酸蚀对树脂加强型玻璃离子抗剪切强度的影响

Comparative study on the shear bond strength of light-cured glass ionomer cement between etching and nonetching

目的:了解酸蚀和免酸蚀两种情况下光固化树脂加强型玻璃离子水门汀的抗剪切强度是否有差别。方法:收集离体前磨牙30颗,随机平均分为3组。第1组(对照组):35%磷酸酸蚀30s,冲洗、干燥,涂粘结剂,京津釉质粘结剂粘结托槽。第2组:35%磷酸酸蚀30s,冲洗,湿润,光固化型的FujiOrthoLc树脂加强型玻璃离子粘结托槽。第3组:免酸蚀,湿润,光固化型的FujiOrthoLc树脂加强型玻璃离子粘结托槽。24h后用电子万能力学实验机对3组进行抗剪切强度测定,并统计牙面上的粘结剂残留量。结果:2、3组间差异有统计学意义;1、3组间差异无统计学意义。结论:树脂加强型玻璃离子水门汀免酸蚀时其粘结强度能达到临床要求,但是酸蚀后粘结强度明显增高。

Objective To compare the shear bond strength of light-cured glass ionomer cement between etching and nonetching. Methods Thirty human premolars were randomly and evenly divided into 3 groups. In group 1 ,the enamel was etched with 35% phosphoric acid for 30 seconds, rinsed with tap water and dried . Liquid primer was applied and the brackets were bonded with composite resin. In group 2,the enamel was etched with 35% phosphoric acid for 30 seconds, rinsed with tap water and left moist, the brackets were bonded with Fuji Ortho Lc glass ionomer cement. In group 3,the enamel was not conditioned and left moist, the brackets were bonded with Fuji Ortho Lc glass ionomer cement. These three groups were tested for shear bond strength after 24 hours. Results The shear bond strength was 8.20±2.99,10.69±3.17 and 7.38±2.25, respectively. There was statistically significant difference between group 2 and 3（P〈0.05）; There was no significant difference between group 1 and 3（P〈0.05）. Conclusion The light-cured glass ionomer cement can be used in orthodontic treatment when it is not etched, but the shear bond strength is significantly lower than that when it is etched.