This study examines the prevalence of oral mucosal lesions and conditions among Irish addiction treatment centre residents and explores the feasibility and acceptability of a targeted oral cancer screening programme for such individuals. Four alcohol addiction treatment centres were visited periodically over a 12-month period. Two hundred and twenty residents (78% of 283 targeted) were interviewed regarding their alcohol, tobacco and drug habits (type, quantity, duration), and attitudes to dental care. Comprehensive oral examinations were performed. All potentially sinister soft tissue lesions/symptoms were referred for further investigation. Data analysis utilised SPSS-18. Ten participants who denied a history of alcohol/drug addiction were excluded from the main study. Remaining 210 participants comprised 148 males (70%) and 62 females (30%), ranging from 18 to 73 years of age, (mean 37.65; S. D. 13.82); 60% were under 40. High rates of tobacco and alcohol usage were recorded, 53% reported dual addiction (drug + alcohol), 44% alcohol only, 3% drug only. The prevalence of mucosal abnormalities was 29% with 84 mucosal abnormalities/symptoms detected in 61 subjects, comprising 28 extra-oral lesions/symptoms and 56 intra-oral lesions. Residents with mucosal abnormalities were significantly older (mean 41.8 years; S. D. 14.3) than those without such lesions (mean 35.95; S. D. 13.3), (p < 0.05). Highest prevalences were noted for candidiasis (3.8%), facial scaring/laceration (3.8%), intra-oral lumps/swellings (2.9%), lymphadenopathy (2.9%) and hoarseness (1.9%). Four red areas suggestive of erythroplasia and two leukoplakic lesions were detected. Study addresses the paucity of data on the prevalence of oral mucosal lesions in addicted persons in Southern Ireland. Thirteen extra-oral lesions/symptoms and 19 intra-oral lesions were potentially significant. Despite the relatively poor follow-up compliance rate (33%), two premalignant lesions were confirmed in the main study group, yielding a detection rate of 0.9%. Results suggest that an oral cancer screening programme targeted at individuals in addiction treatment centres may provide a feasible way to access persons with a history of tobacco and alcohol abuse. A high rate of untreated disease and emergency only attendance was seen in this study suggesting a lack of engagement with GDP services. Opportunistic screening in primary care is therefore unlikely to capture this cohort. Inclusion of oral cancer screening in the routine medical examination given to residents of addiction treatment centres may provide an efficient and effective way to detect potentially malignant lesions in these high-risk individuals. (C) 2011 Elsevier Ltd. All rights reserved.