Surface characterization of current composites after toothbrush abrasion

Abstract

The present study was designed to evaluate the surface roughness and the gloss of current composites before and after toothbrush abrasion. We assessed forty dimensionally standardized composite specimens (n=8/group) from five composites: two nanohybrids (i.e., IPS Empress Direct Enamel and IPS Empress Direct Dentin), two microhybrids (i.e., Clearfil AP-X and Filtek Z250) and one organically modified ceramics (Admira). All of the specimens were polished with 4000-grid silicon carbide papers. Surface roughness was measured with a profilometer and gloss was measured with a glossmeter before and after powered toothbrush abrasion with a 1:1 slurry (dentifrice/tap water) at 12,000 strokes in a toothbrush simulator. There was a significant increase in the surface roughness and a reduction in gloss after toothbrush abrasion in all of the composites except Clearfil AP-X (p<0.05). Simple regression analysis showed that there was not an association between the surface roughness and the gloss (R 2 =0.191, p<0.001).

Surface roughness and gloss of current CAD/CAM resin composites before and after toothbrush abrasion

“…Although a significant difference in the mean gloss units between the ceramic block and five composite materials was detected before toothbrush abrasion, the gloss unit values of the composite materials were greater than 82.6 GU. Takahashi et al reported that the human eye cannot distinguish between high and very high luster of over 70 GU 15) . After toothbrush abrasion, the gloss unit values of all materials were greater than 70 GU, with the exception of the Shofu Block HC material.…”

“…The surface gloss of the specimens before and after the toothbrush abrasion test was expressed in gloss units (GU) and was measured using a gloss meter (GM-26D, Murakami Color Research Laboratory, Tokyo, Japan) with an incident angle of 60º 15) . The gloss meter was calibrated with a reference black board of a known gloss value.…”

Microleakage and penetration depth of different fissure sealant materials after cyclic thermo-mechanic and brushing simulation

“…By mixing a 2:1 ratio by volume of deionized water and a daily used dentifrice (Colgate Total, Colgate-Palmolive, England), the slurry, which was used as a third medium in the brushing simulation, was prepared. For one year, 10,000 strokes were performed at a frequency of 1 Hz; a double pass of the toothbrush head on the specimen was considered a stroke 14,15) . The toothbrushes were changed after every 10,000 strokes.…”

Toothbrushing alters the surface roughness and gloss of composite resin CAD/CAM blocks

“…Gloss characterizes the specular reflection of the restoration surface 21) . Regression analysis has been used to predict the relationship between Ra and gloss of the examined surface 22) . However, a consensus of their relationship has not been established.…”