Avaliação da influência do tratamento térmico do silano sobre a resistência de união entre cimentos resinosos e uma cerâmica feldspática

Abstract

The aim of this study was to evaluate three hypotheses: H0- Heat treatment of silane and resin cement type does not influence the bond strength of resin cements and a feldspathic ceramic;H1- Heat treatment of silane influences the bond strength between cements resin and a feldspathic ceramic; H2- The resin cement influences the bond strength of a feldspathic ceramic. Thirty blocks were fabricated using a ceramic (VITA Mark II, Zahnfabrik), which were duplicated in composite resin (W3D Master, Wilcos). The blocks were divided into 6 groups (n = 5) in accordance with the following surface treatments: ASCp- Hydrofluoric acid 10% + silane + Panavia F; ASTCp- Hydrofluoric acid 10% + silane + heat treatment (furnace) + Panavia F; STCp- Silane + heat treatment (furnace) + Panavia F; ASCr- Hydrofluoric acid 10% + silane + RelyX ARC; ASTCr- Hydrofluoric acid 10% + silane + heat treatment (furnace) + RelyX ARC; STCr- Silane + heat treatment (furnace) + RelyX ARC. To perform the heat treatment silane was used furnace under temperature of 100 ° C for 2 minutes. Then each ceramic block conditioning was already attached to its corresponding composite resin, using a resin cement to its respective group, under the constant load of 750g. Each set ceramic / cement / composite resin was sectioned and the specimens were analyzed by microtensile mechanical test. The bond strength values and standard deviations (MPa) for the groups were: ASCp (25.47 ± 9.34a); ASTCp (33.04 ± 10.65b); STCp (13.76 ± 8.82c); ASCr (24.80 ± 7.99a); ASTCr (23.84 ± 7.16a); STCr (11.41 ± 11.71c). ANOVA and Post Hoc were applied. With the results of this study, we can conclude: The hypothesis H0 was rejected; H1 hypothesis was partially accepted because the heat treatment of the silane led to the highest average bond strength provided it is conducted in association with the hydrofluoric acid etching 10%, independent of the resin cement tested; H2 hypothesis was partially accepted because the cement with MDP averaged bond strength statistically superior to conventional cement when the conditioning was conducted with 10% hydrofluoric acid prior to the heat treatment of silane.