不同处理方式对通用粘接剂光固化后唾液污染的乳牙牙本质粘接强度的影响

Effect of different decontaminations on bond strength of salivary contaminated dentin of primary teeth after light curing of the universal adhesive

目的探究不同处理方式对通用粘接剂光固化后唾液污染的乳牙牙本质粘接强度的影响。方法选取人60颗无龋坏乳磨牙,磨除牙合面牙釉质至牙本质。随机分成6组:对照组(A组),其余5组粘接剂光固化后唾液污染分别进行吹干(B组)、水冲洗后吹干(C组)、直接涂粘接剂并光固化(D组)、吹干后涂一层粘接剂并光固化(E组)、水冲洗后吹干涂一层粘接剂并光固化(F组),用复合树脂(Filtek Z250)分层充填并光固化。37℃水浴24 h后测试其微拉伸强度及扫描电镜观察。结果 E组微拉伸强度最高,D组最弱;B组、C组、D组断裂多在混合层底部,树脂突不明显;A组、E组、F组断裂多在混合层中部,树脂突较明显。结论通用粘接剂光固化后受到唾液污染,牙本质表面清洁后重涂粘接剂是恢复粘接强度必要的手段。

Objective To investigate the effects of different decontaminations on bond strength of salivary contaminated dentin of primary teeth after light curing of the universal adhesive.Methods Extracted human primary molars(60)were ground to mid-coronal dentin.The dentin specimens were randomly divided into 6 groups(n=10/group)for a one-step universal adhesive(Single Bond Universal Adhesive):no saliva contamination(group A);saliva contamination after light curing of the adhesive followed by air drying(group B),rinsing with water spray/air drying(group C),direct reapplication of the adhesive and light curing(group D),air drying/reapplication of the adhesive and light curing(group E)or rinsing with water spray/air drying/reapplication of the adhesive and light curing(group F).Resin composite(Filtek Z250)was applied on the treated dentin surfaces.The specimens were stored at 37°C and 100%humidity for 24 h.After storage,micro-tensile strength was measured and scanning electron microscope observation(SEM)was conducted.Results The micro-tensile strength of the group E was the highest,while that of the group D was the weakest.The fracture of the group of B,C and D was mostly at the bottom of mixed layer,and resin was not obvious.The fracture of the group of A,E and F was mostly in the middle of mixed layer,and resin was obvious.Conclusion When saliva contamination happens after light curing of the universal adhesive,the reapplication of the adhesive after cleaning the dentin surface is necessary for restoring the bond strength.