Davari Abdolrahim, Daneshkazemi Alireza, Behniafar Behnaz, Sheshmani Mahsan
Associate Professor, Department of Operative Dentistry, Member of Social Determinants of Oral Health Research Center, Dental School, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Postgraduate Student of Operative Dentistry, Department of Operative Dentistry, School of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
J Dent (Tehran). 2014 Sep;11(5):569-75. Epub 2014 Sep 30.
Direct composite resin restorations are widely used and the impact of different storage temperatures on composites is not well understood. The purpose of this study was to evaluate the microtensile bond strength of composite to dentin after different pre-curing temperatures.
Occlusal surfaces of 44 human molars were ground with diamond burs under water coolant and polished with 600 grit silicon carbide papers to obtain flat dentin surfaces. The dentin was etched with 37% phosphoric acid and bonded with Adper Single Bond 2 according to the manufacturer's instructions. The specimens were randomly divided into two groups (n=22) according to the composite resin applied: FiltekP60 and Filtek Z250. Each group included three subgroups of composite resin pre-curing temperatures (4°C, 23°C and 37°C). Composite resins were applied to the dentin surfaces in a plastic mold (8mm in diameter and 4mm in length) incrementally and cured. Twenty-two composite-to-dentin hour-glass sticks with one mm(2) cross-sectional area per group were prepared. Microtensile bond strength measurements were made using a universal testing machine at a crosshead speed of one mm/min. For statistical analysis, t-test, one-way and two-way ANOVA were used. The level of significance was set at P<0.05.
Filtek P60 pre-heated at 37ºC had significantly higher microtensile bond strength than Filtek Z250 under the same condition. The microtensile bond strengths were not significantly different at 4ºC, 23ºC and 37ºC subgroups of each composite resin group.
Filtek P60 and Filtek Z250 did not have significantly different microtensile bond strengths at 4ºC and 23ºC but Filtek P60 had significantly higher microtensile bond strength at 37 ºC. Composite and temperature interactions had significant effects on the bond strength.
直接复合树脂修复应用广泛，但不同储存温度对复合材料的影响尚不明确。本研究旨在评估不同预固化温度后复合材料与牙本质的微拉伸粘结强度。
44颗人磨牙的咬合面在水冷条件下用金刚石车针打磨，并用600目碳化硅砂纸抛光以获得平整的牙本质表面。用37%磷酸蚀刻牙本质，并按照制造商说明用Adper Single Bond 2粘结。根据应用的复合树脂将标本随机分为两组（n = 22）：Filtek P60和Filtek Z250。每组包括复合树脂预固化温度的三个亚组（4°C、23°C和37°C）。将复合树脂增量施加到塑料模具（直径8mm，长度4mm）中的牙本质表面并固化。每组制备22根横截面面积为1mm²的复合树脂 - 牙本质沙漏形棒。使用万能试验机以1mm/min的十字头速度进行微拉伸粘结强度测量。进行统计分析时，使用t检验、单向和双向方差分析。显著性水平设定为P<0.05。
在相同条件下，37ºC预热的Filtek P60的微拉伸粘结强度显著高于Filtek Z250。每种复合树脂组在4ºC、23ºC和37ºC亚组中的微拉伸粘结强度无显著差异。
Filtek P60和Filtek Z250在4ºC和23ºC时微拉伸粘结强度无显著差异，但在37ºC时Filtek P60的微拉伸粘结强度显著更高。复合材料和温度相互作用对粘结强度有显著影响。
