Effect of cigarette smoke on color stability and surface roughness of dental composites

Objective: To evaluate the color stability and surface roughness of 3 dental composites subjected to cigarette smoke and brushing. Methods: Twenty specimens were prepared for each type of restorative material used: nanohybrid (Tetric N-Ceram); hybrid (Z250-3M ESPE) and silorane-based microhybrid (Filtek P90-3M ESPE), which were divided into 2 groups (n = 10), according to the type of finishing/ polishing received: Group 1 - papers with decreasing abrasive grit and Group 2 - polyester matrix (without polishing). After initial readouts of color (Easy Shade -VITA) and surface roughness (SJ-201P Mitutoyo), specimens were subjected to action of smoke from 20 cigarettes, (Marlboro Red-Philip Morris). After each cigarette, the samples were submitted to brushing in a standardised device. After this, final readouts were taken to calculate change in color (AE and AL) and roughness (ARa), which were statistically analysed (2 -way ANOVA, Bonferroni, and Student's -t tests respectively, p < 0.05). Results: Tetric N-Ceram presented color change at clinically unacceptable levels (AE > 3.3) when the polyester strip was used for finishing, a result differing (p < 0.05) from those of the other composites, which presented no difference between them (p > 0.05). Unpolished composites presented higher Ra values than those that were polished (p < 0.05), with exception of the silorane based composite. Conclusion: Absence of polishing increases cigarette capacity to stain composites and surface roughness of composites, with exception of the silorane based type. CD 2012 Elsevier Ltd. All rights reserved.