Duarte Júlio César Lemos, Costa Ana Rosa, Veríssimo Crisnicaw, Duarte Renata Webster, Calabrez Filho Saturnino, Spohr Ana Maria, Borges Gilberto Antonio, Correr-Sobrinho Lourenço
Department of Restorative Dentistry, Dental Materials, UNIUBE - Universidade de Uberaba, Uberaba, MG, Brazil.
Department of Restorative Dentistry, Dental Materials Division, Piracicaba Dental School, UNICAMP - Universidade Estadual de Campinas, Piracicaba, SP, Brazil.
Braz Dent J. 2020 Sep-Oct;31(5):532-539. doi: 10.1590/0103-6440202003338.
The aim was to evaluate the microtensile bond strength (mTBS) to dentin and interfacial stress in a class II cavity restored with bulk-fill or conventional composite resins and the margin interfaces. Vertical slot class II cavities in the mesial face, with the gingival end in dentin, were prepared in 72 third molars, being divided into groups (n=24): G1-Tetric N-Ceram; G2-Tetric N-Ceram Bulk-Fill; G3-SonicFill. Clearfil SE Bond adhesive system was used in all groups. Half of the teeth in each group (n=12) were submitted to thermo-mechanical cycling (TMC). Restored teeth (n=9) were cut perpendicular to obtain beams, which were submitted to a mTBS test in an EMIC machine. The cervical margins in dentin of the restored teeth (n=3) were assessed using SEM through epoxy resin replicas as well as the section of the restoration. Interfacial stresses after load application were calculated by 2D finite element analysis. The mTBS means-MPa followed by different letters represent statistical difference by ANOVA and Games-Howell's test (p<0.05): Without TMC: G1-15.68±6.10a; G2-10.08±5.21ab; G3-7.98±3.76b. With TMC: G1-9.70±5.52a; G2-5.79±1.42a; G3-4.37±1.87a. Interfacial stress (MPa) was 4.4 for SonicFill, 3.9 for Tetric N-Ceram, and 3.5 for Tetric N-Ceram Bulk-Fill. SEM images showed continuous margins for all composite resin restorations. It was possible to conclude that SonicFill obtained a slightly higher interfacial stress and lower bond strength to dentin in comparison with Tetric N-Ceram and Tetric N-Ceram Bulk-Fill. Continuous margin interfaces were obtained for Tetric N-Ceram, Tetric N-Ceram Bulk-Fill, and SonicFill. However, voids were observed in the SonicFill restorations.
目的是评估用大块充填或传统复合树脂修复的Ⅱ类洞及其边缘界面与牙本质的微拉伸粘结强度（mTBS）和界面应力。在72颗第三磨牙的近中面制备垂直槽Ⅱ类洞，龈端位于牙本质内，将其分为几组（n = 24）：G1-Tetric N-Ceram；G2-Tetric N-Ceram Bulk-Fill；G3-SonicFill。所有组均使用Clearfil SE Bond粘结系统。每组中一半的牙齿（n = 12）进行热机械循环（TMC）。将修复后的牙齿（n = 9）垂直切割以获得梁，然后在EMIC机器上对其进行mTBS测试。使用扫描电子显微镜（SEM）通过环氧树脂复制品以及修复体切片评估修复后牙齿（n = 3）牙本质中的颈部边缘。通过二维有限元分析计算加载后的界面应力。mTBS平均值（MPa）后接不同字母表示通过方差分析（ANOVA）和Games-Howell检验存在统计学差异（p<0.05）：未进行TMC时：G1-15.68±6.10a；G2-10.08±5.21ab；G3-7.98±3.76b。进行TMC时：G1-9.70±5.52a；G2-5.79±1.42a；G3-4.37±1.87a。SonicFill的界面应力（MPa）为4.4，Tetric N-Ceram为3.9，Tetric N-Ceram Bulk-Fill为3.5。SEM图像显示所有复合树脂修复体的边缘连续。可以得出结论，与Tetric N-Ceram和Tetric N-Ceram Bulk-Fill相比，SonicFill获得的界面应力略高，与牙本质的粘结强度较低。Tetric N-Ceram、Tetric N-Ceram Bulk-Fill和SonicFill均获得了连续的边缘界面。然而，在SonicFill修复体中观察到有空隙。
