半导体激光照射对牙齿根尖封闭效果的研究

目的:探讨常规根管预备后使用半导体激光进行根管内照射对根尖封闭性能的影响.方法:选择新鲜拔除的单根管牙60 颗,分6 组(n=10),去除牙冠,常规根管预备.A、B组,半导体激光1 W照射20 s;C、D组,超声荡洗1 min;E、F组,不做任何处理,作为对照组.常规热牙胶垂直加压法充填6 组牙根.微渗漏实验对根充后的A、C、E组牙的根尖封闭性能进行评估,扫描电镜观察B、D、F组牙根剖面.结果:A、C、E组根管微渗漏(mm)分别为1.70±0.82、2.02±0.40和4.56±2.76(A vs E,P<0.01;C vs E,P<0.05,A vs C,P>0.05),扫描电镜观察到激光组大部分牙本质小管发生熔融、缩小或封闭,超声荡洗组大部分牙本质小管内有糊剂或牙胶进入.结论:半导体激光进行根管内照射可以显著提高根充后根尖的封闭性能.

The effect of semiconductor laser irradiation on root cannal seal

Objective:To evaluate the effect of semiconductor lasers irradiation after routine root canal preparation on root cannal seal.Methods:60 Single-rooted freshly extracted human teeth were randomly divided into 6 groups(n=10).The crowns were removed at the cementoenamel junction and the roots were endodontically prepared with conventional methods.The roots in groups A and B were irradiated with 1 W semiconductor laser for 20 s,in group C and D were ultrasonically washed for 1 min,in group E and F without any treatment were used as the controls.Then all the roots were filled by vertical condensation of warm gutta-percha.The root cannal seal was evaluated with microleakage measurement.The data was analyzed by ANOVA.The teeth of group B,D and F were sectioned and examined under scanning electron microscope(SEM).Results:The microleakage(mm) of group A,C and E was 1.70±0.82,2.02±0.40 and 4.56±2.72 respectively(A vs E,P<0.01;C vs E,P<0.05;A vs C,P>0.05).SEM observation showed the melting,narrowness or closure of most dentinal tubules in group B,past and/or gutta-percha in the most dentinal tubules of group D.Conclusion:Semiconductor laser irradiation prior to root cannal filling can promote the effects of cannal seal.