Shear bond strength of different accessories used to traction impacted teeth

Abstract

Objectives: To evaluate the shear bond strength and the adhesive remnant index (ARI) of different orthodontic accessories used for applying traction on impacted teeth. Methods: 120 bovine incisors were used. Initially, all teeth were submitted to prophylaxis, subsequent etching with 37% phosphoric acid, application of adhesive and light polymerization. Afterwards, these teeth were randomly divided into eight groups: (1) composite lingual button; (2) hook for application of traction on impacted teeth; (3) hook with chain; (4) cleat; (5) brackets; (6) convex lingual button; (7) concave lingual button; and (8) orthodontic mesh. The groups were submitted to shear tests in a universal test machine, and ARI evaluation. Results: The group of orthodontic mesh (8) presented the best shear bond strength results with statistically significant differences comparing with the composite lingual button (p < 0.001), hooks for application of traction on impacted teeth (p=0.002), hooks with chain (p=0.001), cleat (p=0.011), brackets (p < 0.001), convex lingual button (p=0.003) and convex lingual button (p < 0.001). The highest mean ARI values were also obtained for the mesh group, with statistically significant differences comparing with the composite lingual button (p=0.008), cleat (p=0.004), brackets (p=0.001), convex lingual button (p=0.017) and concave lingual button (p=0.005). Conclusion: The greatest adhesion forces were obtained with the orthodontic mesh, which was statistically different from all other groups, and the lowest adhesion forces with the composite lingual button.