Saturday, July 27, 2013

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

Volume 41, Supplement 3, August 2013, Pages e73–e79
Journal of Color and Apperance in Dentistry

Abstract

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 (ΔE and ΔL) and roughness (ΔRa), 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 (ΔE > 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.


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