Purpose

To investigate the mechanical performance and fracture behavior of endocrown restorations prepared using different composite materials and following a direct technique. Methods: Sound molars were cut at 2 mm above the cementoenamel junction, endodontically treated, and allocated according to the type of restoration (n = 7): without post (endocrowns) or with post (post-retained restorations). Endocrowns were fabricated with conventional composite (Filtek Z350); bulk fill composite (Filtek Bulk Fill); conventional composite modeled using resin adhesives (SBMP: Scotchbond Multipurpose Adhesive; or SBU: Scotchbond Universal Adhesive); and lithium disilicate ceramic (E.max; Positive control). The post-retained restorations were fabricated with glass-fiber post combined with conventional or bulk fill composites. All restorations were bonded following an etch-and-rise adhesive approach or self-adhesive resin cement. The teeth were submitted to fatigue (Byocycle) and compression (EMIC DL500) testing at a crosshead speed of 1 mm/min. Data were analyzed with ANOVA and Tukey (p < 0.05) and Weibull analysis was carried out in order to evaluate the reliability of restorations. Results: The bulk-fill-based endocrown showed a stronger performance than the control. The presence of SBMP or the use of bulk-fill composite resulted in the occurrence of less aggressive fractures than the other restorative systems. Endocrowns bonded directly to the tooth seemed to produce similar fracture strength properties as compared to endocrowns bonded using self-adhesive resin cementation. The bulk-fill-based endocrown showed the greatest reliability of study. Conclusion: Resin-based restorative materials seem to be interesting alternative options to fabricate large dental restorations in lieu of the more traditionally used glass ceramics or root canal post systems.

中文翻译：

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哪种材料可以为直接内冠修复提供更好的机械性能？

目的

调查使用不同的复合材料并遵循直接技术制备的内冠修复体的力学性能和断裂行为。方法：在牙釉质接合处上方2毫米处切开磨牙，进行牙髓治疗，并根据修复体的类型（n = 7）进行分配：无牙柱（内分泌）或有牙柱（保留后的牙体）。用传统的复合材料（Filtek Z350）制造内腔。散装填充复合材料（Filtek散装填充）; 使用树脂粘合剂（SBMP：Scotchbond通用粘合剂；或SBU：Scotchbond通用粘合剂）建模的常规复合材料；和二硅酸锂陶瓷（E.max；阳性对照）。保留后的修复体是由玻璃纤维桩与常规或散装填充复合材料制成的。所有修复体均采用蚀刻和上升粘合方法或自粘合树脂胶结剂进行粘合。以1 mm / min的十字头速度对牙齿进行疲劳（Byocycle）和压缩（EMIC DL500）测试。数据用方差分析和Tukey（p <0.05）进行分析，并进行Weibull分析以评估修复体的可靠性。结果：基于散装填充的内冠显示出比对照更强的性能。与其他修复系统相比，SBMP的存在或大块填充复合材料的使用导致了较不活跃的骨折的发生。与使用自粘树脂胶结法粘结的内冠相比，直接粘结在牙齿上的内胚层似乎产生了类似的断裂强度性能。基于散装填充的内冠显示出最大的研究可靠性。结论：以树脂为基础的修复材料似乎是制造大型牙齿修复体的有趣替代选择，以代替更传统使用的玻璃陶瓷或牙根管系统。