陈旧性树脂表面形态对新旧树脂间粘结强度的影响

目的：研究陈旧性树脂表面形态学改变以及对新旧树脂间粘结强度的影响。方法：制备Z350纳米树脂样本10例,浸泡于37℃蒸馏水中1个月后,使用同种树脂完成样本制备,用体视显微镜和扫描电镜对样本的表面及切面进行形态学观察。万能材料试验机上测定材料的微拉伸强度。结果：陈旧性树脂表面纳米填料颗粒从树脂基质中消失,且新旧树脂间存在间隙,陈旧性树脂修复后微拉伸强度明显降低。结论：新旧树脂界面是导致树脂粘结强度下降的薄弱区。

Study on the surface morphology and bond strength of aged composite resin

Objective：To determine the change of morphology and micro-tensile strength between fresh and aged composite resin.Methods：After being stored in distilled water at 37 ℃ for a month,ten specimens were used as substrate for the new Z350 composite to adhere to.Specimens were then tested for the micro-tensile bond strength （ μTBS） in a universal testing machine at a crosshead speed of 1 mm/min until failure.The surface and incisal surface morphology was analyzed using stereoscopic microscope and scanning electron microscope.Results：μTBS of aged composite resin was significantly lower than that of the fresh resin composite.The nano particles vanished from the resin matrix on the surface of aged composite resin.A rough resin-resin interface appeared between fresh and aged composite resin.Conclusions：The surface of aged composite resin may affect the bond strength between fresh and aged composite resin.