The aim of this multicentre case-control study was to investigate the association of a variety of factors with oral cancer in a group of Turkish patients. Questionnaires were used to investigate the sociodemographic features, smoking and alcohol consumptions, dietary habits and dental status of 79 primary oral cancer patients and 61 controls. Data were statistically analysed with Mann-Whitney U-test, Pearson Chi-square and binary logistic regression analyses to determine the odds ratios. Low level of education, gender, dietary habits, having poor oral hygiene and denture sores were associated with primary oral cancer in this patient sample; but eating salads and raw vegetables, fish, and drinking red wine were related with healthy status. Determination of the factors associated with oral cancer and of the high-risk groups would be beneficial to provide efficient screening protocols and prevention programmes for oral cavity cancers. (c) 2005 Elsevier Ltd. All rights reserved.