Er,Cr:YSGG激光对氟斑牙釉质与铸瓷粘接耐久性的影响

Influence of Er,Cr:YSGG laser irradiation on bonding durability between the enamel of fluorotic teeth and castable ceramic

目的:评价Er,Cr:YSGG激光处理氟斑牙釉质后后者与铸瓷的粘接耐久性,以期为改善氟斑牙釉质与铸瓷贴面的粘接效果提供理论依据。方法:经Dean氏指标筛选无龋坏、无隐裂中度氟斑牙102颗,将其颊面分别制备成不小于3mm×3mm的牙釉质面,将其随机分为3组:涡轮机+磷酸30sec处理组、涡轮机+磷酸60sec处理组、Er,Cr:YSGG激光处理组,每组34个样本。其中每组筛选出24个样本制作成粘接试件,进行即刻微剪切粘接强度测试和冷热循环10000次后微剪切粘接强度测试;每组剩余的10个样本使用表面形貌三维测量仪测量其面粗糙度。结果:无论在即刻组还是温度老化组,Er,Cr:YSGG激光处理组均获得了最高的微剪切粘接强度,但其与涡轮机+磷酸60sec处理组之间差异无统计学意义(P>0.05),该两组的微剪切强度值均显著高于涡轮机+磷酸30sec处理组(P<0.05);在测试各组面粗糙度时,Er,Cr:YSGG激光组获得了最高的表面粗糙度,但其与涡轮机+磷酸60sec处理组之间差异无统计学意义(P>0.05),该两组的面粗糙度显著高于涡轮机+磷酸30sec处理组(P<0.05)。结论:相较于磷酸常规酸蚀而言,Er,Cr:YSGG激光处理氟斑牙釉质后能显著改善后者与铸瓷的粘接强度,在完成进一步激光最佳参数实验研究后可尝试用于临床上氟斑牙瓷贴面的修复病例。

Objective： The purpose of this study was to evaluate the influence of Er,Cr：YSGG laser irradiation on the bonding durability between the enamel of dental fluorosis and IPS e. max Empress Ceramic to provide theoretical basis for improving the bonding effect between the latter two. Methods： According to the Dean＇s index, 102 teeth with moderate fluorosis were prepared and randomly divided into three groups： group A（diamond bur treatment followed by 30 s etching of phosphoric acid）, group B（diamond bur treatment followed by 60 s etching of phosphoric acid） and group C（Er,Cr：YSGG laser irradiation）, the action area in every tooth was no less than 3×3 mm. Firstly, 24 specimens in each group were ramdomly selected to be made into bonding specimens which were suffered from the immediately and after thermocycling10000 times microshear test. Secondly, the surface roughness values of the rest 10 specimens in the three groups were measured by 3 D surface topography measuring instrument. Results： The group C got the highest bonding strength not only in the immediately subgroup but in the thermocycling subgroup, and the bonding strength of the group A was significantly less than the group B and C（P〈0.05）, however, there was no significant difference between the latter two groups（P〉0.05）. In the surface roughness test, the group C got the highest surface roughness value, and the bonding strength of the group A was significantly less than the group B and C（P〈0.05）, however, there was no significant difference between the latter two groups（P〉0.05）. Conclusion： Compared with the conventional etching of phosphoric acid, the Er,Cr：YSGG laser irradiation could obviously improve the bonding effect between the enamel of dental fluorosis and IPS e. max Empress Ceramic,and once getting the optimal working parametres, it could be applied to the clinical cases about the porcelain laminate veneer for dental fluorosis.