Evaluation of the influence of different bracket bases designs on debonding force and resin remnant

Vol. 16 – Number 61 – 2023 Na Visão D’elas Page 72-79 Evaluation of the influence of different bracket bases designs on debonding force and resin remnant Liliana Ávila Maltagliati1 Hélder Luiz Batista Brum2 Camila Ferreira Rocha2 Hélio Doyle Pereira da Silva3 Mayara Paim Patel4 Abstract The contemporary production of orthodontic brackets includes injection technology, with different designs of bonding bases that interfere directly with the bond strength to enamel and the ease of subsequent removal. The aim was to evaluate the shear bond strength of metal brackets of three different bonding bases, checking the force required for debonding and the rates of resin remaining on the bracket base. The sample consisted of 30 bovine teeth bonded with brackets U-Clip (Orthometric, Marília, SP, Brazil), ID-ALL (ID-Logical, São José do Rio Preto, SP, Brazil), and Mini Twin (3M ESPE, St Paul, Minnesota, USA). All brackets were bonded with Transbond XT resin (3M ESPE, St Paul, Minnesota, USA). After bonding, the specimens were subjected to a shear bond test. The forces required for debonding were recorded. Posteriorly, the remaining adhesive and failure patterns were evaluated in an optical stereomicroscope. The shear forces were similar for U-Clip and ID-ALL, which were significantly different from the Mini-Twin group. The U-Clip and Mini-Twin brackets showed the resin remnant totally adhered to the bracket base, while the ID-ALL bracket had more than half of the resin remnant attached to the bracket base, a statistically significant result. It was concluded that shear forces were lower for the national brackets, statistically significant. Bracket ID-ALL had the least resin remnant in the base, denoting that the fracture occurred in the resin layer. In contrast, in the U-Clip and Mini-Twin brackets groups, the fracture occurred at the resin/enamel interface. Descriptors: shear bond strength, dental enamel, orthodontic bracket, orthodontics. 1 Ph.D. in Orthodontics, Undergraduate and Graduate Professor – Guarulhos University. 2 Undergraduate student in Dentistry, Scientific initiation student – ​​Guarulho University 3 Ph.D. in Statistics, Undergraduate and Graduate Professor – Guarulhos University. 4 Ph.D. in Orthodontics, Undergraduate and Graduate Professor – Guarulhos University. DOI: 10.24077/2023;1661-d889634157