العلاقة بين قوة الالصاق المقاومة لقوى القص والشد ونوع المادة اللاصقة المستخدمة في الصاق الحاصرات التقويمية – دراسة مقارنة

Purpose: The purpose of this study was to evaluate the shear and tensile bond strengths of orthodontic brackets bonded with self etching primer and resin-reinforced glass ionomer cement in comparison with light cured resin adhesive. Materials and methods: Sixty extracted human upper premolars were randomly divided into 3 groups. Metal brackets were bonded to the enamel according to 1 of 3 protocols. Group I, teeth were etched with 37% phosphoric acid and brackets bonded with Transbond XT (3M Unitek). Group II, teeth were etched with self-etching primer Transbond Plus(3M Unitek) and brackets bonded with Transbond XT as in Group I. Group III, brackets were bonded with resin-reinforced glass ionomer cement Fuji Ortho LC (G.C. America, Chicago, Ill) without enamel etching in moist condition. Each adhesive group was divided equally into two sub groups . The specimens were stored in distilled water for 24 hours at 4 °C. Brackets were debonded by using a shear and tensile load on Instron testing machine. Shear and tensile bond strength values were recorded. Results: The mean bond strengths (in megapascals) were (8.59, 5.17 respectively) in group I, (10.01, 5.31 respectively) in group II, and (5.08, 3.95 respectively) in group III. ANOVA and Bonferroni test showed a statistically significant difference in mean shear and tensile bond strengths between group II and III whereas the difference between group I and II and between group I and III was not statistically significant. Conclusions: The tested self-etching primer and adhesive systems produced bond strength values higher than that of the light cured resin adhesive whereas the resin-reinforced glass ionomer cement showed a significantly reduced bond strength . Clinically, the use of self-etching primer and adhesive systems is suitable for orthodontic bracket bonding