Effect of Toothbrushing on Surface Roughness and Shade of Extrinsically Stained Pressable Ceramic Restorations

The purpose of this study was to investigate the effects of toothbrushing on surface roughness and shade change of extrinsically stained pressable ceramic restorations. Materials and Methods: Two materials, IPS Empress Esthetic and IPS e.max Press, were studied. For each material, 24 disc-shaped specimens, 10mm (diameter) x 3mm (height) were fabricated. Three different methods (n=8) of applying extrinsic stain was performed on each material: Glazed (G): glazed only (control); Stain then Glaze (SG): stained and fired, then glazed and fired. Stained and Glazed (T): glazed and stained together. Samples where brushed using a multi-station brushing machine. Each specimen was brushed for 72, 144, 216 and 288 h (equivalent to 3, 6, 9 and 12 years of simulated toothbrushing twice a day for 2 min) with a force of 200 g at a rate of 90 strokes/min using a soft, straight Oral-B #35 toothbrush and a 1:1 toothpaste and distilled water slurry. Roughness and color were evaluated at baseline and every 3 year equivalent up to 12 years of simulated toothbrushing. Results: No significant difference was found for surface roughness or shade change over time irrespective of technique for the IPS Empress Esthetic (EE) groups. IPS e.max Press (EP) demonstrated an increase roughness over time (P\u3c.01) irrespective of technique (P=.709). Shade change over time depended on the technique (P=.005). The stain then glaze (EP-SG) behaved better over time (P=.039). Conclusions: Within the limitations of this study it can be concluded that no clinically significant shade change for both IPS Empress Esthetic and IPS e.max Press should be expected after 12 years of toothbrushing. IPS Empress Esthetic stains and glaze were more resistant to toothbrush abrasion

Effect of Toothbrushing On Shade and Surface Roughness of Extrinsically Stained Pressable Ceramics

Statement of problem The effect of toothbrushing on extrinsically stained pressable ceramic materials is unknown. Purpose The purpose of this in vitro study was to investigate the effects of toothbrushing on the shade and surface roughness of extrinsically stained, pressable ceramics. Material and Methods Two materials, leucite-based (IPS Empress Esthetic [EE]; Ivoclar Vivadent AG) and lithium disilicate-based ceramic (IPS e.max Press [EP]; Ivoclar Vivadent AG), were studied. For each material, 24 disk-shaped specimens, 10 mm (diameter)×3 mm (height) were fabricated. Three different methods (n=8) of applying extrinsic stains were performed on each material: glazed only (G, control group); stained then glazed (SG); and stained and glazed together (T). The specimens were brushed with a multistation brushing machine under a load of 1.96 N at a rate of 90 strokes per minute with a soft and straight toothbrush (Oral-B #35) and a 1:1 toothpaste and distilled water slurry. Shade and roughness were measured at baseline and at 72, 144, 216, and 288 hours, which is equivalent to 3, 6, 9, and 12 years of simulated toothbrushing for 2 minutes twice a day. A repeated measures ANOVA with staining technique as a fixed factor was used to evaluate shade and roughness (α=.05). Results For EE groups, no significant change was found after 12 years of simulated toothbrushing regarding shade and surface roughness, irrespective of staining techniques (P\u3e.05). However, EP groups demonstrated a significant shade change and an increase in surface roughness after 12 years of simulated toothbrushing. Shade change was found to depend on the method of applying stain. For the EP-SG technique, a significant shade change was observed only at the 9- to 12-year interval (P=.047). However, the EP-T technique demonstrated a significant difference in shade between baseline and 3 years (P=.005) and in the 6- to 9-year interval (P=.005). Surface roughness was only significantly affected at baseline and 3 years for the EP-T group (P=.005). Conclusions For the shade and surface roughness of the EE groups, no statistically significant difference was found after 12 years of toothbrushing, irrespective of the staining technique. The shade and surface roughness of the EP groups were significantly statistically affected by toothbrushing time; only shade changes were found to depend on technique