不同表面处理对聚乳酸可吸收桩与树脂核间粘结性能的影响

摘要

目的：探讨不同表面处理方法对聚乳酸桩与树脂核粘结性能的影响。方法：将25根聚乳酸桩随机分为 A、B、C、D、E 5组（n ＝5），A 组表面仅涂布粘结剂；B 组表面涂布氯仿后再涂布粘结剂；C 组表面涂布氯仿与粘结剂按1∶1混合5 s 后的混合物；D 组表面涂布氯仿与粘结剂按1∶2混合5 s 的混合物；E 组表面涂布氯仿与粘结剂按2∶1混合5 s 的混合物；另取 5根玻璃纤维桩作为 F 组（对照组），表面涂布粘结剂。处理后的各组桩分别与 Filtek Z350树脂核粘结制成棒状试件后进行微拉伸测试；体视显微镜观察各样本的断裂类型， SEM观察桩－树脂核断裂界面；并对数据进行统计分析。结果：C 组微拉伸强度最高（20．58±3．35）MPa，与其他各组相比 P ＜0．05；随后依次为 E 组（13．35±3．21）MPa、D 组（12．80±2．77）MPa、F 组（12．24±1．40）MPa、B组（10．91±1．61）MPa、A 组（5．03±1．48）MPa，两两相比，B 组与 E 组比较，P ＜0．05，D、E、F 组间比较P ＞0．05，其余各组间差异 P ＜0．05；各组断裂模式两两相比 P ＜0．05，C 组以树脂内聚破坏为主。结论：将氯仿和粘结剂按1∶1的比例混合后处理聚乳酸桩表面可提高聚乳酸桩－树脂核的粘结强度。%AIM:To evaluate the effect of different surface treatment on the microtensile bond strength be-tween PLA post and composite resin core.METHODS:25 PLA posts were randomly divided into 5 groups(n =5)and coated with total-etch adhesive Prime&Bond NT (PB)(Group A),chloroform and then coated with PB(Group B);the mixture of chloroform and PB(C-PB)with the proportion of 1 ∶1(C-PB 1 ∶1)(Group C);the mixture of C-PB 1 ∶2(Group D);the mixture of C-PB 2 ∶1(Group E),respectively.5 quartz fiber posts coated with PB were set as group F.All treated posts were cemented with composite resin cores and shaped as rod-like bonding specimens and subjected to the microtensile bonding strength test.Failure modes of the specimens were observed under a stereo-microscope.Surface morphologies of fractured specimens were assessed by SEM.Data were statistically analyzed. RESULTS:The highest microtensile bond strength(MPa)was showed in group C (20.58 ±3.35,vs other groups P <0.05),followed by group E (13.35 ±3.21),D (12.80 ±2.77),F (12.24 ±1.40),B (10.91 ±1.61)and A (5.03 ±1.48).There was difference between each 2 of all the groups in fracture mode (P =0.000).In group C,the most common type of failure was resin cohe-sive failure.CONCLUSION:The microtensile bond strength between PLA post and composite resin core might be affected by the surface treatments of PLA post.The mixture of chloroform and PB with the proportion of 1 ∶1 may improve the adhesive strength between composite resin core and PLA posts.