Naiany Macêdo Peixoto; Jefferson David Melo de Matos; Valdir Cabral Andrade; Marco Antonio Bottino & Lucas Villaça Zogheib
Summary
To evaluate the shear strength of cemented orthodontic brackets to a dental ceramic based on lithium disilicate. Rectangular samples 80 based glassceramic lithium disilicate were prepared. The samples were initially divided into 4 groups of 20 discs according to surface treatment: 37 % phosphoric acid for 30 seconds (HP); 10 % hydrofluoric acid for 60 seconds (HF); blasting with aluminum oxide for 4 seconds (SB); and diamond-tipped for 10 seconds (DW). Each group was divided into two subgroups for the Edgwise bracket cementation: metallic and ceramic. The two new groups were subdivided into thermocyclers or nonthermocyclics. The thermocycled samples passed 500 cycles with temperature variations between 5 ° C to 55 ° C. The numerical values obtained in the shear test were submitted to descriptive statistical analysis (mean and standard deviation), and the Shapiro-Wilk normality test and nonparametric Kruskal-Wallis and Mann-Whitney tests were performed. It was found that there was no statistically significant difference in the type of surface treatment and conducting or not thermocycling, observing statistically significant difference only on the bracket type, and the bond strength at higher metal bracket than in ceramics. Thus, the type of surface treatment and thermocycling aging were not decisive in the bond strength of orthodontic brackets to the lithium disilicate ceramic.
KEY WORDS: ceramic, orthodontic brackets, shear strength.
How to cite this article
PEIXOTO, N. M.; DE MATOS, J. D. M.; ANDRADE, V. C.; BOTTINO, M. A. & ZOGHEIB, L. V. Evaluation of union resistance of orthodontic bracelets fixed to lithium dissylate ceramic. Int. J. Odontostomat., 13(2):207-218, 2019.