不同功率的Er∶YAG激光对白榴石玻璃陶瓷与树脂粘接面粘接强度的影响

Effects of Er∶YAG laser with different powers on bonding strength of leucite glass ceramic and resin bonding surface

目的:探讨掺铒钇铝石榴石(Er∶YAG)激光处理后白榴石玻璃陶瓷与树脂粘接面剪切粘接强度(SBS)和表面形貌的变化,阐明不同功率Er∶YAG激光作为预处理方式对于瓷修复体粘接面粘接强度的影响,为其临床应用提供参考。方法:将IPS Empress CAD玻璃陶瓷块制备成84个7 mm×6 mm×3 mm的瓷片样本,并根据表面处理方法不同随机分为对照组、酸蚀组、2 W激光组、4 W激光组、6 W激光组、8 W激光组和10 W激光组,每组12个样本。除对照组外对其余各组样本进行表面处理,酸蚀组使用9.5%氢氟酸处理,2 W激光组、4 W激光组、6 W激光组、8 W激光组和10 W激光组分别使用功率为2、4、6、8和10 W的Er∶YAG激光处理。样本表面处理完成后,各组分别选取10个样本采用电子万能试验机检测处理后表面与树脂粘接后的SBS值,然后采用光学立体显微镜观察粘接失效模式。各组剩余2个样本采用扫描电镜(SEM)观察处理后的表面形貌改变。结果:与对照组比较,其他各组样本SBS值均升高(P<0.01);2 W激光组、4 W激光组、6 W激光组、8 W激光组和10 W激光组样本SBS值依次升高,各组间样本SBS值比较差异有统计学意义(P<0.01);与酸蚀组比较,2 W激光组、4 W激光组、6 W激光组和8 W激光组SBS值均降低(P<0.01),10 W激光组样本SBS值差异无统计学意义(P>0.05)。失效模式观察,各组样本失效模式均以粘合剂失效为主,偶见混合失效,无内聚失效。SEM观察,对照组样本表面光滑无变化;酸蚀组样本表面可见许多深浅不一的不规则凹槽,呈现出明显的“蜂窝状”结构;2 W激光组样本表面可见小范围的瓷层剥脱形成的凹坑状改变,4 W激光组样本表面凹坑的面积和深度有所增加,6 W激光组样本表面可见连续的大块剥脱,8 W激光组和10 W激光组样本表面可见凹坑数量增多,呈现出明显的“鳞片状”外观。结论:随着Er∶YAG激光辐照功率的增加,白榴石玻璃陶瓷与树脂之间表现出逐步升高的粘接强度和逐渐粗糙的表面形貌改变,当激光辐照功率达到10W时,能够获得与氢氟酸处理相近的效果。

Objective:To explore the changes of shear bonding strength(SBS)and surface morphology of the bonding surface between leucite glass ceramic and resin after Er∶YAG laser treatment and expound the influence of Er∶YAG laser treatment with different powers as preconditioning method on the bonding strength of the bonding surface of ceramic restoration,and to provide the reference for the clinical application.Methods:The IPS Empress CAD glass ceramic blocks were prepared into 84 ceramic samples with 7 mm×6 mm×3 mm,and randomly divided into control group,acid etching group,2 W laser group,4 W laser group,6 W laser group,8 W laser group and 10 W laser group according to different surface treatment methods(12 samples in each group).Except for control group,surface treatment was carried out on the samples of other groups;the samples in acid etching group were treated with 9.5%hydrofluoric acid,and the samples in 2 W laser group,4 W laser group,6 W laser group,8 W laser group and 10 W laser group were treated with Er∶YAG laser with power of 2,4,6,8 and 10 W,respectively.After the surface treatment of the samples was completed,10 samples from each group were selected and tested by an electronic universal testing machine to detect the SBS values of the treated surface after bonded with the resin,and then the adhesion failure mode was observed by an optical stereoscopic microscope.Scanning electron microscope(SEM)was used to observe the surface morphology of the other two samples in each group.Results:Compared with control group,the SBS values of samples in other groups were all increased(P<0.01).The SBS values of samples in 2 W laser group,4 W laser group,6 W laser group,8 W laser group and 10 W laser group were successively increased,and there were significant differences between various groups(P<0.01).Compared with acid etching group,the SBS values of samples in 2 W laser group,4 W laser group,6 W laser group and 8 W laser group were all decreased(P<0.01),and the SBS value of sample in 10 W laser group had no statistically significant difference(P>0.05).The failure mode observation showed that the failure modes of each group were mainly adhesive failures,occasionally mixed failures,and no cohesive failures.The SEM results showed that the surface of samples in control group was smooth and unchanged;many irregular grooves with different depthes were found in the surface of samples in acid etching group,presenting an obvious honeycomb structure;in 2 W laser group,the pits formed by the peeling of porcelain layer in a small range were observed;in 4 W laser group,the area and depth of pits of samples were increased;in 6 W laser group,continuous bulk peeling was observed;in 8 W laser group and 10 W laser group,the number of pits in surface of the samples was increased,presenting an obvious scale-like appearance.Conclusion:With the increase of the irradiation power of Er∶YAG laser,leucite glass ceramic and resin show a gradually increasing bonding strength and a gradually rough surface morphology change.When the laser power reaches 10 W,the effect is similar to that of hydrofluoric acid treatment.