Evaluation of genotoxic effect of amalgam restorations in oral cavity

Abstract

Background: Mercury a popular heavy metal used in dentistry in the form of amalgam is a known clastogen. The assessment of micronuclei in cells is a promising tool for studying the genotoxic effect of mercury on them. Hence, a study was conducted to evaluate the frequency of micronuclei in exfoliated buccal cells of subjects with amalgam restorations. Materials and Methods: A total of 60 subjects (age and gender-matched sample of 30 study group and 30 control group) were included in this study. Smears were obtained with moistened wooden spatula from buccal mucosa in close contact with amalgam restoration and fixed with 100% ethyl alcohol. After staining with Papanicolaou stain, all the slides were examined under ×40 and 1,000 cells were counted for the presence of micronuclei. The data were entered into a spread sheet and subjected to statistical analysis. Results: A statistically significant increase in the number of micronuclei containing cells was observed in the study group when compared to control group (P < 0.05). A positive correlation was observed between the duration of restoration and frequency of micronuclei (P < 0.05). Conclusion: The results showed a definite genotoxic effect of amalgam restorations on the oral cavity which can be attributed to the clastogenic action of mercury in amalgam restorations.

Keywords

• Amalgam, biocompatibility, genetics, genotoxicity, mercury, micronuclei, Papanicolaou stain