不同参数激光处理根管对纤维桩粘结强度影响的实验研究

Efficacy of Er:YAG Laser Treatments of Root Canal Walls on the Pull-out Bond Strength of Fiber Posts

目的:研究不同参数Er:YAG激光处理根管壁牙本质对纤维桩粘结强度的影响,为激光临床应用提供参考。方法:收集60颗人类上颌中切牙,根据不同处理方法随机分为5组;空白对照组;3 W-50μs Er:YAG激光组;3 W-100μs Er:YAG激光组;4.5 W-50μs Er:YAG激光组;4.5 W-100μs Er:YAG激光组,每组12颗。离体牙根管预备,充填,桩道预备后,Bisco树脂加强型纤维桩通过RelyXTM Unicem粘结树脂水门汀粘固于根管内。流水状态下慢速锯将纤维桩外周平行片切,再垂直粘结面片于试件1mm、4mm、7mm处切成三段1.0mm×1.0mm的长方形柱状试件,进行微拉伸强度测试。不同根管处理方法与牙根不同区域微拉伸强度均数采用两因素方差分析(α=0.05)。电镜下进行断裂类型分析,组件不同类型断裂率采用χ2检验(α=0.05)。结果:3 W10-100μs Er:YAG组拉伸强度值最高(5.55±0.97)MPa,与对照组(4.06±1.22)MPa相比较差异有显著性(P<0.05)。根管上部和中部粘结强度高于根管下部,差异有显著性(P<0.05)。结论:Er:YAG激光处理牙本质表面对其与纤维桩粘结强度的影响与激光功率大小和脉冲持续时间有关,3 W-100μs Er:YAG激光处理表面可以显著增强纤维桩与根管牙本质的粘结强度。

Objective：To evaluate the effects of Er：YAG laser irradiation under different power settings on the micro tensile bond strength（μTBS）of fiber-reinforced composite posts.Methods：Root canals of 60single-rooted human teeth were filled and post spaces were prepared.Specimens were divided randomly into five groups,each consisting of 12 specimens as follows：control group,3W-50μs Er：YAG laser,3W-100μs Er：YAG laser,4.5W-50μs Er：YAG laser,and 4.5W-100μs Er：YAG laser.After the root canal procedures,fiber posts were cemented to the root canal.Micro-tensile bond strength tests were performed using a universal testing machine at a crosshead speed of 1mm/min.The data were analyzed using a two-way ANOVA test（α=0.05）.Results：Irradiation by the 3W-100μs Er：YAG laser positively affected the micro-tensile bond strength（5.55±0.97MPa）.The bond strength was significantly higher than that of control group（4.06±1.22 MPa,P〈0.05）.Conclusion：Er：YAG laser may alter the dentin bond durability.