Fracture strength of teeth restored with milled ultrathin occlusal veneers made of polymer-infiltrated ceramic.

The purpose was to evaluate, in vitro, the fracture strength of teeth restored with 0.3- or 0.6-mm-thick occlusal veneers made of Vita Enamic® bonded to enamel or dentin. Fifty third molars were allocated into five groups (n=10): Group C - control (sound teeth); Group 0.3E - 0.3-mm-thick occlusal veneers bonded to enamel; Group 0.6E - 0.6-mm-thick occlusal veneers bonded to enamel; Group 0.3D - 0.3-mm-thick occlusal veneers bonded to dentin; Group 0.6D - 0.6-mm-thick occlusal veneers bonded to dentin. After luting with Single Bond Universal and Filtek Z-100, the samples were subjected to fracture strength test in a universal testing machine. The fractures were classified as irreparable and reparable. Data were analyzed with 2-way and 1-way ANOVA (α=.05) followed by Tukey's test. The teeth restored with 0.3-mm-thick occlusal veneers (2658 N) achieved significantly higher fracture strength compared to the teeth restored with 0.6-mm-thick occlusal veneers (2070 N) (p=0.017). The teeth restored with occlusal veneers bonded to enamel (2648 N) had significantly higher fracture strength compared to the teeth restored with occlusal veneers bonded to dentin (2049 N) (p=0.015). Group C (3355 N) and Group 0.3E (2965 N) did not differ significantly from each other, being the fracture strength significantly higher than the other groups (p<0.05). The fractures were predominantly reparable. The teeth restored with 0.3-mm-thick occlusal veneers achieved higher fracture strength compared to the teeth restored with 0.6-mm-thick occlusal veneers. The supporting substrate influenced the fracture strength, which was higher for the teeth restored with occlusal veneers bonded to enamel.

Fracture strength of teeth restored with milled ultrathin occlusal veneers made of polymer-infiltrated ceramic

Abstract The purpose was to evaluate, in vitro, the fracture strength of teeth restored with 0.3- or 0.6-mm-thick occlusal veneers made of Vita Enamic® bonded to enamel or dentin. Fifty third molars were allocated into five groups (n=10): Group C - control (sound teeth); Group 0.3E - 0.3-mm-thick occlusal veneers bonded to enamel; Group 0.6E - 0.6-mm-thick occlusal veneers bonded to enamel; Group 0.3D - 0.3-mm-thick occlusal veneers bonded to dentin; Group 0.6D - 0.6-mm-thick occlusal veneers bonded to dentin. After luting with Single Bond Universal and Filtek Z-100, the samples were subjected to fracture strength test in a universal testing machine. The fractures were classified as irreparable and reparable. Data were analyzed with 2-way and 1-way ANOVA (α=.05) followed by Tukey's test. The teeth restored with 0.3-mm-thick occlusal veneers (2658 N) achieved significantly higher fracture strength compared to the teeth restored with 0.6-mm-thick occlusal veneers (2070 N) (p=0.017). The teeth restored with occlusal veneers bonded to enamel (2648 N) had significantly higher fracture strength compared to the teeth restored with occlusal veneers bonded to dentin (2049 N) (p=0.015). Group C (3355 N) and Group 0.3E (2965 N) did not differ significantly from each other, being the fracture strength significantly higher than the other groups (p<0.05). The fractures were predominantly reparable. The teeth restored with 0.3-mm-thick occlusal veneers achieved higher fracture strength compared to the teeth restored with 0.6-mm-thick occlusal veneers. The supporting substrate influenced the fracture strength, which was higher for the teeth restored with occlusal veneers bonded to enamel.

Resumo O objetivo foi avaliar, in vitro, a resistência à fratura de dentes restaurados com facetas oclusais de Vita Enamic® com 0,3 ou o,6 mm de espessura e cimentadas em esmalte ou dentina. Cinquenta terceiros molares foram distribuídos em grupos (n=10): Grupo C-controle (dentes hígidos); Grupo 0,3E - facetas oclusais com 0,3 mm de espessura cimentados em esmalte; Grupo 0,6E - facetas com 0,6 mm de espessura cimentados em esmalte; Grupo 0,3D - facetas com 0,3 mm de espessura cimentados em dentina; Grupo 0,6D - facetas com 0,6 mm de espessura cimentados em dentina. Após cimentação com Single Bond Universal Filtek Z-100, as amostras foram submetidas ao teste de resistência à fratura em máquina de ensaio universal. As falhas foram classificadas em reparáveis e irreparáveis. Os resultados foram analisados pelo teste ANOVA de duas vias e uma via (α=0,05) seguido do teste de Tukey. Os dentes restaurados com facetas oclusais com 0,3 mm de espessura (2658 N) obtiveram resistência à fratura estatisticamente superior aos dentes restaurados com facetas com 0,6 mm (2070 N) (p=0.017). Os dentes restaurados com facetas cimentadas em esmalte (2648 N) tiveram resistência à fratura estatisticamente maior comparada aos dentes restaurados com facetas cimentadas em dentina (2049 N) (p=0.015). Grupo C (3355 N) e Grupo 0,3E (2965 N) não diferiram estatisticamente entre si, tendo resistência à fratura estatisticamente superior aos outros grupos (p<0.05). As fraturas foram predominantemente reparáveis. Os dentes restaurados com facetas oclusais com 0,3 mm de espessura apresentaram maior resistência à fratura comparada aos dentes restaurados com facetas com 0,6 mm. O substrato influenciou a resistência à fratura dos dentes restaurados com facetas oclusais, sendo maior quando cimentadas ao esmalte.

Grading Class I Preparations in Preclinical Dental Education: E4D Compare Software vs. the Traditional Standard.

The aim of this study was to compare the effectiveness of a novel assessment software system with the traditional grading protocol used in the University of Texas School of Dentistry at Houston operative dentistry preclinical curriculum. In the study, conducted in 2016, 98 Class I preparations were evaluated both traditionally and digitally by two teams of calibrated preclinical faculty members (two evaluators for each team). Scores from each faculty pair were averaged for the traditional and the digital grading systems, and the scores for the two grading systems were compared. The analysis found no significant difference between the two grading systems with respect to isthmus width (p=0.073) and remaining marginal ridge (p=0.5841), but there was a significant difference with respect to pulpal floor depth assessment (p<0.0001). The data suggested that both grading techniques can be used with repeatable confidence for two out of three grading criteria: isthmus width and remaining marginal ridge. In addition, the software offers a self-assessment tool for students to perfect their psychomotor skills while promoting independence and immediate feedback.

Push-out bond strength of a new endodontic obturation system (Resilon/Epiphany).

Endodontic sealers should demonstrate adhesive properties to dentin to reach the objectives of the obturation of the canal space and seal the canal space both apically and coronally, thus decreasing the chance of endodontic treatment failure. Adhesion to dentin with bonding to the tooth structure in the canal may provide greater resistance to tooth fracture and greater clinical longevity of an endodontically treated tooth. In this study, human single-canal canines were endodontically treated and obturated with two different endodontic obturation systems (Epiphany/Resilon system and gutta-percha/AH 26). Thirty roots (divided into two groups) were horizontally sliced for a push-out strength test, which was performed from apical to coronal in the universal testing machine. Differences in push-out bond strength between the two different material systems were obtained using repeated measures analysis of variance on ranks. Gutta-percha had significantly higher push-out bond strength than Epiphany (p<0.0001).