Oral Leukoplakia (OL) is a term describing the white lesions of the oral mucosa; it is the most common potentially malignant lesion of the oral cavity. The epidemiology of this condition in Arab countries is not well studied. A computer-based search for literature through pub-med was performed using relevant keywords to retrieve studies conducted in Arab world related to OL. After searching PubMed database, local journals and cross-referencing; a total of 12 articles were used for this review. Eight studies were cross-sectional, of them, two studies estimated a prevalence that ranged between 1.9% and 3.6%. Studies about various risk factors and prognostic marker were conducted in a clinical setting using case-control design (n=4). Cultural determinants such as certain smokeless tobacco habits (e.g. Qat and Shammah chewing) and Cigarette smoking were among factors investigated in some Arab countries. The results demonstrate a strong relationship between OL and Qat and Shammah Chewing (OL prevalence was 22-27% among tobacco users). Further population-based studies should be conducted in Arab countries to identify a causal relationship between these factors and the development, onset and progression of OL.

Keywords: Oral leukoplakia; Arab; epidemiology; premalignant; prevalence.

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Zainah Alshehri

Ministry of Health, Quality Coordinator