Santana Ivone L, Lodovici Edméa, Matos Jivaldo R, Medeiros Igor S, Miyazaki Caroline L, Rodrigues-Filho Leonardo E
Department of Restorative Dentistry, Federal University of Maranhão, São Luís, MA, Brazil.
Braz Dent J. 2009;20(3):205-10. doi: 10.1590/s0103-64402009000300006.
The aim of this study was to verify the influence of an experimental heat treatment (170 masculineC/10 min) using a casting furnace on the mechanical properties (hardness and flexural strength) of 2 commercial direct resin composites (TPH Spectrum and Filtek P60) compared to a commercial indirect resin system (BelleGlass). Heat treatment temperature was determined after thermal characterization by thermogravimetry (TG) and differential scanning calorimetry (DSC). Data was analyzed by ANOVA and Tukey's test at 5% significance level. There was statistical significance for the main factor heat treatment (p=0.03) and composite (p=0.02), for flexural strength. For Knoop hardness, only the main factor composite was statistically significant (p=0.00). P60 presented higher hardness than TPH. No statistically significant correlation between mechanical properties tested was detected. Based on these results, it was possible to conclude that heat treatment influenced flexural strength of direct composites, while it was not observed for hardness. The association of direct composites with a simple post-cure heat treatment may be an alternative for current indirect composite systems, although more studies are needed to verify other properties of the composites for this application.
本研究的目的是验证使用铸造炉进行的实验性热处理（170℃/10分钟）对两种商用直接树脂复合材料（TPH Spectrum和Filtek P60）的机械性能（硬度和弯曲强度）的影响，并与一种商用间接树脂系统（BelleGlass）进行比较。通过热重分析（TG）和差示扫描量热法（DSC）进行热表征后确定热处理温度。数据采用方差分析和Tukey检验，显著性水平为5%。对于弯曲强度，主要因素热处理（p = 0.03）和复合材料（p = 0.02）具有统计学意义。对于努氏硬度，只有主要因素复合材料具有统计学意义（p = 0.00）。P60的硬度高于TPH。在所测试的机械性能之间未检测到统计学上的显著相关性。基于这些结果，可以得出结论，热处理影响直接复合材料的弯曲强度，但未观察到对硬度的影响。直接复合材料与简单的后固化热处理相结合可能是当前间接复合材料系统的一种替代方案，尽管需要更多研究来验证该应用中复合材料的其他性能。
