Taskeen L Tahoora, Ganesh S Balaji, Jayalakshmi S
Undergraduate Student, Saveetha Dental College and Hospital, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, Tamil Nadu, India.
White Lab. Materials Research Centre, Saveetha Dental College and Hospital, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, Tamil Nadu, India.
J Adv Pharm Technol Res. 2022 Nov;13(Suppl 1):S121-S124. doi: 10.4103/japtr.japtr_252_22. Epub 2022 Nov 30.
Flexural strength is the bend strength or stress which causes failure in bending of the material. Composite is the widely used restorative material in the era of esthetic dentistry as it provides better esthetic and mechanical support for both posterior and anterior teeth. The term "thermocycling" refers to the process of changing temperatures in the mouth. Thus, the aim of the study was to determine the effect of thermocycling on flexural strength in two different composite filling materials. Twelve samples of packable type composite filling material, among which four samples prepared were from Restofill l (Group 1) and four were prepared from Ivoclar Vivadent (Group 2) for the study. Bar-shaped composite resin specimens were prepared with dimensions of 2 mm × 2 mm × 25 mm. Then, the eight samples were subjected to a thermocycling process and four left as control. This was followed by the determination of maximum force by a universal testing machine, and then, the collected data were used to determine flexural strength using the formula. The determining flexural strength was analyzed using SPSS version 23.0 by Independent sample -test. The mean flexural strength of thermocycled Restofill composite filling material is 6.73, whereas the nonthermocycled Restofill sample showed 5.58 and the mean flexural strength of thermocycled Ivoclar Vivadent composite filling material was 5.08. The difference was not statistically significant with = 0.978 >0.05. The current study concludes that the flexural strength of the Restofill composite (Group 1) was higher than the Ivoclar composite (Group 2). Hence, thermocycling affects the flexural strength of composite resin.
挠曲强度是导致材料弯曲失效的弯曲强度或应力。在美学牙科时代，复合材料是广泛使用的修复材料，因为它为前后牙提供了更好的美学和机械支持。术语“热循环”是指口腔内温度变化的过程。因此，本研究的目的是确定热循环对两种不同复合填充材料挠曲强度的影响。制备了12个可压实型复合填充材料样本，其中4个样本由Restofill l制备（第1组），4个由义获嘉伟瓦登特公司制备（第2组）用于该研究。制备了尺寸为2mm×2mm×25mm的条形复合树脂标本。然后，将8个样本进行热循环处理，4个留作对照。随后用万能试验机测定最大力，然后使用公式将收集到的数据用于确定挠曲强度。使用SPSS 23.0版本通过独立样本检验对所测定的挠曲强度进行分析。热循环处理的Restofill复合填充材料的平均挠曲强度为6.73，而未进行热循环处理的Restofill样本显示为5.58，热循环处理的义获嘉伟瓦登特复合填充材料的平均挠曲强度为5.08。差异无统计学意义，P = 0.978>0.05。本研究得出结论，Restofill复合材料（第1组）的挠曲强度高于义获嘉复合材料（第2组）。因此，热循环会影响复合树脂的挠曲强度。
