Impact of simulated toothbrushing on surface properties of chairside CAD-CAM materials: An in vitro study

Chairside computer-aided design and computer-aided manufacturing (CAD-CAM) materials that do not require any firing steps are a promising option to expedite restoration production; however, little information is available to determine the most suitable material for each clinical situation. The purpose of this in vitro study was to evaluate the effect of simulated toothbrushing on surface gloss, roughness, and wear of chairside CAD-CAM materials. Disk-shaped specimens (n=15) were prepared of the following materials: ENA—VITA Enamic; LAV—Lava Ultimate; EMP—IPS Empress CAD; CER—Cerasmart; GRA—Grandio blocs. Gloss (Gloss Unit—GU) and surface roughness (Ra—μm) were evaluated before and after simulated toothbrushing (100 000 strokes). Wear (μm) was assessed by contact profilometry. Additional analyses of microhardness by scanning electron microscopy were also performed. Data were analyzed with 2-way repeated measures ANOVA test for roughness and gloss, and 1-way ANOVA for wear (α=.05). To estimate the correlation between Ra and GU, the Pearson correlation was calculated. Before brushing, CER showed the lowest Ra (PGRA), with the exception of LAVA, which was similar to ENA, and EMP showing improved wear resistance. A strong negative correlation (-0.925) between GU and Ra values was detected (P