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1.
Braz. j. oral sci ; 23: e240950, 2024. ilus
Article in English | LILACS, BBO | ID: biblio-1527011

ABSTRACT

Aim: The aim of this in vitro study was to compare machine and manual cementation of prosthetic elements by measuring internal and marginal fits. Methods: Eighteen anatomic prefabricated abutments were used to manufacture zirconia copings in the Ceramill (n=9) and Lava systems (n=9). The copings were cemented with a fluid consistency addition silicone using a machine (n=18) and manually (n=18) according to the replica technique. They were then cut in the buccal-palatal and mesial-distal directions. The film thickness was photographed using an optical microscope and measured in the internal and marginal regions. The data collected were analyzed by repeated measures ANOVA and Bonferroni's multiple comparison test (∂=.05). The Bland-Altman test was performed to evaluate the agreement between the methods. Results: In the evaluation of the internal and marginal misfits, the mean values observed for the cementation performed with the aid of a machine and manually, were as follows: angular regions, 76.7 µm and 76.2 µm; linear regions, 60.6 µm and 60.7 µm; incisal region, 144.8 µm and 145.2 µm; marginal region, 40.1 µm and 40.2 µm; and overall mean, 80.4 µm and 80.6 µm, respectively. No significant differences were found between the 2 methods, for any of regions and systems (P>.05). The Bland-Altman test showed agreement between the methods (P>.05) and that the limits of agreement found were clinically acceptable. Conclusions: Within the limitations of this in vitro study, we can conclude that cementation using manual techniques or mechanical aid produces the same cement films


Subject(s)
Cementation , Dental Prosthesis Design , Computer-Aided Design , Dental Marginal Adaptation
2.
Braz. j. oral sci ; 23: e243158, 2024. ilus
Article in English | LILACS, BBO | ID: biblio-1527026

ABSTRACT

Aim: In recent years, great advances have been made in the use of CAD/CAM to prepare fixed restorations. The marginal and internal fit of these restorations is a principal determinant for their clinical success. In addition, the nature of the oral environment affects the mechanical properties of these restorations. Therefore, this study aimed to investigate the effect of aging process under conditions that simulate the oral environment on the marginal adaptation, and, fracture resistance of crowns fabricated from polyether ether ketone (PEEK) using CAD/CAM methods. Methods: Twenty identical crown restorations were fabricated by using CAD/CAM methods to mill polyether ether ketone (PEEK) material. These crowns were produced by using a software design of an epoxy resin replica of the prepared maxillary first premolar tooth. All PEEK crowns were cemented and randomly divided into two equal groups (A, B). Each group was divided into subgroups (A1, A2 and B1, B2). Group A1 and A2 were used to measure marginal adaptation and fracture resistance, respectively, before aging, while group (B1 and B2) were measured after aging. The cemented crowns were mounted in resin molds to facilitate the sectioning process. The measurements of the marginal gap were performed after sectioning at four points using a stereomicroscope. The fracture resistance of the crowns was investigated using a universal testing machine. A statistical analysis was performed using the GraphPad Prism® software version and unpaired Student's t-test. Results: The results revealed that aging affected the marginal gap, and the fracture resistance of the PEEK crowns. While aging, negatively affected the conditions under investigation, however the least significant difference of marginal gap was found in the margin region. Conclusions: PEEK-CAD/CAM is considered as a good alternative prosthodontic material for fixed prostheses. The CAD/CAM technique used to make PEEK crown restorations in our study offers the advantages of high marginal accuracy and fracture resistance for long-term performance in the oral environment


Subject(s)
Polymers , Aging , Computer-Aided Design , Dental Marginal Adaptation , Crowns , Flexural Strength , Ketones
3.
Rev. ADM ; 80(4): 190-196, jul.-ago. 2023. ilus, tab
Article in Spanish | LILACS | ID: biblio-1525858

ABSTRACT

Introducción: la adaptación marginal e interna de nuestras restauraciones fabricadas por fundición sistemas de fresado y sinterización láser es uno de los factores clínicos más importantes para el éxito de las prótesis fijas, previniendo el riesgo de microfiltración y enfermedad periodontal. Objetivo: evaluar la adaptación marginal e interna de cofias metálicas en aleación Cr-Co confeccionadas por técnicas convencionales, CAD/ CAM de fresado y sinterizado por láser. Material y métodos: estudio de tipo experimental, comparativo e in vitro. Se imprimió un modelo maestro en Cr-Co, proveniente del escaneo de un premolar preparado para corona completa, sobre el cual se diseñaron 30 cofias divididas en tres grupos: el primero que corresponde al grupo cofias fundidas fresadas en disco de cera A (A = 10), el segundo grupo cofias fresadas en disco de metal presinterizado B (B = 10) y el tercer grupo cofias impresas por sinterización láser C (C = 10). Se empleó la réplica de silicona, colocando silicona al interior de cada cofia, sobre el modelo maestro, simulando al cemento, mediante una máquina de ensayo universal se realizó una compresión de 50 N. Luego de retirar cada cofia se rellenaron con silicona pesada de adición, obteniendo una réplica de silicona. Se efectuaron dos cortes transversales en sentido vestíbulolingual y mesiodistal. Se observó el espesor de silicona VPS (vinil poliéter silicona) mediante un estereomicroscopio (Nikon SMZ745T), obteniendo valores en micrómetros. Para el análisis estadístico se utilizó el software SPSS 25 con el fin de realizar la prueba de normalidad y ANOVA de dos vías bajo un nivel de confianza del 95%. Resultados: el menor gap lo obtuvo el grupo de fresadas, seguido de las impresas y por último las fundidas por métodos convencionales. ANOVA de dos vías reveló diferencias estadísticamente significativas entre los tres grupos (p < 0.0001). Conclusiones: se encontró que el gap varía con cada método de fabricación, la técnica convencional de fundido mostró un mayor gap, ninguna excediendo el rango clínicamente aceptable (AU)


Introduction: the marginal and internal adaptation of our restorations manufactured by casting, milling systems and laser sintering is one of the most important clinical factors for the success of fixed prostheses, preventing the risk of microleakage and periodontal disease. Objective: evaluate the marginal and internal adaptation of metal copings in Cr-Co alloy made by conventional techniques, CAD/CAM milling and laser sintering. Material and methods: an experimental, comparative and in vitro study, a Cr-Co master model was printed from the scan of a premolar prepared for a full crown. An experimental, comparative and in vitro study, a Cr-Co master model was printed from the scan of a premolar prepared for a full crown, on which 30 caps divided into three groups were designed; the first group corresponds to the cast copings milled on a wax disc A (A = 10), the second group milled copings on a presintered metal disc B (B = 10) and the third group printed by laser sintering copings C (C = 10). The silicone replica was used, placing silicone inside each coping, on the master model, simulating cement, using a universal testing machine, a 50 N compression was performed. After removing each coping, they were filled with heavy addition silicone, obtaining a silicone replica. Two cross-sections were made in the buccolingual and mesiodistal direction., observing the thickness of the VPS (vinyl polyeter silicone) silicone using a stereomicroscope (Nikon SMZ745T), obtaining values in micrometers. For the statistical analysis, the SPSS 25 software was used in order to perform the normality and two-way ANOVA tests under a 95% confidence level. Results: the smallest gap was obtained by the milled group, followed by the printed ones and finally those cast by conventional methods. Two-way ANOVA revealed statistically significant differences between the three groups (p < 0.0001). Conclusions: the gap was found to vary with each fabrication method, the conventional casting technique showed a larger gap, none exceeding the clinically acceptable range (AU)


Subject(s)
Chromium Alloys , Computer-Aided Design , Dental Marginal Adaptation , Crowns , Lasers , In Vitro Techniques , Analysis of Variance
4.
Braz. dent. sci ; 26(3): 1-12, 2023. ilus, tab
Article in English | LILACS, BBO | ID: biblio-1511733

ABSTRACT

Objective:This study evaluated the effect of immediate dentin sealing on the marginal adaptation of lithium disilicate overlays with three different types of resin-luting agents: preheated composite, dual-cure adhesive resin, and flowable composite. Materials and Methods: Forty-eight maxillary first premolars of similar size were prepared with a butt joint preparation design. The teeth were separated into two primary groups, each with twenty-four teeth: Group DDS: Delay dentin sealing (non-IDS) teeth were not treated. Group IDS: dentin sealing was applied immediately after teeth preparation. Each group was subsequently separated into three separate subgroups. Subgroups (DDS+Phc, IDS+Phc): cemented with preheated composite (Enamel plus HRi, Micerium, Italy), Subgroups (DDS+Dcrs, IDS+Dcrs): cemented with dual-cured resin cement (RelyX Ultimate, 3M ESPE, Germany) and Subgroups (DDS+Fc, IDS+Fc): Cemented with flowable composite (Filtek supreme flowable, 3M ESPE, USA). Using a digital microscope with a magnification of 230x, the marginal gap was measured before and after cementation at four different locations from each surface of the tooth, and the mean of measurements was calculated and analyzed statistically using the independent t-test, one-way ANOVA test, Bonferroni correction at a significance level of 0.05. Results: The samples that were immediately sealed with dentin bonding agent showed lower marginal gaps than delayed dentin sealing, both pre-and post-cementation for all subgroups, with a statistically significant difference (p˂0.01). The marginal gap was significantly lower in the IDS+Fc (48.888 ±5.5 µm) followed by the IDS+Dcrs group (53.612 ±5.8 µm) and IDS+Phc (79.19 9±6.9 µm) respectively, while the largest marginal gaps were observed in the DDS+Phc group (86.505 ±5.4 µm). Conclusion: Generally, the teeth with IDS showed better marginal adaptation than teeth without IDS. The marginal gap was smaller with flowable composite and dual-cure resin cement than with preheated composite (AU)


Objetivo:Esse estudo avaliou o efeito do selamento imediato da dentina na adaptação marginal de overlays em dissilicato de lítio com três tipos diferentes de agentes de cimentação resinosos: resina composta pré-aquecida, adesivo resinoso dual e resina fluida. Materiais e métodos: Quarenta e oito primeiros pré-molares maxilares com tamanho similar foram preparados com término em ombro. O dente foi separado em dois grupos primários, cada um com vinte e quatro dentes: Grupo DDS: retardado selamento da dentina (non-IDS) dente não foi tratado. Grupo IDS: selamento dentinário foi aplicado imediatamente após a preparação do dente. Cada grupo foi separado de modo subsequente em três subgrupos. Subgrupo (DDS+Phc, IDS+Phc): cimentado com resina pré-aquecida (Enamel plus HRi, Micerium, Italy), Subgrupo (DDS+Dcrs, IDS+Dcrs): cimentado com cimento resinoso dual (RelyX Ultimate, 3M ESPE, Germany) e Subgrupo (DDS+Fc, IDS+Fc): cimentado com resina fluida (Filtek supreme flowable, 3M ESPE, USA). Usando um microscópio digital com magnificação de 230x, o gap marginal foi medido antes e após a cimentação em quatro diferentes localizações de cada superfície do dente e a média das medidas foi calculada e estatisticamente analisada através do uso do teste ANOVA um-fator e teste independente de Tukey e correção Bonferroni com nível de significância de 0,05. Resultado: As amostras que foram imediatamente seladas com agente adesivo dentinário apresentaram menores gaps marginais do que o selamento dentinário retardado, ambos pré e pós cimentação para todos os subgrupos apresentaram diferença estatística significante (p˂0.01). O gap marginal foi significativamente menor para IDS+Fc (48.888 ±5.5 µm) acompanhado do IDS+Dcrs group (53.612 ±5.8 µm) e IDS+Phc (79.19 9 ±6.9 µm) respectividamente, enquanto o maior gap marginal foi observado no grupo DDS+Phc (86.505 ±5.4 µm). Conclusão:Geralmente, o dente com IDS apresentou melhor adaptação marginal do que o dente sem IDS. O gap marginal foi menor com resina fluida e cimento resinoso dual do que com a resina composta pré-aquecida (AU)


Subject(s)
Cementation , Computer-Aided Design , Dental Marginal Adaptation , Resin Cements , Dental Porcelain
5.
Braz. j. oral sci ; 21: e228852, jan.-dez. 2022. ilus
Article in English | LILACS, BBO | ID: biblio-1392917

ABSTRACT

Aim: To evaluate the occlusal and internal marginal adaptation of inlay restorations made of different materials, using CAD-CAM. Methods: Preparations were made for MOD inlays of one-third intercuspal width and 4 mm depth in 30 third human molars. The teeth were restored using CAD-CAM materials (n=10) of nanoceramic resin (Lava Ultimate), polymer-infiltrated ceramic network (VITA ENAMIC), or lithium disilicate glass-ceramic (IPS e.max CAD). The specimens were cemented with dual resin cement and sectioned at the center of the restoration, after which the two halves were evaluated, and photographed The occlusal and internal discrepancy (µm) was determined at five points: cavosurface angle of the occlusal-facial wall (CA-O); center of the facial wall (FW); faciopulpal angle (FPA); center of the pulpal wall (PW); and center of the lingual wall (LW). The data were submitted to the Kruskal-Wallis and the Dunn tests (α=0.05). Results: No difference was observed among the materials regarding the occlusal discrepancy at the CA-O, FPA, or PW internal points. The e.max CAD measurement at FW showed larger internal discrepancy than that of Lava (p=0.02). The internal discrepancy at LW was greater for e.max CAD than VITA ENAMIC (p=0.02). Conclusion: Lithium disilicate glass-ceramic presented greater internal discrepancy in relation to the surrounding walls of the inlay preparations


Subject(s)
Ceramics , Computer-Aided Design , Dental Marginal Adaptation , Dental Materials , Inlays
6.
Braz. j. oral sci ; 21: e225136, jan.-dez. 2022. ilus
Article in English | LILACS, BBO | ID: biblio-1354771

ABSTRACT

Aim: To evaluate the influence of cobalt-chromium (Co-Cr) coping fabrication methods and ceramic application on the marginal and internal fit of metal-ceramic crowns. Methods: Co-Cr copings for metal-ceramic crowns were prepared by lost wax casting or CAD-CAM machining of sintered blocks. The fit was analyzed using the silicone replica technique at four assessment points: marginal gap (MG), axial wall (AW), axio-occlusal (AO) angle, and central occlusal (CO) wall. After the initial analysis, the copings were ceramic-veneered with the layering technique, and the fit was again determined. Data were statistically analyzed by paired and unpaired Student's-t test (α=0.05). Results: Marginal and internal fit before ceramic application according to the coping manufacturing method showed significant differences only at CO (p < 0.001), with milled copings (137.98±16.71 µm) showing higher gap values than cast copings (112.86±8.57 µm). For cast copings, there were significant differences at MG (before 109.13±8.79 µm; after 102.78±7.18 µm) and CO (before 112.86±8.57 µm; after 104.07±10.63 µm) when comparing the fit before and after ceramic firing. For milled copings, there was significant difference only at AO (before 116.39±9.64 µm; after 108.54±9.26 µm). Conclusion: This study demonstrated that the coping fabrication method influenced the internal fit. Ceramic firing maintained or improved the fit of the metal-ceramic crowns. The marginal discrepancy of all restorations, before and after ceramic firing, can be considered clinically acceptable


Subject(s)
Ceramics , Metal Ceramic Alloys , Dental Marginal Adaptation , Crowns
7.
Braz. dent. sci ; 25(3): 1-10, 2022. ilus
Article in English | LILACS, BBO | ID: biblio-1381618

ABSTRACT

The clinical success of tooth-colored indirect restorations has been confirmed in several studies. However, inlays and onlays restorations in Class II cavities with deep gingival margins can still be considered a clinical challenge. With the purpose of facilitating the execution of the operative procedures in intrasulcular margins and reducing the risk of restorative failures, the technique of cervical margin relocation has been explored as a noninvasive alternative to surgical crown lengthening. This work aims at discussing through a case report the biomechanical, operative and biological aspects in the treatment of teeth with deep gingival margins. Therefore, given the therapy applied in the clinical case presented, it is concluded that the cervical margin relocation with composite resin is advantageous since it eliminates the need for surgery, allowing the implementation of indirect restorations in fewer clinical sessions, not causing damage to periodontal tissues once it provided good finishing and polishing with the establishment of a correct emergence profile, allowing flawless maintenance of gingival health after one year. (AU)


Sucesso clínico das restaurações indiretas livres de metal tem sido confirmado em diversos estudos. No entanto, restaurações parciais indiretas em cavidades do tipo classe II com margens profundas ainda podem ser consideradas um desafio clínico. Com a proposta de facilitar a execução dos procedimentos operatórios em margens intra-sulculares e reduzir a ocorrência de falhas, a técnica de elevação da margem gengival em resina composta tem sido explorada como alternativa não invasiva à cirurgia de aumento de coroa clínica. Este trabalho tem a intenção de discutir através de um relato de caso clínico os aspectos biomecânicos, operatórios e biológicos no tratamento de dentes com margens cervicais profundas. Sendo assim, conclui-se que a técnica de elevação da margem gengival com resina composta é vantajosa, pois elimina a necessidade de cirurgia permitindo a execução de restaurações indiretas em menos sessões clínicas, não gerando danos aos tecidos periodontais, desde que haja um bom acabamento e polimento, com estabelecimento de um correto perfil de emergência. (AU)


Subject(s)
Humans , Female , Adult , Dental Marginal Adaptation , Composite Resins , Dental Restoration Failure , Dental Cavity Preparation , Inlays
8.
Pesqui. bras. odontopediatria clín. integr ; 22: e210110, 2022. tab, graf
Article in English | LILACS, BBO | ID: biblio-1422262

ABSTRACT

Abstract Objective: To evaluate the effect of two types of light-curing units (second and third generations) and two types of bulk-fill composite resins with different photoinitiators - Tetric N-Ceram Bulk Fill (TNCB) and Xtra Fil (XTF) on gap formation at the gingival margins of Cl II restorations. Material and Methods: Fifty-six standard Cl II cavities were prepared on the mesial and distal surfaces of premolar teeth, with the gingival margin of the cavities 1 mm apical to the CEJ. The samples were randomly assigned to two groups based on the composite resin type and two subgroups based on the light-curing unit type and restored. After 5000 rounds of thermocycling, gingival margin gap in each sample was measured in µm under an electron microscope at ×2000 magnification. Data were analyzed by two-way ANOVA and Tukey tests (α=0.05). Results: Marginal gaps of TNCB composite resin were significantly smaller than those of XTF composite resin (p<0.001). There were no significant differences between the two light-curing units in each group (p=0.887 with XTF and p=0.999 with TNCB). Conclusion: The gaps at gingival margins of Cl II cavities with TNCB bulk-fill composite were smaller than XTF composite resin. Both composite resins can be cured with both the second- and third-generation LEDs (AU).


Subject(s)
Humans , Bicuspid , Dental Marginal Adaptation , Composite Resins/chemistry , Light-Curing of Dental Adhesives/instrumentation , Photoinitiators, Dental/chemistry , In Vitro Techniques/methods , Microscopy, Electron, Scanning/instrumentation , Analysis of Variance
9.
Pesqui. bras. odontopediatria clín. integr ; 22: e210145, 2022. tab, graf
Article in English | LILACS, BBO | ID: biblio-1422284

ABSTRACT

Abstract Objective: To compare the marginal degradation (susceptibility to marginal adaptation and marginal discoloration) of composite restorations placed in class II and V cavities using conventional and bulk-fill resin composites. Material and Methods: This study was approved by PROSPERO database (#42020201596). PubMed, Scopus, Embase, Web of Science, Lilacs, Cochrane, Open Grey, Clinical Trials, and Rebec databases were searched by three independent investigators using MeSH terms, supplementary concepts, synonyms, and free keywords, based on the PICOS strategy (P, population: restoration in permanent teeth; I, intervention: bulk-fill resin composite; C, comparison: conventional resin composite; O, outcome: marginal discoloration and adaptation; and S, study design: randomized and non-randomized clinical trials). The risk of bias was evaluated according to the Cochrane Collaboration's tool, the meta-analyses by RevMan software, the certainty of evidence by the Grading of Recommendations Assessment, Development, and Evaluation, and the leave-one-out sensitivity test. The prevalence of successful events and the total number of restorations were used to calculate the risk difference at a confidence interval of 95%, according to a fixed-effect model. The heterogeneity was evaluated using the I2 index. Results: 16 from 10,780 studies were selected and included for qualitative and quantitative analysis. Two studies were considered as high risk of bias, one showing some concerns, and 13 as low risk of bias. Four meta-analyses evaluated the marginal adaptation and marginal discoloration in class II and V cavities, with a nonsignificant heterogeneity (I2 = 0%, p>0.05). The certainty of evidence was considered high, except for two subgroups of each outcome. Conclusion: There is evidence that composite restorations using conventional and bulk-fill resin composites present similar clinical performance related to marginal degradation (AU).


Subject(s)
Meta-Analysis as Topic , Sensitivity and Specificity , Composite Resins , Systematic Reviews as Topic , Dental Marginal Adaptation
10.
Rev. odontol. UNESP (Online) ; 51: e20220016, 2022. tab
Article in English | LILACS, BBO | ID: biblio-1424227

ABSTRACT

Introduction: composite resins are materials widely used for Class II restorations, to restore the anatomization of the dental element. However, there are several factors that can interfere with the quality of a good restoration. Objective: the objective of the present study is to carry out a retrospective evaluation of the clinical performance of Class II restorations performed by undergraduate students of Dentistry at the Escola São Francisco de Assis (ESFA), and to identify the main errors. Material and method: we selected the medical records of patients treated in the disciplines of Dentistry II, Integrated I and II in the Dentistry clinic at ESFA, which presented detailed information on the Class II procedure, as well as initial radiographic examinations, using the FDI method. The sample consisted of 33 medical records that included 72 teeth. Result: it was observed that more than 80% of the restorations were classified as acceptable. And, only 19.44% of the restorations were unacceptable, failing due to functional and biological properties. Conclusion: it was found that undergraduate students in Dentistry at ESFA, who are guided by professors to perform treatments following pre-established clinical protocols, are capable of carrying out quality restorative procedures.


Introdução: as resinas compostas são materiais muito utilizados para restaurações Classe II, com função de restabelecer a anatomização do elemento dental. No entanto, diversos são os fatores que podem interferir na qualidade de uma boa restauração. Objetivo: o objetivo do presente estudo é realizar uma avaliação retrospectiva do desempenho clínico de restaurações Classe II executadas por alunos da graduação de Odontologia da Escola São Francisco de Assis (ESFA) e identificar as principais falhas cometidas. Material e método: foram selecionados os prontuários dos pacientes atendidos nas disciplinas de Dentística II, Integrada I e II na clínica de Odontologia da ESFA, que apresentaram as informações detalhadas do procedimento de Classe II, bem como exames radiográficos iniciais, usando o método FDI. A amostra foi composta por 33 prontuários que incluíam 72 dentes. Resultado: observou-se que mais de 80% das restaurações foram classificadas como aceitáveis. Visto que, apenas 19,44% das restaurações estiveram inaceitáveis, pecando para as propriedades funcionais e biológicas. Conclusão: constatou-se que os alunos da graduação em Odontologia da ESFA, os quais são orientados por professores a realizar tratamentos seguindo protocolos clínicos pré-estabelecidos, são capazes de confeccionar procedimentos restauradores de qualidade.


Subject(s)
Students, Dental , Data Interpretation, Statistical , Dental Marginal Adaptation , Composite Resins , Inlays
11.
Araçatuba; s.n; 2022. 127 p. tab, graf, ilus.
Thesis in Portuguese | LILACS, BBO | ID: biblio-1435801

ABSTRACT

Atualmente, devido a perda do elemento dentário e a procura por um tratamento estético e principalmente funcional, a reabilitação com próteses sobre implante tem sido amplamente empregada, com elevada previsibilidade a longo prazo. Com isso, muito tem sido relatado na literatura acerca das possíveis complicações dessa modalidade de tratamento, principalmente relacionado às possibilidades de falhas mecânicas das próteses implantossuportadas. Por isso, o objetivo do presente projeto foi avaliar a influência na adaptação marginal e interna, da utilização do intermediário protético e do tipo de retenção das próteses (parafusada e cimentada) em implantes cone morse submetidos à ciclagem mecânica. Foram confeccionados 40 corpos de prova, no qual cada um tinha a presença de um implante, com as dimensões de 4mm de diâmetro e 11,5mm de comprimento cone morse (n = 40). Dessa forma, foi avaliado a influência da utilização do intermediário e dos sistemas de retenção em cada conexão de maneira específica. Metade dos corpos de prova de cada sistema de conexão foram confeccionados em UCLA (n=20, sendo 10 parafusadas e 10 cimentadas), enquanto que a outra metade foi utilizado um intermediário pré-fabricado (Pilar Universal (n=20, sendo 10 parafusadas e 10 cimentadas). Os corpos de prova foram submetidos à ciclagem mecânica submersos em água destilada simulando um tempo clínico de cinco anos. Além disso, foram avaliados quanto ao torque e destorque (N) e adaptação marginal e interna (µm) antes e após a ciclagem mecânica. Os dados provenientes das mensurações foram organizados em tabela em formato Excel (Microsoft Office Excel, Redmond, WA, Estados Unidos) e submetidos ao software SigmaPlot (SigmaPlot, San Jose, CA, EUA) versão 12.0. Todos os dados foram analisados inicialmente com a utilização da estatística descritiva. Em seguida, os dados para intrusão (valores positivos), extrusão (valores negativos), destorque inicial, destorque final, e descimentação foram analisados em relação a distribuição de normalidade (teste Shapiro-Wilk e igualdade de variância) e, posteriormente, foi adotada a Análise de Variância (ANOVA) a um fator (Grupos diferentes materiais: G1 a G4), quando houve normalidade dos dados, o pós teste de Tukey foi adotado para as comparações múltiplas, quando não foi identificado uma distribuição normal, empregou-se o teste de Kruskall-Wallis e pós-teste de Dunn's ou Tukey, semelhantemente foi realizada a análise específica das variáveis pilares (UCLA e Pilar Universal) e sistemas de retenção (Parafusado e Cimentado). Para todos os testes aplicou-se nível de significância de 5% (α=0,05). A análise gráfica foi considerada através de um gráfico de barras para os dados que apresentaram normalidade com valores de média e desvio padrão, e as demais análises que não apresentaram normalidade foi considerado a confecção de um boxplot para cada grupo comparativo. As próteses sobre implante utilizando pilares em zircônia tem ganhado cada vez mais espaço, além do estudo in vitro, foi realizada uma revisão sistemática para comparar a perda óssea marginal e as complicações próteticas de reabilitações utilizando pilares de zircônia cimentado e parafusado. Em relação as próteses cimentadas e parafusadas, devido as evidências conflitantes e a presença de muitas revisões sistemáticas sobre o tema, foi realizada uma overview de revisões sistemáticas, com o objetivo de compilar as informações disponiveis e avaliar a qualidade metodologica desses estudos a respeito das complicações presentes nas próteses sobre implante cimentadas ou parafusadas(AU)


Currently, due to the loss of the dental element and the search for an aesthetic and mainly functional treatment, rehabilitation with implant prostheses has been widely used, with high long-term predictability. Thus, much has been reported in the literature about the possible complications of this treatment modality, mainly related to the possibility of mechanical failure of implant-supported prostheses. Therefore, the objective of the present project was to evaluate the influence on the marginal and internal adaptation, the use of the prosthetic intermediate and the type of retention of the prostheses (screwed and cemented) in morse taper implants submitted to mechanical cycling. 40 specimens were made, in which each one had an implant, with dimensions of 4 mm in diameter and 11.5 mm in length (n = 40). In this way, the influence of the use of intermediaries and retention systems in each connection was evaluated in a specific way. Half of the specimens of each connection system were made in UCLA (n=20, being 10 screwed and 10 cemented), while the other half was used a prefabricated intermediate (Universal Abutment (n=20, being 10 screwed) and 10 cemented). The specimens were submitted to mechanical cycling submerged in distilled water simulating a clinical time of five years. In addition, they were evaluated for torque and detorque (N) and marginal and internal adaptation (µm) before and after mechanical cycling. Data from measurements were organized in a table in Excel format (Microsoft Office Excel, Redmond, WA, USA) and submitted to SigmaPlot software (SigmaPlot, San Jose, CA, USA) version 12.0. All data were initially analyzed using descriptive statistics. Then, data for intrusion (positive values), extrusion (negative values), initial detorque, final detorque, and debonding were analyzed in relation to dist determination of normality (Shapiro-Wilk test and equality of variance) and, later, the one-way Analysis of Variance (ANOVA) was adopted (Different material groups: G1 to G4), when there was normality of the data, the Tukey post test was adopted for multiple comparisons, when a normal distribution was not identified, the Kruskall-Wallis test and Dunn's or Tukey post-test were used, similarly the specific analysis of the pillar variables (UCLA and Universal Pillar) and systems retainer (Screwed and Cemented). For all tests, a significance level of 5% (α=0.05) was applied. The graphical analysis was considered through a bar graph for the data that presented normality with mean and standard deviation values, and the other analyzes that did not present normality was considered the creation of a boxplot for each comparative group. Implant prostheses using zirconia abutments have gained more and more space, in addition to the in vitro study, a systematic review was performed to compare marginal bone loss and prosthetic complications of rehabilitations using cemented and screwed zirconia abutments. Regarding cemented and screw-retained prostheses, due to conflicting evidence and the presence of many systematic reviews on the subject, an overview of systematic reviews was performed, with the objective of compiling the available information and evaluating the methodological quality of these studies regarding complications present in cemented or screw-retained implant prostheses(AU)


Subject(s)
Dental Prosthesis Retention , Dental Prosthesis, Implant-Supported , Stress, Mechanical , Dental Implants , Dental Abutments , Dental Prosthesis , Dental Marginal Adaptation , Dental Restoration Failure
13.
São José dos Campos; s.n; 2022. 105 p. tab, ilus.
Thesis in Portuguese | LILACS, BBO | ID: biblio-1415240

ABSTRACT

A partir dos avanços da tecnologia CAD/CAM na Odontologia, observa-se a crescente utilização da manufatura aditiva na confecção de peças protéticas. Este trabalho propões a avaliação da acurácia interna e linha de cimentação de endocrowns produzidas através de manufatura aditiva e subtrativa. Para isso foi produzido um modelo mestre preparado para coroa endocrown, o qual foi posteriormente escaneado para desenho e fabricação das restaurações, segundo sua manufatura: aditiva (n=14) e subtrativa (n=14). As endocrowns tiveram sua parte interna escaneadas e através de software de inspeção foram comparadas as diferenças entre o projeto (CAD) e a restauração manufaturada, com a distribuição no interior de cada espécime de 90 pontos de aferição equidistantes. Seus respectivos valores de desvio foram utilizados para o cálculo de um valor eficaz (root mean square - RMS). Além disso, foi mensurada a desadaptação entre as endocrowns e modelo mestre, mediante a técnica da réplica de silicone digital, com aferição da linha de cimentação em pontos padronizados e distribuídos de forma equidistantes na região marginal, axial e pulpar, bem como a mensuração da linha de cimentação absoluta. Os dados da veracidade/acurácia interna passaram por teste de normalidade e comparação estatística pelo teste t student não pareado (α=0,05). Os resultados para veracidade interna RMS (Impresso 49.6032 µm ± 3.8917 e fresado 48.5554µm ± 2.2992) não demonstraram diferença estatística significante entre os grupos (p valor >0.05), entretanto sob avaliação qualitativa em gráfico de cores, houve distorções entre as peças produzidas e o projeto em software CAD, com padrões de distorção distintos segundo o tipo de manufatura. Quanto aos resultados da linha de cimentação, os valores de cada região passaram por teste de normalidade e comparação pelo teste t student não pareado (α=.05). Sem diferença estatística (p valor >0.05) na região marginal (impresso 52.9121 µm ± 10.8946 e fresado 61.8303 µm ± 13.4616) e linha de cimentação absoluta (impresso 84.642µm ± 8.0161 e fresado 89.1016µm ± 10.7006.). Contudo nos resultados da linha de cimentação em região axial (impresso 78.2094µm ± 10.5483 e fresado 95.3686µm ± 9.550), bem como região pulpar (impresso 160.9635µm ± 18.3995 e fresado 131.11µm ± 23.7442), houve diferença estatística significante entre os grupos (p < 0,05). Conclui-se, portanto, com relação aos valores gerais, tais como a linha de cimentação absoluta e veracidade interna, que não houve diferença estatística significante entre as duas manufaturas. Todavia, quanto a avaliações locais da linha de cimentação, o grupo impresso apresentou os melhores resultados em região axial, o grupo fresado em região pulpar e ambos os grupos com resultados semelhantes estatisticamente para região marginal. (AU)


Following the advances in CAD/CAM technology in dentistry and the increasing use of additive manufacturing in prosthetic dentistry, this study proposes the evaluation of the trueness and cementation line adaptation of endocrowns produced through additive and subtractive manufacturing. A master model prepared for endocrown and scanned for design and fabrication of restorations, according to their manufacture type: additive (n=14) and subtractive (n=14). The endocrowns had their internal area scanned and, through an inspection software, the differences between the design (CAD) and the manufactured restoration were compared, based by the distribution in each specimen of 90 equidistant measurement points. And their respective deviation values were used for the calculation of Root Mean Square (RMS). In addition, the misfit between the endocrowns and the master model was measured using the digital silicone replica technique, and the cementation line measured at standardized and equidistant points in marginal, axial, and pulp regions. As well as the measurement of the absolute cementation line. The trueness data underwent a normality test and statistical comparison by the unpaired student t test (α=.05). The results for RMS internal trueness (Printed 49.6032 µm ± 3.8917 and milled 48.5554 µm ± 2.2992) did not show a statistically significant difference between the groups (p value >0.05), however under qualitative evaluation in a color map, there are distortions between the crowns produced and the design in CAD software, following different patterns according to the manufacture type. As for the results of the cementation line, the data of each region underwent a normality test and comparison by the unpaired t student test (α=.05). No statistical difference (p value >0.05) in the marginal region (printed 52.9121 µm ± 10.8946 and milled 61.8303 µm ± 13.4616) and absolute cementation line (printed 84.642µm ± 8.0161 and milled 89.1016 µm ± 10.7006.) were observed. However, in the results of the cementation line at the axial region (printed 78.2094µm ± 10.5483 and milled 95.3686µm ± 9.550), as well the pulp region (printed 160.9635µm ± 18.3995 and milled 131.11µm ± 23.7442), there was a statistically significant difference between the groups (p < 0.05). This study concludes that in relation to the global values, such as the absolute cementation line and internal trueness, that there was no statistically significant difference between the two manufacturing types. However, regarding the local assessments of the cementation line, the printed group presented the best results in the axial region, the milled group in the pulp region, and both groups with statistically similar results for the marginal region. (AU)


Subject(s)
Dental Prosthesis , Computer-Aided Design , Dental Marginal Adaptation , Printing, Three-Dimensional
14.
Article in English | LILACS, BBO | ID: biblio-1365234

ABSTRACT

ABSTRACT Objective To evaluate the marginal adaptation of computer-aided designing and computer-aided machining (CAD/CAM) fabricated cobalt-chromium and zirconium-oxide-based ceramic crowns compared to those produced by a conventional method. Material and Methods The study consists of three groups; 45 crowns fabricated from cobalt-chromium (CAD-CoCr) and 45 crowns manufactured from zirconium CAD/CAM technology (CAD-Z), and 45 control (C) which consists of conventional metal-ceramic crowns. The marginal discrepancies in vertical dimensions were assessed utilizing a microscope in four surfaces (mesial, distal, vestibular, and oral) for each crown. On completion of the microscopic evaluation, multivariate analysis of variance (MANOVA) was used to study the difference in the four surfaces, considered altogether. Two-way ANOVA revealed the effect of three systems used for gap measurements of each landmark. The differences observed were considered significant at p<0.05. Results There were no differences in the four surfaces revealed by АNOVА in the three groups when considered altogether. Two-way ANOVA of each surface discovered no differences among all groups as well. Conclusion The CAD/CAM crowns revealed a comparable and satisfactory marginal adaptation compared to conventional metal-ceramic crowns.


Subject(s)
Zirconium , Chromium Alloys , Dental Prosthesis/instrumentation , Crowns , Dental Porcelain , In Vitro Techniques , Analysis of Variance , Metal Ceramic Alloys , Computer-Aided Design , Dental Marginal Adaptation , India
15.
Braz. j. oral sci ; 20: e214873, jan.-dez. 2021. ilus
Article in English | BBO, LILACS | ID: biblio-1254742

ABSTRACT

Aim: To compare the marginal fit of lithium disilicate CAD/CAM crowns and heat-pressed crowns fabricated using milled wax patterns, and evaluate its effect on stress distribution in implantsupported rehabilitation. Methods: A CAD model of a mandibular first molar was designed, and 16 lithium disilicate crowns (8/group) were obtained. The crown-prosthetic abutment set was evaluated in a scanning electron microscopy. The mean misfit for each group was recorded and evaluated using Student's t-test. For in silico analysis, a virtual cement thickness was designed for the two misfit values found previously, and the CAD model was assembled on an implant-abutment set. A load of 100 N was applied at 30° on the central fossa, and the equivalent stress was calculated for the crown, titanium components, bone, and resin cement layer. Results: The CAD/CAM group presented a significantly (p=0.0068) higher misfit (64.99±18.73 µm) than the heat-pressed group (37.64±15.66 µm). In silico results showed that the heat-pressed group presented a decrease in stress concentration of 61% in the crown and 21% in the cement. In addition, a decrease of 14.5% and an increase of 7.8% in the stress for the prosthetic abutment and implant, respectively, was recorded. For the cortical and cancellous bone, a slight increase in stress occurred with an increase in the cement layer thickness of 5.9% and 5.7%, respectively. Conclusion: The milling of wax patterns for subsequent inclusion and obtaining heat-pressed crowns is an option to obtain restorations with an excellent marginal fit and better stress distribution throughout the implant-abutment set


Subject(s)
Microscopy, Electron, Scanning , Computer-Aided Design , Dental Marginal Adaptation , Dental Prosthesis, Implant-Supported , Finite Element Analysis , Dental Materials
16.
J. oral res. (Impresa) ; 10(3): 1-10, jun. 30, 2021. ilus
Article in English | LILACS | ID: biblio-1391196

ABSTRACT

Background: The aim of this study was to elaborate a randomized clinical trial protocol to evaluate the effectiveness of class I restorations in resin-modified glass ionomer cement (RMGIC) and bulk-fill resin in primary molars with untreated early childhood caries in toddlers. Material and Methods: A total of 59 toddlers up to 36 months old with at least two primary molar teeth with untreated dental caries of single surface on different sides of the mouth will be selected at the Pediatric Dentistry Clinics of the Faculty of Dentistry at Federal University of Minas Gerais (UFMG), Brazil. Teeth with untreated dental caries in the left and right sides of each patient's mouth will be randomly distributed into 2 groups: Group 1 (Control): encapsulated RMGIC restoration with Riva light cure (SDI, Florida, USA) and Group 2 (Test): Filtek bulk-fill composite resin restoration (3M/ESPE, St. Paul, USA) with universal single bond adhesive system (3M/ESPE, St. Paul, USA). A single trained dentist will perform all restorative procedures. The restorations will be evaluated after 1, 6, 12, 18 and 24 months by two trained and calibrated examiners. Cost-efficacy analysis will be carried out. Kaplan-Meier survival analysis, Log-rank test, Cox regression, Poisson regression analysis, Mann-Whitney test or Kruskal-Wallis will be performed to analyze data. Conclusion: The protocol will make it possible to determine the most efficacy material for the restoration of cavities in cavities in primary molars of toddlers.


Antecedentes: El objetivo de este estudio fue elaborar un protocolo de ensayo clínico aleatorizado para evaluar la efectividad de las restauraciones de clase I en cemento de ionómero de vidrio modificado con resina (RMGIC) y resina bulk-fill en molares primarios con caries de la primera infancia no tratadas en niños preescolares. Material y Métodos: Un total de 59 niños de hasta 36 meses de edad con al menos dos molares temporales con caries no tratada de superficie única en diferentes lados de la boca serán seleccionados en las Clínicas de Odontología Pediátrica de la Facultad de Odontología de la Universidad Federal de Minas Gerais (UFMG), Brasil. Los dientes con caries no tratada en los lados izquierdo y derecho de la boca de cada paciente se distribuirán aleatoriamente en 2 grupos: Grupo 1 (Control): restauración RMGIC encapsulada con fotopolimerización Riva (SDI, Florida, EE. UU.) Y Grupo 2 (Prueba): Restauración de resina compuesta bulk-fill Filtek (3M / ESPE, St. Paul, EE. UU.) con sistema adhesivo de unión simple universal (3M / ESPE, St. Paul, EE. UU.). Un solo dentista capacitado realizará todos los procedimientos de restauración. Las restauraciones serán evaluadas después de 1, 6, 12, 18 y 24 meses por dos examinadores capacitados y calibrados. Se llevará a cabo un análisis de coste-eficacia. Se realizarán análisis de supervivencia de Kaplan-Meier, prueba de rango logarítmico, regresión de Cox, análisis de regresión de Poisson, prueba de Mann-Whitney o Kruskal-Wallis para analizar los datos. Conclusión: El protocolo permitirá determinar el material más eficaz para la restauración de caries en molares temporales de niños preescolares.


Subject(s)
Humans , Male , Female , Infant, Newborn , Infant , Child, Preschool , Composite Resins/therapeutic use , Glass Ionomer Cements/therapeutic use , Brazil/epidemiology , Pediatric Dentistry , Dental Marginal Adaptation , Dental Caries , Dental Restoration, Permanent/methods , Molar
17.
Braz. dent. sci ; 24(3): 1-13, 2021. tab, ilus, graf
Article in English | LILACS, BBO | ID: biblio-1280983

ABSTRACT

Objective: The purpose of this study was to evaluate and compare gross fracture, patient satisfaction and marginal adaptation of anterior endocrowns restoring endodontically treated anterior teeth fabricated from IPS e.max press and CERASMART hybrid ceramics. Material and Methods: A total of 24 patients were selected to receive an aesthetic endocrown for an upper tooth in the aesthetic zone (central incisor, lateral and canine).The 24 patients were divided into two groups (n= 12 each), where Group 1, the control group, received an IPS e.max press anterior endocrown and Group 2, theintervention group, received a CERASMART anterior endocrown. After cementation all patients were followed up at 3, 6, 9 and 12 months. During each follow-up examination, United States Public Health Servicecriteria were adopted for clinical evaluation to score margin integrity and gross fracture. Questionnaires were also used to evaluate the patients' satisfaction and potential postoperative discomfort. The X2 or Fisher's Exact test were used to compare qualitative variables in the two groups and Friedman's test was used to study the changes over time within each group. The significance level was set at P≤ 0.05. Results: With regard to gross fracture and marginal integrity, there was no statistically significant difference at any time interval between IPS e.max press and CERASMART endocrowns. All patients reported being satisfied with their restorations until the end of the follow-up period. Conclusions: CERASMART anterior endocrowns provided a promising treatment modality compared to IPS e.max press anterior endocrowns. (AU)


Objetivo: o objetivo deste estudo foi avaliar e comparar a fratura grosseira, a satisfação do paciente e a adaptação marginal de endocrowns em dentes anteriores tratados endodonticamente, fabricados a partir de IPS e.max press e cerâmicas híbridas CERASMART. Material e Métodos: Um total de 24 pacientes foi selecionado para receber endocrown em um dente superior na zona estética (incisivo central, lateral e canino). Os 24 pacientes foram divididos em dois grupos (n = 12 cada), onde o Grupo 1, o grupo controle, recebeu uma endocrown anterior IPS e.max press e o Grupo 2, o grupo de intervenção, recebeu uma endocrown anterior CERASMART. Após a cimentação, todos os pacientes foram acompanhados em 3, 6, 9 e 12 meses. Durante cada exame de acompanhamento, os critérios do Serviço de Saúde Pública dos Estados Unidos foram adotados para avaliação clínica para pontuar integridade de margem e fratura grosseira. Questionários também foram usados para avaliar a satisfação dos pacientes e potencial desconforto pós-operatório. O teste X2 ou teste de Fisher foi usado para comparar as variáveis qualitativas nos dois grupos, e o teste de Friedman foi usado para estudar as mudanças ao longo do tempo dentro de cada grupo. O nível de significância foi estabelecido em P≤ 0,05. Resultados: Com relação à fratura grosseira e integridade marginal, não houve diferença estatisticamente significativa em qualquer intervalo de tempo entre os endocrowns IPS e.max press e CERASMART. Todos os pacientes relataram estar satisfeitos com suas restaurações até o final do período de acompanhamento. Conclusão: os endocrowns anteriores CERASMART proporcionaram uma modalidade de tratamento promissora em comparação com os endocrowns anteriores IPS e.max press. (AU)


Subject(s)
Humans , Patient Satisfaction , Dental Marginal Adaptation , Tooth, Nonvital
18.
Braz. dent. sci ; 24(3): 1-14, 2021. tab, ilus
Article in English | BBO, LILACS | ID: biblio-1282177

ABSTRACT

Objective: To evaluate fracture resistance and survival rate of IPS Empress CAD versus Polished Celtra Duo ceramic laminate veneers. Material and Methods:Thirty-six ceramic laminate veneers were fabricated for maxillary anterior teeth. The patients were divided into two groups according to the material Group 1(control group) fabricated from IPS Empress CAD laminate veneers and group 2 (intervention group) fabricated from Polished Celtra Duo laminate veneers. Standardized the same preparation with butt joint design and chamfer finish line located supra gingival were performed for all the teeth. The fabrication of the veneers was performed using Cad\Cam (Ceramill motion) machine, with software (Exocad). The veneers surfaces were treated and silanated according to the manufacture instruction of each ceramic and enamel surfaces were etched where total etch adhesive protocol was obeyed using BISCO. Follow up sessions were done every two months up to one year for each patient using dental probe and operator vision to evaluate the fracture, survival rate, marginal adaptation, sensitivity and caries. according to USPHS criteria (United States Public Health Service). This was performed by an experienced, blinded investigator. Results: Fracture resistance, marginal adaptation, retention, caries and sensitivity were evaluated according to the criteria of USPHS and we found there is no significant difference as both groups scaled zero score. Conclusion: Both IPS Empress Cad and Polished Celtra Duo laminate veneers revealed successful clinical performance in terms of fracture resistance, marginal adaptation, retention, and sensitivity after one year follow up period (AU)


Objetivo: Avaliar a resistência à fratura e a taxa de sobrevivência de laminados de cerâmica IPS Empress CAD versus Celtra Duo polidos. Material e Métodos: Trinta e seis facetas cerâmicas laminadas foram confeccionadas para dentes anteriores superiores. Os pacientes foram divididos em dois grupos de acordo com o material Grupo 1 (grupo controle) confeccionado com laminados IPS Empress CAD e grupo 2 (grupo intervenção) confeccionado com laminados Celtra Duo polidos. A mesma forma de preparo e acabamento de chanfro localizado supra-gengival padronizados foram realizados para todos os dentes. A confecção das facetas foi realizada em máquina Cad \ Cam (Ceramill motion), com software (Exocad). As superfícies laminadas foram tratadas e silanizadas de acordo com as instruções do fabricante de cada cerâmica e as superfícies de esmalte foram condicionadas seguindo o protocolo adesivo de condicionamento ácido total com BISCO. Sessões de acompanhamento foram realizadas a cada dois meses durante um ano para cada paciente usando sonda exploradora e visão do operador para avaliar a fratura, taxa de sobrevivência, adaptação marginal, sensibilidade e cárie; de acordo com os critérios USPHS (Serviço de Saúde Pública dos Estados Unidos). Isso foi realizado por um investigador experiente e cego. Resultados: a resistência à fratura, adaptação marginal, retenção, cárie e sensibilidade foram avaliadas de acordo com os critérios da USPHS e não encontramos diferença significativa, pois ambos os grupos escalonaram pontuação zero. Conclusão: As facetas laminadas IPS Empress Cad e Celtra Duo polido revelaram desempenho clínico bem-sucedido em termos de resistência à fratura, adaptação marginal, retenção e sensibilidade após um período de acompanhamento de um ano. (AU)


Subject(s)
Humans , Dental Marginal Adaptation , Dental Caries , Dental Veneers , Dentin Sensitivity , Flexural Strength
19.
Rev. Ateneo Argent. Odontol ; 64(1): 77-82, 2021.
Article in Spanish | LILACS | ID: biblio-1252984

ABSTRACT

A pesar de los avances e innovaciones de los materiales dentales, la microfiltración marginal y la contracción durante la polimerización continúan siendo una de las causas principales del fracaso de los tratamientos en odontología restauradora. Un sellado marginal correcto será posible cuando las fuerzas de adhesión superen las fuerzas generadas por la contracción de polimerización y las fuerzas generadas por los cambios dimensionales térmicos posteriores a la polimerización, por lo que investigaciones previas demostraron que estas limitaciones pueden ser superadas con el uso de resinas Bulk Fill como material de relleno de cavidades extensas y profundas de dientes posteriores. Estas resinas. de relleno masivo, están recibiendo atención, principalmente porque se pueden colocar, a diferencia de las resinas convencionales, en incrementos de 4 mm sin afectar la contracción de la polimerización, la adaptación de la cavidad o el grado de conversión. El objetivo de la presente revisión bibliográfica es describir la contracción de polimerización y la consecuente filtración marginal que sufren las resinas compuestas para el sector posterior Bulk Fill con base de datos de la literatura (AU)


Despite advances and innovations in dental materials, marginal microfiltration and shrinkage during polymerization continue to be one of the main causes of treatment failure in Restorative Dentistry. A correct marginal seal will be possible when the adhesion forces exceed the forces generated by polymerization contraction and the forces generated by post-polymerization thermal dimensional changes, for which previous research has shown that these limitations can be overcome with the use of Bulk Fill resins as filling material for large and deep posterior tooth cavities, these massive filling resins are receiving attention mainly because they can be placed, unlike conventional resins, in 4 mm increments without affecting polymerization shrinkage. , cavity adaptation or degree of conversion. The objective of the present bibliographic review is to describe the polymerization contraction and consequent marginal filtration suffered by Composite Resins for the Bulk Fill posterior sector with a literature database (AU)


Subject(s)
Humans , Dental Marginal Adaptation , Composite Resins , Dental Leakage , Polymerization , Materials Testing , Dental Cavity Preparation , Dental Restoration, Permanent/instrumentation
20.
Braz. dent. sci ; 24(1): 1-8, 2021. tab, ilus
Article in English | BBO, LILACS | ID: biblio-1145442

ABSTRACT

Objetivo: Estudos demostraram que a zircônia monolítica um dos materiais restauradores desenvolvidos recentemente, resolveu vários problemas de restauração de zircônia. Portanto, a precisão marginal e o ajuste interno são necessários para o sucesso clinico e para a qualidade da restauração, e o espaço do cimento pode influenciar o ajuste marginal. Assim, o presente estudo teve como objetivo investigar os efeitos da espessura do cimento e o tipo de restauração na discrepância marginal. Material e métodos: foram usadas para fabricação de coroa total. Dois tipos de materiais incluindo Zirconia monolítica (Zolid) e Sintron foram usadas para produzir a coroa total. As amostras de cada grupo foram digitalizadas em laboratório dentário por um scanner 3D, projetadas e acessadas usando CAD-CAM. As amostras foram divididas em quatro grupos de cinco com espaço de 30 e 50 mícrons de cimento. Para avaliar a discrepância marginal, as coroas foram colocadas em seus respectivos dentes sem o uso de qualquer intermediário e examinados em micro-CT. Os dados foram avaliados pelo software SPSS. Resultados: Descobriu-se que a discrepância marginal do Sintron é maior que a discrepância da zircônia monolítica. Na verdade, a zircônia monolítica com espaço de 50 µm de cimento exibiu uma menor discrepância marginal, e o espaço de cimento do Sintron não influenciou significantemente na discrepância marginal. Conclusão: Concluiu-se que os tipos de material e o espaço do cimento influencia na discrepância marginal da restauração construída pelo fluxo digital (AU)


Objective: Studies demonstrated that as one of then ewly developed restorative materials, monolithic zirconia resolved several issues of zirconia restoration. Therefore, marginal accuracy and internal fit are necessary for clinical success and quality of restorations, and cement space may influence the marginal fit. Thus, the present research aimed to investigate the effects of the cement thickness and kind of restoration on the marginal discrepancy. Material and methods: In this study, 20 maxillary left first molars, prepared by DRSK Co., were used to fabricate a full crown. Two types of material included monolithic zirconia (Zolid) and Sintron were used to make a full crown. Samples from each group were scanned by dental laboratory 3D scanner and designed and processed using CAD-CAM. The samples were divided into four groups of five with 30-and 50- µm cement spaces. In order to assess the vertical marginal discrepancy, the crowns were fittedon their respective teeth without using any mediator and examined by a micro-CT scanner. Data were analyzed by SPSS software. Results: It has been found that marginal discrepancy in Sintron is higher than the discrepancy of monolithic zirconia. In fact, monolithic zirconia with 50-micron cement space exhibited the least marginal discrepancy and the cement space in Sintron did not significantly influence the marginal discrepancy. Conclusion: It has been concluded that the material kinds and cement space influence the restoration marginal discrepancy constructed by digital workflow (AU)


Subject(s)
Dental Marginal Adaptation , Dental Cements , X-Ray Microtomography
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