Notizen: Background:  Information on alcohol-associated oral mucosal lesions (OMLs) and conditions is meagre. A prevalence survey among alcohol misusers in south London was therefore undertaken.Methods:  Six hundred and ninety-three subjects (388 alcohol misusers and 305 alcohol + substance abuse) attending several clinical care facilities in south London between 1994 and 1999 were interviewed on their alcohol and drug habits. A comprehensive oral mucosal examination was performed, and soft tissue lesions found were classified by the clinical criteria of Axéll.Results:  Mean age of the sample was 40.5 years. The majority was white (92.6%); of the whites, 29.9% were Celts (i.e. Irish, Scots resident in London). Many subjects reported misusing more than one type of beverage. Two hundred and twenty-seven OMLs were found in 195 subjects (28.1%). The highest prevalences were found for frictional keratosis (8.8%), scar tissue of the lips (4.8%) and candidiasis (3.8%). Angular cheilitis was present in 21 subjects (3.0%). The alcohol-related OMLs detected were three white patches compatible with a diagnosis of leukoplakia and one treated oral carcinoma. No erythroplakias were detected. The differences in prevalence of mucosal lesions in the two groups were not significant (χ2 = 2.18; P = 0.14). The prevalence of tobacco smoking was high in both study groups. OMLs were found with all four types of beverages consumed, and there was little variation by the units per week consumed. Concurrent use of substances and alcohol did not make a significant difference to the prevalence of OML. In the logistic regression analysis, minority ethnic groups (Black or Asian), smokers, those with a body mass index (BMI) under 20 and beer drinkers had an increased risk of an OML in this group of alcohol misusers.Conclusions:  In comparison with previous oral mucosal screening programmes undertaken in several settings in the UK, the present study has yielded a higher prevalence of oral mucosal diseases and conditions in this risk population. There are several ways in which alcohol could contribute to these detected oral lesions, either directly or indirectly.