光固化树脂加强型玻璃离子水门汀即刻剪切强度的测定

目的研究光固化树脂加强型玻璃离子水门汀黏结正畸托槽的即刻剪切强度。方法收集离体前磨牙30颗,随机均分为3组。第1组(对照组):35%磷酸酸蚀30 s,冲洗、干燥,涂黏结剂,京津釉质黏结剂黏结托槽。第2、3组:35%磷酸酸蚀30 s,冲洗,湿润,光固化型的Fuji Ortho Lc树脂加强型玻璃离子黏结托槽。第1、2组24 h后测剪切强度,第3组30 min内测剪切强度。托槽去除后统计牙面上的黏结剂残留量。结果第2组的剪切强度高于第3组,差异有显著性;第1、3组间剪切强度差异无显著性。结论光固化树脂加强型玻璃离子水门汀的即刻黏结强度能够满足临床要求,但24 h后的黏结强度显著增强。

Study of shear bond strength of light-cured and resin-reinforced glass ionomer cement immediately after bonding

Objective To study the shear bond strength of light-cured and resin-reinforced glass ionomer cement immediately after bonding.Methods 30 human premolars were randomly and evenly divided into 3 groups.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.Group 2 and 3:the enamel was etched with 35% phosphoric acid for 30 seconds,rinsed with tap water and left moist,and the brackets were bonded with Fuji Ortho Lc glass ionomer cement.The group 1 and 2 were tested for shear bond strength after 24 hours;the group 3 was tested immediately.Results The shear bond strengths of the three groups were(8.20±2.99)MPa,(10.69±3.17)MPa and(6.99±2.28)MPa,respectively.There was a statistically significant difference between group 2 and 3;there was no statistically significant difference between group 1 and 3.Conclusions The light-cured and resin-reinforced glass ionomer cement can be used in orthodontic treatment immediately after bonding, but the bond strength is significantly lower in immediate bonding than that in 24 hours.