Background: Research on the dental health of people with intellectual disability has consistently reported more untreated dental disease, more extractions and fewer fillings than in the general population. This paper describes the oral health of participants at the 2005 Glasgow Special Olympics (SO), relating this to the general population studied in the 1998 UK Adult Dental Health Survey (ADHS) and to participants' age and region of residence. Methods: Consenting SO participants were offered oral examinations which followed the standardized SO protocol plus an innovative soft tissue examination. Urgency of any treatment required was noted and reported to participants and carers. Three measures of good dental health--having 21 or more natural teeth, absence of fillings and having no obvious untreated decay--were compared across age groups, regions and with the general population. Logistic regression was used to control for age differences between regions. Results: In total, 1021 oral examinations were completed. Older SO participants were more likely to have fewer than 21 teeth and to have fillings, untreated decay, gum inflammation and heavy plaque levels. In all, 28% of SO participants had 21 or more teeth, no fillings and no obvious decay. Those from the north, midlands and south regions of England had significantly more chance of good dental health so defined compared with participants from Scotland [ORs 1.67 (1.09, 2.67), 1.69 (1.12, 2.54), 1.99 (1.26, 3.16), respectively]. Compared with the general population surveyed in the 1998 ADHS study, SO participants were more likely to be free from fillings and obvious untreated decay, but fewer had 21 or more natural teeth among older age groups. Nine per cent were found to have soft tissue problems, and one in four of these required follow-up. Gum inflammation was common. Overall, 5% of participants were judged to require urgent treatment for dental or soft tissue problems and 40% to require non-urgent treatment. This rose to 9% and 66% respectively among those aged 35 years and over. Discussion: The low prevalence of untreated decay and fillings among SO participants compared with the general population may be due to their being well supported by family and carers. The study identifies the vulnerability of the older participants to dental problems, and this may indicate greater difficulty maintaining surveillance as individuals age or informal carers become less able or available. Regional variations are similar to those found in the general population. The implications for the organization of care for this group are discussed. (Contains 1 figure and 2 tables.)