The Effect of Carbonated Beverage on the Surface Morphology of Bleached Enamel- an In Vitro Study

Aim: The purpose of this study was to evaluate the effect of carbonated beverage, Coca-Cola on 15%
carbamide peroxide gel bleached enamel under Scanning Electron Microscope (SEM).
Materials and Methods: 40 premolars were embedded into acrylic blocks with their buccal enamel surface
exposed. They were divided into 5 groups (A,B,C,D and E) and each group having 8 number of teeth. Group A
served as an unbleached group and group B,C,D and E were treated using 15% carbamide peroxide gel.
Following this, group C, D and E were exposed to Coca-Cola once, twice and thrice respectively, at 6 hourly
interval by immersing the samples in 32.5 ml of Coca- Cola. This entire procedure was carried out for 7 days
and the surface morphological changes of enamel were examined under SEM. Morphological changes on
enamel surface were evaluated using Yeh et al (2005)modification of Hobson’s acid-etch pattern on enamel.
Results: In comparison to group A, statistically significant values were found in group B (p=0.037), C
(p=0.027), D (p=0.011) and statistically more significant value in group E(p=0.004).Further,in relation to
group B, statistically significant value was observed only in group E (p=0.025).
Conclusion: From the present study, it can be concluded that 15% carbamide peroxide gel causes significant
morphological alterations on enamel surfaces. These alterations were increased further by the exposure to
carbonated beverage Coca-Cola especially with the increase in the number of exposures to Coca-Cola.