Influence of brushing on a machined lithium disilicate-based ceramic: assessment of color maintenance and surface roughness / Influência da escovação em uma cerâmica à base de dissilicato de lítio usinada: avaliação da manutenção cromática e rugosidade superficial

ABSTRACT

Objective: To assess the effect of simulated brushing after different treatments in color maintenance and sur-face roughness of a ceramic. Materials and methods: Thirty lithium disilicate ceramic blocks were obtained, sintered, finished with water abrasive paper grit, and divided into Group P- polished with diamond-coated silicone tips; Group G- glaze; Group S- pigment layer and glaze. A brushing simulator machine (37 oC/120 rpm) was used (10,000; 30,000; and 100,000 cycles) and surface roughness analysis was performed before and after this simulation in a rugosimeter (Ra parame-ters - mean roughness). The samples color were assessed with a spectrophotometer (Easyshade, Vita; parameters L*a*b*). Results: Regarding surface roughness, Group P presented statistical difference after 10 years. Group G presented difference for the initial measurement, and after 1 and 3 years. Regarding color, Group P did not vary after 10 years. Group G presented difference for the initial measurement, and after 1 and 3 years; Group P did not vary after brushing, except for 1 and 10 years The initial color of Group G was similar after 1 and 3 ye-ars, however, it presented statistical difference after 10 years. Group S presented similar behavior between the initial periods from 1 to 3 years, however, the initial ?E differed statistically for 10 years. Group S were shown to be statistically different from others for all periods, ex-cept for S and P in 1 year. Conclusion: It was concluded that Group P did not suffer initial color alteration after simulated brushing, and Group G and S suffered color alteration after 10 years of simulated brushing.