Does shear bond strength improve with the elastic with impact buffer associated with the orthodontic bracket?

Vol. 16 – Number 64 – 2023 Original article Page 101-105 Does shear bond strength improve with the elastic with impact buffer associated with the orthodontic bracket? Fabiana Correa Mostafa Maia de Carvalho¹ Diego Patrik Alves Carneiro¹ Patrícia Rafaela dos Santos¹ Mário Vedovello Filho¹ Sílvia Amélia Scudeler Vedovello¹ Heloísa Cristina Valdrigh¹ Abstract This in vitro study aimed to evaluate the shear bond strength (RUC) of the orthodontic bracket associated with the Guard elastic as an impact absorber and the remaining adhesive index (ARI). Sixty human premolars were selected and randomly distributed in three groups (n = 20): G1) without elastic; G2) with conventional elastic (3M Unitek); and G3) with Guard elastic (3M Unitek). Kirium Roth slot brackets 0.22 inch (3M ESPE) was fixed to the middle third of the buccal face of the tooth with Transbond XT resin (3M Unitek) and photoactivated for 3 seconds on each bracket face with the Valo (Ultradent) device. After storage for 24 hours, the samples were subjected to a speed of 1 mm/minute. The brackets were taken off, and the ARI was evaluated in a tereomicroscope (Olympus) in 8x magnification. The RUC data were subjected to analysis of variance and Tukey’s test (α = 0.05), and ARI data were subjected to Fisher’s exact test. G3 showed RUC values (20.1 ± 4.5) significantly higher than the group without elastic G1 (15.3 ± 3.7) (P < 0.05). No statistical difference was observed between G2 (16.9 ± 6.0) and the other groups (P > 0.05). There was no significant difference between groups in the assessment of ARI (P = 0.3303). In conclusion, completing the RUC of the Guard and the conventional elastic band was superior concerning the other groups. Less than half of the resin remained in the tooth in all groups studied for the ARI. Descriptors: Shear strength, orthodontic brackets, Orthodontics. ¹ Department of Orthodontics – Faculty of Dentistry of Araras – University Center of the Hermínio Ometto Foundation. DOI: 10.24077/2023;1662-01984123