Behavior of patients with autistic syndrome makes delivery of oral hygiene and dental treatment a problem. In this study, the oral health and needs of two groups of patients with autism were evaluated: noninstitutionalized children with a mean age of 11 and institutionalized adults with a mean age of 22. The latter group had severe periodontal problems; almost half required periodontal surgery. Many of the children also needed periodontal treatment. Adults were found to have lower decayed, missing, and filled teeth (DMFT) scores than functionally independent Israeli persons of the same age. This finding was surprising because institutionalized adults are predisposed to development of dental caries; they frequently consume sweets, have poor oral hygiene, and do not use fluoride. Noninstitutionalized children with autism had caries rates that were similar to rates of functionally independent peers.