To assess the methodological quality of epidemiological studies on dental pain and review the published literature for its prevalence, and association with age, gender and socio-economic status. Medline and reference lists of relevant articles were searched for observational studies published in English from 1966 to 2001 carried out on humans aged 19 years and over. Articles for reading of the full text were selected by two reviewers independently. Selected articles were assessed independently by the two reviewers according to a set of 8 standardized criteria. Inter-rater agreement was measured using the kappa statistic. Disagreements were discussed and a final score for each study agreed. Data on prevalence estimates and their distribution by age, gender and socio-economic factors were extracted. 422 studies were identified, and 23 selected for review. Inter-rater agreement was high for all 8 criteria used (kappa > 0.6). Methodological quality was poor with the number of criteria fulfilled by each study ranging from 1 to 6, median score 3. The prevalence estimates for 5 case definitions identified were: 'toothache' 7-32%, 'pain in teeth with hot, cold or sweet things' 25-38%, 'pain and discomfort needing medication or treatment' 7-9%, 'pain or discomfort in the mouth, teeth or gums' 19-66%, and 'oral and facial pain'40-44%. Younger subjects and those from lower socio-economic groups were more likely to report pain. Gender was not associated with dental pain. Epidemiological data on dental pain are sparse and of poor quality. There is a need for well-designed surveys using randomly selected community samples and standardized measurement criteria to fill this knowledge gap.