两种光固化模式对复合树脂微渗漏的影响

Evaluation of two kinds of light curing modes in microleakage of composite resin

目的比较弱光启动模式和固化光强度不变的常规光模式对复合树脂微渗漏的影响。方法选取40颗离体磨牙,在面备I类洞型,随机分为弱光启动模式组和常规光模式组,每组20颗牙,所有离体牙均进行Z350树脂的光固化充填。样本均用亚甲蓝溶液染色后,颊舌向沿长轴切开,在体式显微镜下观察充填体与牙体洞壁间染料渗透情况。结果弱光启动组的微渗漏程度小于常规光模式组,但差异无统计学意义(P>0.05)。结论弱光启动的光固化模式并不能比固化光强度保持不变的常规固化模式更有效地降低复合树脂(Z350)的微渗漏。

Objective To compare the effect of two kinds of light curing modes on the microleakage.Methods Forty freshly extracted molars were prepared for class Ⅰ cavities on occlusal surface and filled by nanocomposite resin Z350.The teeth were randomly divided into 2 groups of 20.One group was light-cured by soft-start light curing mode,another group was light-cured by traditional high light intensity.The teeth were immersed into 2％ methylene blue dye for 72h under room temperature.All of these teeth were cut along labial-lingual direction and the penetration of dye along the wall of cavities was observed under stereoscopic microscope.Results Soft-start curing mode showed lower microleakage than high light intensity.There was no significant difference between the two groups （P ＞ 0.05）.Conclusion Soft-start light curing mode did not reduce the microleakage of composite resin（Z350）.