冷热循环对牙本质粘结系统与牙釉质粘结强度的影响

Effect of thermocycling on bond strengths between enamel and dental adhesives

目的评价冷热循环对牙本质粘结系统与牙釉质粘结强度的影响。方法选取人离体下颌第三磨牙20颗,使用600目砂纸打磨颊面釉质,分别使用全酸蚀粘结系统AdperTM Single Bond2(SB2)、两步法自酸蚀粘结系统Clearfil SE Bond(CSE)、一步法自酸蚀粘结系统ClearfilS3Bond(CS3)和iBondGI(IB)进行粘结。实验组冷热循环3000次后测定微拉伸粘结强度,对照组不做冷热循环处理直接测试。结果实验组冷热循环后,各粘结系统粘结强度均有所下降,但与对照组相比,仅IB有显著性差异(P<0.05)。对照组中SB2和CSE的粘结强度相近,明显高于CS3和IB。结论不同牙本质粘结系统与牙釉质的粘结强度存在差异。冷热循环3000次可导致一步法自酸蚀粘结系统IB与牙釉质粘结强度显著性下降。

Objective To evaluate the influence of thermocycling on bond strengths between enamel and dental adhesives. Methods Twenty extracted human third molars were randomly assigned to 4 groups according to the adhesives used,Adper^TM Single Bond 2 （ SB2）, Clearfil SE Bond （ CSE）, Clearfil S3 Bond （ CS3 ） and i Bond GI （IB）. Buccal surfaces were ground with 600 SIC paper. The adhesives were applied according to the manufacturers＇ instructions, and restored with resin composite. After storage in distilled water for 24 h at 37℃, the teeth were sectioned, prepared to the microtensile testing sticks. Half of the specimens from each group were subjected to 3000 thermocycles （5℃ to 55℃）. All the specimens were then subjected to microtensile bond strengths （μTBS） testing. Results Without thermocycling, SB2 and CSE obtained similar strengths which were significantly higher than those of CS3 and IB. After thermocycling, a decrease in bond strengths was observed in all adhesives, but only IB got a more significant decrease than the control. Conclusion The bond strengths were significantly different among adhesives studied, thermocycling for 3000 times could markedly reduce enamel-resin bonding strength of all-in-one adhesive IB.