Comparative evaluation of surface roughness and color stability of nanohybrid composite resin after periodic exposure to tea, coffee, and Coca-cola – An in vitro profilometric and image analysis study

AIM: The aim of this study is to evaluate the surface roughness and color stability of a nanohybrid composite resin after exposure to tea, coffee, Coca-cola, and artificial saliva on the 7(th), 14(th), and 28(th) day. MATERIALS AND METHODS: Forty specimens of nanohybrid composite resin discs of dimension 6 mm × 2 mm were fabricated and were randomly divided into four equal groups based on beverages (Group 1: control group – artificial saliva, Group 2: Tea, Group 3: Coffee, and Group 4 : Coca-cola). Baseline readings of surface roughness (Ra) and color change (ΔE) were obtained by profilometer and digital image analysis technique in CIE l*a*b scale followed by the readings (ΔE) taken on the 7(th), 14(th), and 28(th) day of exposure to respective beverages. STATISTICAL ANALYSES: One-way analysis of variance (ANOVA) followed by post hoc Tukey's test and paired t-test along with Pearson's correlation with a P = 0.05. RESULTS: Overall, highest surface roughness was obtained in the samples exposed to Coca-cola followed by coffee and tea while the least surface roughness was obtained in the samples exposed to artificial saliva (control group) which was statistically significant (P < 0.05). Overall highest color change was obtained in tea followed by coffee and Coca-cola. The least color change was observed in the samples exposed to artificial saliva (control group) (P < 0.05). CONCLUSION: Surface roughness and color change were time dependent as both increased with time. Furthermore, greater the surface roughness, more was the color change observed in all the groups at all tested time intervals.