Evaluation of roughness, hardness, and surface of ionomer glass cements after submission to different systems of finishing and polishing

Abstract Introduction The roughness of glass ionomer cement (GIC) is a limitation that interferes with its mechanical and aesthetic performance, and it is necessary to use appropriate finishing and polishing procedures in restorations produced with this material. Objective To evaluate the effect of different finishing and polishing systems on roughness, hardness and surface of restorations performed with two types of GIC. Material and method 100 specimens were made and divided into 10 groups, according to the type of GIC (conventional and resin modified GIC) and the finishing and polishing system used (C (Control) - Mylar strip; PD - diamond burs; DA - abrasive disks; PE - Enhance system; BM - carbide burs). After 7 days in distilled water, the specimens were evaluated by Scanning Electron Microscopy (SEM) and submitted to surface roughness and Vickers microhardness tests. Statistical analysis was performed by two-way ANOVA and Tukey post-test. Result SEM analysis demonstrated a smoother surface in BM group in both types of GIC. Regarding roughness, a statistically significant difference (p <0.05) was observed between some groups of conventional GIC, but there was no difference between GIC types. Regarding hardness, conventional GIC showed better results than resin-modified GIC; Concerning to finishing and polishing materials factor, there was no statistically significant difference, regardless of the type of GIC. Conclusion BM groups presented better results on SEM; The type of GIC did not influence the roughness values; The type of polishing did not influence the hardness.