Polishing Systems in Glass Ionomer Cements: An Experimental Analysis of Surface Roughness and Staining

Abstract

This study compared the roughness and surface staining of two glass ionomer cements (GIC), one conventional and one resin-modified, subjected to two polishing systems, aiming to evaluate the most adequate polishing protocol. Thirty specimens of each material were prepared and divided into three groups: 10 specimens polished with Praxis discs, 10 with the Microdont Mini Kit rubber polishing system, and 10 left unpolished as controls. Surface roughness was evaluated using a profilometer to obtain average roughness values. Colorimetric analysis involved coffee immersion of the specimens, with surface staining variation calculated using a spectrophotometer. The conventional GIC achieved the lowest roughness with the Mini Kit (Ra = 0.474 ± 0.195 μm) and the highest in the control group (Ra = 0.744 ± 0.138 μm). The resin-modified GIC also achieved its lowest roughness with the Mini Kit (Ra = 0.254 ± 0.098 μm), while the highest roughness was associated with the Praxis discs (Ra = 0.988 ± 0.378 μm). Regarding staining, the lowest ΔE values were recorded in the Mini Kit groups for both conventional GIC (ΔE = 3.1 ± 0.8) and resin-modified GIC (ΔE = 1.6 ± 0.3). The highest staining occurred in the Praxis disc groups, for both conventional GIC (ΔE = 4.3 ± 0.6) and resin-modified GIC (ΔE = 2.6 ± 0.3).

Keywords: Glass Ionomer Cements; Dental Polishing; Surface Properties; Surface Roughness; Pigmentation