Background:
Oral cancer is a major public health problem among Paniya tribes, a marginalized tribal group in Kerala state, South India. Previous studies have documented a high prevalence of tobacco chewing habit among Paniya tribals in Wayanad. Precancerous lesions of oral mucosa, known as potentially malignant disorders are consists of a group of diseases, which should be diagnosed in the early stage. The aim of this study was to evaluate the risks imposed by tobacco chewing in the development of oral cancer.

Methods:
A cross-sectional descriptive study was conducted to assess tobacco chewing and precancerous oral lesions prevalence among 600 Paniya tribes in the Wayanad District,India. Information on tobacco chewing status, type , quantity and duration of chewing was collected from cases and controls using a questionnaire.Inhabitants of the villages aged 18 to 65 years who were residing for more than 10 years were included. All the examinations were performed by a single examiner. Data was collected using a survey proforma which comprised of a questionnaire and WHO Oral Health Surveys (1997). The collected data was subjected to statistical analysis.

Results:
In this study precancerous lesions were found to be far more prevalent among chewing Paniya tribes than among the controls(P < 0.0001). The prevalence of precancerous oral lesions were higher among tobacco chewers (18.9%,95%,CI 16.5-20.9). This was much higher than found among the non chewer(0.8%,95 CI 0.6-1.3). Among the tobacco chewers a statistically significant relationship was observed between precancerous lesions and poor access to health care (P< 0.001).

Conclusions:
Prevalence of precancerous oral lesions in the study population was due to tobacco usage and lack of awareness regarding the deleterious effects of the products used. Regular oral examination by dental professionals, dental health education and motivation to maintain oral hygiene should be insisted to improve the oral health status of this community.