Impacto do desafio erosivo em resinas para próteses provisórias convencionais e CAD/CAM: uma avaliação das propriedades de superfície.

Abstract

Patients with eating disorders who have dental restorations often experience erosive wear due to the selective leaching of alkaline ions, leading to mechanical, biological, and aesthetic failures. The aim of this study was to evaluate the impact of different surface treatments on materials used for conventional and CAD/CAM provisional fixed prostheses subjected to an erosive challenge. For this purpose, 100 specimens were fabricated and divided among five types of provisional prosthetic resins, each subdivided into two surface treatments: mechanical polishing and Palaseal glaze (n=10). The properties were evaluated at the following time points: initial (T0: baseline) and after aging by erosive challenge with 5% HCl (T1: 23 h; T2: 45 h; T3: 91 h). Surface roughness, color stability, and microhardness analyses were performed. The Shapiro–Wilk test and three-way ANOVA were applied, with a significance level set at p < 0.05. When significant differences were found, the Tukey post hoc test was used for multiple comparisons (p < 0.05). Significant differences were observed for the factors resin, treatment, and time across all analyzed properties (p < 0.001). The polished bisacrylic resin presented the highest values of color change, surface roughness, and microhardness variation. The glaze demonstrated superior effectiveness compared to polishing, improving the properties of all materials (p < 0.001). It was concluded that CAD/CAM resins exhibited better surface stability under erosive challenge compared to conventional resins. The application of glaze is recommended to enhance the longevity of provisional restorations in patients at risk of acid erosion.