树脂加强型玻璃离子水门汀在托槽粘结中的应用

目的探讨两种树脂加强型玻璃离子水门汀对托槽粘结强度的影响。方法收集离体人前磨牙60个,随机分成6组。第1组和第2组(对照组):35%磷酸酸蚀30 s,冲洗、吹干,涂粘结剂,采用光固化复合树脂粘结托槽。第3、4、5、6组:10%聚丙烯酸酸蚀30 s,冲洗,保持潮湿,第3组和第4组采用化学固化型的Fuji Ortho树脂加强型玻璃离子水门汀粘结托槽,第5组和第6组采用光固化型的Fuji Ortho LC树脂加强型玻璃离子水门汀粘结托槽。第1、3、5组进行抗剪强度测定,第24、、6组进行抗张强度测定,测试后观察断面形态。结果光固化复合树脂的抗剪强度高于其他2组,抗张强度各组间差异无显著性。各种材料的抗剪强度均高于抗张强度。在断面形态观察中,第1组与第3组、第5组差异有显著性,其余差异无显著性。结论两种树脂加强型玻璃离子水门汀的抗剪强度低于复合树脂,但能满足临床的需要。

Effects of resin-reinforced glass ionomer cement on orthodontic bracket bonding

Objective To study the tensile and shear bond strength of resin-reinforced glass ionomer cement(RGIC) on orthodontic brackets.Methods 60 human premolars were selected and divided into six groups by random.Group 1 and group 2(control): The enamel was etched with 35% phosphoric acid for 30 seconds,rinsed with deironized water and dried.Liquid primer of the Transbond XT was applied and the brackets were bonded with the light-curing composite resin.Group 3 and group 4: conditioned with 10% polyacrylic acid for 30 seconds,rinsed with deironized water and left moist.Power and liquid of Fuji Ortho were measured with an electronic balance and mixed,applying for brackets bonding.Group 5 and group 6: conditioned with 10% polyacrylic acid for 30 seconds,rinsed with deironized water and left moist.The adhesive-filled Fuji Ortho LC(FOLC,GC Corporation) capsule was activated by manual squeezing and then triturated for 10 seconds at approximately 4 000 r/min,applying for brackets bonding.The group 1,3,5 were tested for shear bond strength and the group 2,4,6 for tensile bond strength.The enamel surfaces were examined after debonding.Results Except that the shear bond strength of group 1 was higher than these of group 3 and group 5,there was no significant difference between all the other groups.The shear bond strength was higher than the tensile bond strength for three materials.There was most adhesive remnant on the enamel tested in group 1 in the three odd groups and no significant difference between the three even groups.Conclusion The two RGIC can be used in orthodontics,though the shear bond strengths of them are significantly lower than those of composite resin.