The use of tobacco, in smoking and smokeless forms, is known to cause lesions, that is notorious and may lead to oral cancer. Studies show that the risk of developing oral cancer is 5-9 times greater for tobacco consumers than non-consumers. The high mortality rate of this dreaded disease might be reduced by its early detection and treatment. The oral epithelial cells represent a preferred target site for early genotoxic events induced by agents. Similarly, the urothelial cells may represent a possible target for absorbed and excreted mutagens of tobacco. Exfoliative cytology, is a technique developed to supplement clinical examination in cancer diagnosis, as it is quick, simple and non-invasive. Among the various early detection tools, the use of the Micronucleus assay in exfoliated cells has been well documented to determine the chromosomal damage and mutagenic influence on the mucosa. The main aim of this study is to develop the use of Micronucleus assay in exfoliated cells, as a procedure to detect early genotoxic changes caused by smoking and smokeless tobacco associated habits.