased up to 270% in the MZi-NL. The incomplete bond condition increasing the stress in the veneer/zirconia interface.

Effect of long-term storage on nanomechanical and morphological properties of dentin-adhesive interfaces.

INTRODUCTION: To evaluate the influence of storage time on the elastic modulus, micromorphology, nanoleakage, and micromechanical behavior of the dentin-adhesive interfaces of five adhesive systems (Scotchbond Multi-Purpose, Clearfil SE Bond, One Up Bond F, Adper Easy One, and Filtek LS Adhesive) after 24h (T0) and 12 months (T1). METHODS: Fifty teeth were restored and distributed according to each adhesive system (n=10). At least four specimens were obtained from each tooth. One specimen was evaluated under SEM to obtain the micromorphology of dentin-adhesive interface (DAI). Two specimens were used to assess nanoleakage, one tested in T0 and the other in T1. The last specimen was used for nanoindentation, in T0 and T1, to obtain the initial and final mechanical properties of DAI structures. Two non-restored teeth were evaluated under SEM to obtain the dentin morphology. Laboratorial data were used to build 15 finite element models to assess the maximum principal stress in each time of analysis. RESULTS: Storage resulted in hydrolysis of the dentin-adhesive interfaces for all groups. Silver impregnation increased for all groups after 1 year storage (p<.05), except for Clearfil SE Bond. In general, a decrease in elastic modulus values was observed for all groups from T0 to T1 (p<.05), mainly at the hybrid layer. The FEAs showed higher stress levels at T1 than T0 simulations for all adhesives. CONCLUSION: At T1, degradation occurred at the dentin-adhesive interface formed by all adhesives, and the intensity of degradation differed depending on the type of adhesive system used. The interface formed by the self-etching primer containing the 10-MDP functional monomer showed the highest stability among the adhesive systems after 12 months of storage.

Bonding all-ceramic restorations with two resins cement techniques: a clinical report of three-year follow-up.

Ceramics have been widely used for esthetic and functional improvements. The resin cement is the material of choice for bonding ceramics to dental substrate and it can also dictate the final esthetic appearance and strength of the restoration. The correct use of the wide spectrum of resin luting agents available depends on the dental tooth substrate. This article presents three-year clinical results of a 41 years old female patient B.H.C complaining about her unattractive smile. Two all-ceramic crowns and two laminates veneers were placed in the maxillary incisors and cemented with a self-adhesive resin luting cement and conventional resin luting cement, respectively. After a three-year follow-up, the restorations and cement/teeth interface were clinically perfect with no chipping, fractures or discoloration. Proper use of different resin luting cements shows clinical appropriate behavior after a three-year follow-up. Self-adhesive resin luting cement may be used for cementing all-ceramic crowns with high predictability of success, mainly if there is a large dentin surface available for bonding and no enamel at the finish line. Otherwise, conventional resin luting agent should be used for achieving an adequate bonding strength to enamel.

Influence of voids in the hybrid layer based on self-etching adhesive systems: a 3-D FE analysis.

UNLABELLED: The presence of porosities at the dentin/adhesive interface has been observed with the use of new generation dentin bonding systems. These porosities tend to contradict the concept that etching and hybridization processes occur equally and simultaneously. Therefore, the aim of this study was to evaluate the micromechanical behavior of the hybrid layer (HL) with voids based on a self-etching adhesive system using 3-D finite element (FE) analysis. MATERIAL AND METHODS: Three FE models (Mr) were built: Mr, dentin specimen (41x41x82 µm) with a regular and perfect (i.e. pore-free) HL based on a self-etching adhesive system, restored with composite resin; Mp, similar to M, but containing 25% (v/v) voids in the HL; Mpp, similar to Mr, but containing 50% (v/v) voids in the HL. A tensile load (0.03N) was applied on top of the composite resin. The stress field was obtained by using Ansys Workbench 10.0. The nodes of the base of the specimen were constrained in the x, y and z axes. The maximum principal stress (σmax) was obtained for all structures at the dentin/adhesive interface. RESULTS: The Mpp showed the highest peak of σmax in the HL (32.2 MPa), followed by Mp (30 MPa) and Mr (28.4 MPa). The stress concentration in the peritubular dentin was high in all models (120 MPa). All other structures positioned far from voids showed similar increase of stress. CONCLUSION: Voids incorporated into the HL raised the σmax in this region by 13.5%. This behavior might be responsible for lower bond strengths of self-etching and single-bottle adhesives, as reported in the literature.

Análise do comportamento da cor de restaurações cerâmicas sem metal avaliadas por diferentes métodos: estudo clínico prospectivo / Color behavior of ceramic metal free restorations evaluated by different methods; prospective clinical study

Introdução: O processo de interpretação da cor em restaurações cerâmicas delgadas pré e pós-tratamento é um desafio. Os métodos de avaliação dos resultados são diversos e a literatura não é clara em apontar o mais eficaz e eficiente. A questão é ainda mais relevante diante da variação do cimento resinoso utilizado. Proposição: Após variar o tipo de cimento resinoso utilizado, o objetivo deste estudo foi avaliar o comportamento da cor de restaurações cerâmicas em dentes com demanda estética, ao longo de 1 ano após o tratamento, com o auxílio de diferentes métodos de acompanhamento (espectrofotômetro, fotografias, vídeos e avaliação clínica) em um estudo clínico longitudinal e prospectivo. Materiais e Métodos: Foram selecionados 28 pacientes, perfazendo um total de 204 dentes restaurados (89 facetas laminadas, 57 coroas totais ou parciais e 58 lentes de contato). 76 restaurações foram cimentadas com Rely X veneer, 71 com Variolink veneer e 57 com Rely X U200. Foram realizadas mensurações de cor com espectrofotômetro, fotografias digitais e vídeos gravados no decorrer do tratamento e em controles periódicos (inicial, 30 dias, 180 dias e 1 ano após a cimentação). Grupos formados por observadores externos (pacientes, alunos de 1º e último ano de graduação, pós-graduandos e especialistas) avaliaram, aleatoriamente, as imagens obtidas inicialmente e ao final do tratamento, segundo perguntas sobre a satisfação ou não com o resultado estético do caso. Resultados: Os dados obtidos com o espectrofotômetro foram submetidos a testes estatísticos que revelaram diferença significativa apenas entre os tempos avaliados, contudo, para todos os tipos de restauração foi observada estabilidade de cor após, no máximo, 180 dias da cimentação. Não houve diferença estatística entre a satisfação dos diferentes grupos de observadores externos com o resultado estético dos casos tanto para as fotografias quanto para os vídeos, embora estes tenham obtido maior número de respostas...

Introduction: The process of interpretation of color in thin ceramic restorations pre- and post-treatment is challenging. The evaluation methods of the results are diverse and literature is not clear in pointing out the most effective method. The question is even more relevant given the variation of the resin cement used. Purpose: After changing the type of resin cement used, the aim of this study was to evaluate the color behavior of ceramic restorations in teeth with aesthetic demand, over 1 year after treatment, with the help of different monitoring methods (spectrophotometer, photographs, videos and clinical assessment) in a longitudinal and prospective study. Materials and Methods: 28 patients were selected, for a total of 204 restored teeth (89 veneers, 57 crowns and 58 contact lenses). 76 restorations were cemented with Rely X veneer, 71 with Variolink veneer and 57 with Rely X U200. Color measurements were made with a spectrophotometer, digital photos and videos taken during treatment and periodic controls (initial, 30 days, 180 days and 1 year after cementation). Groups formed by outside observers (patients, students of 1st and last year of undergraduate, graduate students, and experts) evaluated, randomly, images obtained initially and after treatment, according to questions on satisfaction or not with the aesthetic outcome of the case. Results: The data obtained with the spectrophotometer were subjected to statistical tests which showed a significant difference only between the time periods; however, for all types of restoration, color stability was observed after a maximum of 180 days after cementation. There was no statistical difference between the satisfaction of different groups of outsiders observers with the aesthetic result of the cases for both the photos and for videos, although they videos have obtained the highest number of satisfactory answers. Conclusion: The photographs were effective in cases analysis and limitations, while dynamic...

Análise do comportamento da cor de restaurações cerâmicas sem metal avaliadas por diferentes métodos: estudo clínico prospectivo / Color behavior of ceramic metal free restorations evaluated by different methods; prospective clinical study

Introdução: O processo de interpretação da cor em restaurações cerâmicas delgadas pré e pós-tratamento é um desafio. Os métodos de avaliação dos resultados são diversos e a literatura não é clara em apontar o mais eficaz e eficiente. A questão é ainda mais relevante diante da variação do cimento resinoso utilizado. Proposição: Após variar o tipo de cimento resinoso utilizado, o objetivo deste estudo foi avaliar o comportamento da cor de restaurações cerâmicas em dentes com demanda estética, ao longo de 1 ano após o tratamento, com o auxílio de diferentes métodos de acompanhamento (espectrofotômetro, fotografias, vídeos e avaliação clínica) em um estudo clínico longitudinal e prospectivo. Materiais e Métodos: Foram selecionados 28 pacientes, perfazendo um total de 204 dentes restaurados (89 facetas laminadas, 57 coroas totais ou parciais e 58 lentes de contato). 76 restaurações foram cimentadas com Rely X veneer, 71 com Variolink veneer e 57 com Rely X U200. Foram realizadas mensurações de cor com espectrofotômetro, fotografias digitais e vídeos gravados no decorrer do tratamento e em controles periódicos (inicial, 30 dias, 180 dias e 1 ano após a cimentação). Grupos formados por observadores externos (pacientes, alunos de 1º e último ano de graduação, pós-graduandos e especialistas) avaliaram, aleatoriamente, as imagens obtidas inicialmente e ao final do tratamento, segundo perguntas sobre a satisfação ou não com o resultado estético do caso. Resultados: Os dados obtidos com o espectrofotômetro foram submetidos a testes estatísticos que revelaram diferença significativa apenas entre os tempos avaliados, contudo, para todos os tipos de restauração foi observada estabilidade de cor após, no máximo, 180 dias da cimentação. Não houve diferença estatística entre a satisfação dos diferentes grupos de observadores externos com o resultado estético dos casos tanto para as fotografias quanto para os vídeos, embora estes tenham obtido maior número de respostas...

Introduction: The process of interpretation of color in thin ceramic restorations pre- and post-treatment is challenging. The evaluation methods of the results are diverse and literature is not clear in pointing out the most effective method. The question is even more relevant given the variation of the resin cement used. Purpose: After changing the type of resin cement used, the aim of this study was to evaluate the color behavior of ceramic restorations in teeth with aesthetic demand, over 1 year after treatment, with the help of different monitoring methods (spectrophotometer, photographs, videos and clinical assessment) in a longitudinal and prospective study. Materials and Methods: 28 patients were selected, for a total of 204 restored teeth (89 veneers, 57 crowns and 58 contact lenses). 76 restorations were cemented with Rely X veneer, 71 with Variolink veneer and 57 with Rely X U200. Color measurements were made with a spectrophotometer, digital photos and videos taken during treatment and periodic controls (initial, 30 days, 180 days and 1 year after cementation). Groups formed by outside observers (patients, students of 1st and last year of undergraduate, graduate students, and experts) evaluated, randomly, images obtained initially and after treatment, according to questions on satisfaction or not with the aesthetic outcome of the case. Results: The data obtained with the spectrophotometer were subjected to statistical tests which showed a significant difference only between the time periods; however, for all types of restoration, color stability was observed after a maximum of 180 days after cementation. There was no statistical difference between the satisfaction of different groups of outsiders observers with the aesthetic result of the cases for both the photos and for videos, although they videos have obtained the highest number of satisfactory answers. Conclusion: The photographs were effective in cases analysis and limitations, while dynamic...

Influence of voids in the hybrid layer based on self-etching adhesive systems: a 3-D FE analysis

The presence of porosities at the dentin/adhesive interface has been observed with the use of new generation dentin bonding systems. These porosities tend to contradict the concept that etching and hybridization processes occur equally and simultaneously. Therefore, the aim of this study was to evaluate the micromechanical behavior of the hybrid layer (HL) with voids based on a self-etching adhesive system using 3-D finite element (FE) analysis. MATERIAL AND METHODS: Three FE models (Mr) were built: Mr, dentin specimen (41x41x82 μm) with a regular and perfect (i.e. pore-free) HL based on a self-etching adhesive system, restored with composite resin; Mp, similar to M, but containing 25 percent (v/v) voids in the HL; Mpp, similar to Mr, but containing 50 percent (v/v) voids in the HL. A tensile load (0.03N) was applied on top of the composite resin. The stress field was obtained by using Ansys Workbench 10.0. The nodes of the base of the specimen were constrained in the x, y and z axes. The maximum principal stress (σmax) was obtained for all structures at the dentin/adhesive interface. RESULTS: The Mpp showed the highest peak of σmax in the HL (32.2 MPa), followed by Mp (30 MPa) and Mr (28.4 MPa). The stress concentration in the peritubular dentin was high in all models (120 MPa). All other structures positioned far from voids showed similar increase of stress. CONCLUSION: Voids incorporated into the HL raised the σmax in this region by 13.5 percent. This behavior might be responsible for lower bond strengths of self-etching and single-bottle adhesives, as reported in the literature.

Influência da espessura da camada de cimento e da variação da temperatura no comportamento mecânico de fragmentos cerâmicos utilizados em restaurações estéticas / Influence of cement layer thickness and variation of temperature in the mechanics of ceramics fragments used in esthetics restoration

Introdução: Fragmentos cerâmicos têm sido utilizados como opção restauradora em dentes anteriores com necessidade de pequenas correções de contorno e forma. A espessura da camada de cimento resinoso e a variação da temperatura intra-bucal são fatores influentes no sucesso das restaurações cerâmicas convencionais como inlays, onlays, coroas e laminados. Entretanto, a literatura não apresenta dados sobre a influência destes dois fatores no comportamento mecânico do fragmento cerâmico que geralmente apresenta dimensões não uniformes, principalmente nos limites da restauração. Proposição: O objetivo do presente estudo é analisar, através do método dos elementos finitos tridimensional (EF 3-D), o comportamento da camada de cimento resinoso e da cerâmica, variando a espessura da camada de cimento e a temperatura intra-bucal. Materiais e Métodos: Após a obtenção do conjunto de imagens microtomográficas de um incisivo central maxilar, o modelo sólido do dente será elaborado no programa Mimics. A partir deste modelo inicial (M), 5 modelos serão elaborados no programa SolidWorks, simulando a restauração do ângulo disto-incisal com o uso de um fragmento cerâmico colado ao substrato dental, variando a espessura da camada de cimento resinoso: M1 – 0 μm de espessura; M2 – 50 μm em toda extensão; M3 – 50 μm nas margens e 100 μm à distância; M4 – com 50 μm nas margens e 200 μm à distância; e M5 – com 100 μm nas margens e 200 μm à distância. Para todos os modelos, serão simuladas 4 variações de temperatura similares às mudanças que ocorrem na cavidade bucal (5°C, 20°C, 37°C, e 50°C). A malha de elementos finitos será refinada segundo a convergência da análise, a ser realizada no programa Ansys Workbench. Resultados: A tensão principal máxima no fragmento cerâmico nos modelos M1 a M5 sob temperatura de 5ºC foi (MPa): 7,81; 7,82; 27,3; 27,4 e 1,83, respectivamente. Para 50ºC, os valores foram 35,6; 35,6; 87,6; 79,2 e 25,9, respectivamente. Conclusões: O fragmento cerâmico...

Introduction: Ceramics fragments have been used for dental/aesthetic restorative purposes in the anterior dentition. The cement layer thickness and temperature variation play an important role for the adequate biomechanical behavior of the ceramics in case of inlays, onlays, total crown and laminate veneers. However, those aspects has not been evaluated in case of ceramics fragments that usually shows non-uniform dimension and shape which might have negative influence in the behavior of dental ceramics fragments. Purpose: The aim of this study was evaluated by 3-D finite element analysis the mechanical behavior of the cement layer and ceramic fragment varying the cement layer thickness and the temperature. Materials and Methods: After obtaining the microtomography data set of a maxillary central incisor, the solid model was rebuild using Mimics program. The model was exported to the Solidworks program for the simulation of a defect at the distal/incisal edge. This defect was restored with a ceramic fragment bonded to the enamel surface. From this restored model (M), 5 different models were tested: M1 – cement layer (CL) showing 0 μm of thickness; M2 – CL with an uniform thickness of 50 μm; M3 – CL with 50 μm at the margin of ceramics and 100 μm in the inner area; M4 – CL with 50 μm at the margin of ceramics and 200 μm in the inner area; and M5 – CL with 100 μm at the margin of ceramics and 200 μm in the inner area. In all models, the environment temperature changed from 5ºC to 50ºC in 4 increments. The finite element (FE) mesh was refined drove by convergence of analysis. The numerical approach was performed using Ansys Workbench FE program. Results: The maximum principal stress in the ceramic fragment under 5ºC was (M1 to M5) (MPa): 7.81, 7.82, 27.3, 27.4 and 1.83, respectively. For 50ºC, the values were 35.6, 35.6, 87.6, 79.2 and 25.9, respectively. Conclusions: The ceramics fragments showed higher values of tensile stress as there was an increase of the…