目的:采用两种临床常用粘接剂,对个性化机加工底板托槽、新型网底托槽、双向倒钩底板托槽和传统网底托槽的抗剪切强度(shear bond strength,SBS)进行比较研究,为临床个性化机加工托槽的粘接提供参考.方法:收集48颗新鲜人类前磨牙,随机分为8组.A、B组选用个性化机加工底板托槽,C、D组选用新型网底托槽,E、F组选用双向倒钩底板托槽,G、H组选用传统网底托槽;A、C、E、G组使用化学固化粘接剂,B、D、F、H组使用光固化粘接剂.在粘接实验前,在所有托槽中,每种托槽随机选1颗,对其底板在放大40倍、100倍的扫描电镜下进行观察并拍照.使用万能材料实验机,对每组托槽进行SBS的测定,并进行粘接剂残留量(adhesive remnant index,ARI)计分.结果:使用化学固化粘接剂时,其他3种托槽相比,双向倒钩底板托槽粘接强度较低,差异有统计学意义(P＜0.05).使用光固化粘接剂时,双向倒钩底板托槽粘接强度最低,新型网底托槽较低,传统网底托槽和个性化机加工底板托槽粘接强度最高,差异有统计学意义(P＜0.05),传统网底托槽和个性化机加工底板托槽之间粘接强度无明显差异(P＞0.05).各组ARI计分差异有统计学意义(P＜0.05),进一步比较可得:H组ARI计分最小,且H组与A组和E组的差异有统计学意义(P＜0.05).结论:个性化机加工底板托槽使用光固化粘接剂或使用化学固化粘接剂对其粘接强度无明显影响,粘接强度均能满足正畸临床粘接的要求.H组脱粘接断裂部位相对更接近牙釉质,其余各组牙釉质在脱粘接过程中损伤的风险较小.
Shear Bond Strength of Personalized Machined Brackets
Objective:To compare the bonding strength of four types of metal bottom plate brackets.Methods:Forty-eight extracted premolars were randomly assigned to eight main groups,with six teeth in each group.Person-alized machined bottom bracket was adopted in group A and B,new net bottom bracket was adopted in group C and D,two-way barb bottom bracket was adopted in group E and F,and traditional net bottom bracket was adopted in group G and H.Among them,chemically cured resin adhesive was adopted for bonding brackets in group A,C,E,and G,light-cured resin adhesive was adopted for bonding brackets in group B,D,F,and H.Before the bonding experiment,the bottom plate was observed with the scanning electron microscope.The shear strength of each bracket was measured with a universal material testing ma-chine,and the adhesive residue on each bracket was coun-ted.Results:When using chemically cured resin adhesive,the bonding strength of the brackets on the two-way barb bottom bracket was lower than that of other three kinds of brackets(P＜0.05).When using light-cured resin adhesive,compared with other three kinds of brackets,the two-way barb bottom bracket had the lowest bonding strength,the new net bottom bracket had the lowest bonding strength,the traditional net bottom bracket and the personalized ma-chined bottom bracket had the highest bonding strength,and the difference was statistically significant(P＜0.05).There was no significant difference in bonding strength between the traditional net bottom bracket and the personal-ized machined base bracket(P＞0.05).There were significant differences in ARI scores among all groups(P＜0.05).ARI score in group H was the smallest,and the difference between group H,group A,and group E was statistically significant(P＜0.05).Conclusion:The use of chemically cured resin adhesive or light-cured resin adhe-sive has no obvious effect on personalized machined bottom brackets bonding strength,and the bonding strength can meet the requirements of orthodontic clinical bonding.The fracture site of group H was relatively closer to the enamel,and the risk of enamel damage in the other groups was less during the process of debonding.
万方数据
维普
