Er：YAG激光对根面牙本质与玻璃离子间抗剪切强度的影响

摘要

Objective:To evaluate the effects of Er:YAG laser irradiation on shear strength between glass ionomer cement and root surface dentine in the elderly.Methods:From 20 elderly people(≥ 60)and 20 young people(≤20),their teeth without caries and subfissure were selected from February to May in 2013 for this study and made into specimens with exposed root dentine by cutting the enamel and dentine around the mesial enamel-dentinal junction with a diamond bur.The teeth from the elderly people were randomly di-vided into group G1 and group G2 and those from the young people were randomly divided into group M1 and M2,each group containing 10 teeth.Different techniques were used to prepare the root dentine:Group G1 and group M1 using Er:YAG laser irradiation,group G2 and group M2 using diamond bur preparation.Each tooth was embedded in self-curing plastic,filled with GC Fuji Ⅸ GP CAPSULE glass ionomer cement after preparing the root dentine.All specimens were tested for shear strength in universal testing machine after thermocycling.Results:The comparison of shear strength shows:group G1 >G2,group M1 >M2,group G1 >M1,group G2 >M2 (P<0.05).Conclusions:Er:YAG laser irradiation can improve the shear strength between the dentin and ionomer cement;root dentin of elderly people obtain higher shear bond strength to ionomer cement than those of the young people.%目的：研究铒：钇铝石榴石（Er：YAG）激光照射对老年人根面牙本质与玻璃离子水门汀间的抗剪切强度的影响。方法：收集20颗老年人（≥60岁）和20颗年轻人（≤20岁）完整离体恒牙，用金刚砂车针磨除近中釉牙骨质界部位的牙釉质及牙骨质，暴露根方牙本质。老年人牙齿随机分为 G 1组和 G2组，年轻人牙齿随机分为 M1组和 M2组，每组10颗。采用不同的方式处理根面牙本质：G1组和 M1组用 Er：YAG激光照射，G2组和 M2组仅用金刚砂车针制备。将牙齿包埋于自凝塑料，制备根面使用 GC Fuji Ⅸ GP CAPSULE 玻璃离子充填。样本冷热循环后，置于万能材料试验机测定其抗剪切强度，并行统计学分析。结果：抗剪切强度比较显示：G1组＞G2组，M1组＞M2组，G1组＞M1组，G2组＞M2组（P＜0．05）。结论：Er：YAG激光照射可以提高牙本质与玻璃离子间抗剪切强度；老年人牙齿可以获得比年轻人更高的抗剪切强度。