Effect of charcoal-based dentifrices on surface roughness of an aged resin composite

Recently, the use of whitening dentifrice has increased among patients. However, these products might increase the surface roughness of composite restorations and make them more susceptible to discoloration and plaque accumulation. This study aimed to compare the effects of two charcoal-based dentifrices and other whitening dentifrices with different mechanisms of action on the surface roughness of an aged resin composite.

Forty-five composite specimens were made (2 × 7mm) and their initial surface roughness was obtained using a Profilometer. The specimens were subjected to the Accelerated Artificial Aging (AAA) process for 300 hours. Then, the surface roughness of the specimens was reevaluated using the Profilometer. The specimens were randomly divided into 5 groups (N.=9), namely Control (Gc), Bencer (Gb; Sormeh Company, Tehran, Iran), Perfect White Black (Gp), Colgate Total Whitening (Gt), and Colgate Optic White (Go) (Colgate-Palmolive Company, New York, NY, USA). The specimens were brushed for 14 minutes with respective dentifrices. In the Gc group, the specimens were only brushed with distilled water. The surface roughness of the specimens was measured again. The data were analyzed using repeated measure ANOVA at a significance level of 0.05.

There was no significant difference in surface roughness parameters (Ra, Rq, Rz) between the groups, but in each group, the roughness parameters decreased after the aging procedure and increased after brushing significantly except for Rz parameter in Gb group which increased after aging and decreased after brushing.

None of the whitening dentifrices used in the present study had an adverse effect on the surface roughness of an aged composite resin.