Analysis of genetic damage in individuals exposed to Chronic Mechanical Irritation (CMI) in the lateral border of the tongue due to Cusp of Carabelli (CoC) –A Cytogenetic study

Background: Chronic inflammation is estimated to contribute to approximately 25% of human cancers. Inflammation that is induced by chronic mechanical irritation (CMI) along with carcinogens has a higher chance of leading to oral pre-cancer and oral cancer. Though many studies have been conducted to identify the genetic damage in oral cancer or dysplastic stages, there is no study conducted to find the early detection of genetic damage in healthy individuals associated with CMI. Cusp of Carabelli (CoC) is a small additional cusp at the mesiopalatal line angle of maxillary first molars which can cause chronic irritation to the lateral border of the tongue.  Objective: The study is aimed to analyze genetic damage (micronuclei and nuclear buds) in healthy individuals associated with CoC over the lateral border of the tongue causing CMI. Materials and methods: The study comprised of 75 clinically healthy individuals with unilateral/bilateral presence of CoC causing irritation over the lateral border of the tongue as study group. Brush samples of lesional epithelial cells were collected, then spread over clean glass slide and fixed in 100% alcohol, stained with rapid PAP and analyzed under the light microscope. The exfoliated cells were examined to detect the presence of micronuclei (MN). Results: Incidence of MN was found to be more in CoC associated lateral border of the tongue of healthy individuals without habits. Conclusions: Cytogenetic analysis is a simple and scantly invasive technique allowing clinicians in early detection of DNA damage in patients with CoC and preventing the carcinogenesis by proper treatment and follow-up.