Er：YAG激光照射对牙釉质与玻璃离子粘接的影响

Effect of Er: YAG laser irradiation on bond strength of glass-ionomer cement to enamel

目的:采用剪切力测试,比较Er:YAG激光照射对牙釉质与玻璃离子之间剪切粘接强度的影响.方法:选取105颗年轻前磨牙、第三磨牙,用涡轮手机按近远中方向将离体牙切割成颊/舌两部分.将受试牙随机分成7组,1组:裂钻预备,2组:裂钻+37%磷酸,3组:裂钻+玻璃离子液,4组:Er:YAG激光预备,5组:Er:YAG激光+37%磷酸,6组:37%磷酸+玻璃离子液,7组:Er:YAG激光+二次激光.玻璃离子充填,将粘接试件置于37°蒸馏水中储存24小时后进行剪切力测试,计算粘接试件牙的抗剪切粘接强度.扫描电子显微镜观察牙釉质经不同处理后的表面形态变化。结果:37%磷酸和玻璃离子液预处理均有助于即刻剪切粘接强度的提高,差异有统计学意义(p<0.05)。激光预备较裂钻预备的即刻剪切粘接强度大,差异有统计学意义(p<0.05)。而在激光预备面的基础上使用37%磷酸预处理和二次激光的应用与单纯的激光预备相比,其即刻剪切粘接强度并未提高,差异无统计学意义(p>0.05)。结论:Er:YAG激光预备、37%磷酸和玻璃离子液都可以提高牙釉质和玻璃离子之间的剪切粘接强度.37%磷酸、玻璃离子液预处理及二次激光不能使Er:YAG激光预备后的剪切粘接强度提高。

Objective： To investigate the effect of glass ionomer cement （GIC） bonding to enamel surfaces after the Er： YAG laser preparing by shear bond strength （SBS） test. Methods： One hundred and five human young premolars and molars teeth were bisected longitudinally in a mesio-distal direction with a diamond saw. The specimens were randomly divided into seven groups , 1： bur preparation, 2： bur preparation ＋ acid by 37% phosphoric acid, 3： bur preparation ~ GIC liquid, 4： laser preparation, 5： la- ser preparation ＋ acid by 37% phosphoric acid, 6： laser preparation ＋ GIC liquid; 7： laser preparation ＋ second laser. We then filled GIC, test after storing 24 hours in distilled water, evaluated for shear bond strength and observed under a scanning electron （SEM）. Results： Pretreatment with37% phosphoric acid and GIC liquid could improve SBS of GIC bonded to bur-prepared enam- el. Laser preparation resulted in more SBS than in bur preparation. A significant difference was observed. However, 37% phos- phoric acid and second laser followed laser preparation did not improve SBS. There was no significant difference between these groups. Conclusions： Er： YAG laser preparation, 37% phosphoric acid or GIC liquid could improve SBS of GIC bonded to bur-prepared enamel. However, the 37% phosphoric acid, GIC liquid or the second laser for Er： YAG laser-prepared enamel could not make the SBS increased.