Faculdade São Leopoldo Mandic, Instituto de Pesquisas São Leopoldo Mandic, Departamento de Odontologia Restauradora, Campinas, Brasil.
University of Florida, Health Faculty Dental Practice, Operative Division, Gainesville, USA.
Acta Odontol Latinoam. 2021 Aug 1;34(2):173-182. doi: 10.54589/aol.34/2/173.
The aim of this study was to compare low- and high-viscosity bulk-fill composites for Knoop microhardness (KHN), microtensile bond strength (MTBS) to dentin in occlusal cavities, and fracture strength (FS) in molars with mesialocclusal- distal restoration. Disk-shaped samples with different thicknesses (2 or 4 mm) of low-viscosity (SDR Flow, Dentsply) and high-viscosity bulk-fill composites (Filtek BulkFill, 3M ESPE; and Tetric-N Ceram Bulk Fill, Ivoclar Vivadent) were prepared for top and bottom KHN analysis (n=10). MTBS to dentin and fracture pattern was evaluated in human molars with occlusal cavities restored with (n=10): conventional nanocomposite (Z350XT, 3M ESPE), low-viscosity (Filtek Bulk-fill Flow, 3M ESPE) or high-viscosity bulk-fill composites (Filtek BulkFill). The FS and fracture pattern of human molar with mesial-occlusal-distal restorations submitted or not to thermomechanical cycling were investigated (n=10) using: intact tooth (control), and restoration based on conventional microhybrid composite (Z250, 3M ESPE), low-viscosity (SDR Flow) or high-viscosity bulk-fill composites (Filtek BulkFill). The data were submitted to split-plot ANOVA (KHN), one-way ANOVA (MTBS), two-way ANOVA (FS) followed by Tukey's test (α=0.05). For KHN, there was no significant difference for the resin composites between the top and bottom. For MTBS, no significant differences among the materials were detected; however, the low-viscosity composite presented lower frequency of adhesive failures. For FS, there was no significant difference between composites and intact tooth regardless of thermomechanical cycling. Low- and high-viscosity bulk-fill composites have comparable microhardness and microtensile bond strength when used in occlusal restorations. Likewise, the bulk-fill composites present similar fracture strength in molars with mesio-occlusal-distal restorations.
本研究旨在比较低粘度和高粘度块状充填复合材料的维氏硬度（KHN）、牙本质微拉伸粘结强度（MTBS）、颊舌向窝洞的断裂强度（FS），以及近中-远中修复的磨牙。对于上下 KHN 分析（n=10），制备了不同厚度（2 或 4mm）的低粘度（SDR Flow，Dentsply）和高粘度块状充填复合材料（Filtek BulkFill，3M ESPE；和 Tetric-N Ceram Bulk Fill，Ivoclar Vivadent）的圆盘形样本。在颊舌向窝洞修复的人磨牙中评估了 MTBS 到牙本质和断裂模式（n=10）：传统纳米复合材料（Z350XT，3M ESPE）、低粘度（Filtek Bulk-fill Flow，3M ESPE）或高粘度块状充填复合材料（Filtek BulkFill）。使用未经或经热机械循环处理的人磨牙近中-颊舌-远中修复体的 FS 和断裂模式进行了研究（n=10）：完整牙（对照）、基于传统微混合复合材料（Z250，3M ESPE）的修复体、低粘度（SDR Flow）或高粘度块状充填复合材料（Filtek BulkFill）。数据进行了分割区组方差分析（KHN）、单向方差分析（MTBS）、双向方差分析（FS），然后进行 Tukey 检验（α=0.05）。对于 KHN，在顶部和底部的树脂复合材料之间没有显著差异。对于 MTBS，未检测到材料之间的显著差异；然而，低粘度复合材料的黏附性失败频率较低。对于 FS，无论是否经过热机械循环，复合材料与完整牙之间均无显著差异。低粘度和高粘度块状充填复合材料在颊舌向窝洞修复中具有相当的显微硬度和微拉伸粘结强度。同样，块状充填复合材料在近中-远中修复的磨牙中具有相似的断裂强度。
