Cytogenetic Alterations in Oral Potentially Malignant Disorders Associated with Chronic Mechanical Irritation: A Comparative Analysis of Micronuclei, Silver-Stained Nucleolar Organiser Count and Comet Assays.

BACKGROUND: Chronic mechanical irritation (CMI) of the oral mucosa has been suggested as a potential cofactor for oral cancer (OC) as a dependent risk factor. OC could be preceded by oral potentially malignant disorders (OPMDs), and early detection can improve prognosis. The prevalence of genetic damage among the OPMD individuals associated with and without CMI remains unexplored. OBJECTIVES: The objective is to assess genetic damage in oral exfoliative cells of CMI-associated individuals presenting with and without OPMD using micronuclei count, argyrophilic nucleolar organizing region (AgNOR) count, and comet assay. MATERIALS AND METHODS: Micronucleus assay, AgNOR assay, and comet assay analysis were performed in a total sample of 75 individuals grouped as control (n = 25), CMI without OPMD (n = 25), and CMI with OPMD (n = 25). RESULTS: A significant increase in DNA damage is not only found in CMI with OPMD group, but also in CMI without OPMD, where chronic irritation can act as an independent factor in causing DNA damage. CONCLUSION: CMI could cause permanent DNA damage and is considered a low-risk factor in cancer development.