Evaluation of the Effects of Various Types of Mouthwash on Enamel and Cementum of Permanent Teeth: An In Vitro Study

Background: Mouthwashes are widely utilised for their affordability, ease of use and oral hygiene benefits. However, indiscriminate use of these over-the-counter mouthwashes can cause morphological changes in enamel and cementum, compromising tooth structure. This study evaluates the change in the surface roughness, surface hardness and colour of enamel and cementum after the use of various mouthwashes using surface profilometry, Vickers hardness tester and spectrophotometry, respectively, for 7 and 15 days. Materials and Methodology: Five common mouthwashes, namely, Colgate Plax, Listerine, Himalaya, Chlorhexidine and warm saline water were tested on 10 extracted permanent teeth in each group. Teeth were sectioned longitudinally from crown to root, embedded in acrylic and examined for defects. Baseline values for colour, hardness and roughness were recorded before immersing the samples in mouthwash as per the manufacturers’ instructions. Postimmersion measurements were taken at specified intervals. Results: A significant decrease in enamel hardness after 7 days with chlorhexidine (108.28 ± 85.17), Himalaya (104.02 ± 94.22), warm saline (85.42 ± 70.9) and Listerine (55.32 ± 83.68) was observed, but not with Colgate Plax. Cementum hardness decreased over 15 days but was not statistically significant. The greatest increase in surface roughness was seen in saline followed by Himalaya whereas the decrease was seen in chlorhexidine and Colgate Plax at the end of 7 days. Listerine caused the highest colour change in enamel. Since trends towards decreased hardness and increased roughness were noted, long-term usage could pose clinical concerns. Warm saline showed subtle yet significant changes, indicating the need for further investigation. Conclusion: These findings underscore the importance of regulating mouthwash use and recommending it only when the benefits outweigh the risks.