Objective: A number of studies have evaluated the oral health of patients with autism spectrum disorder (ASD), though most have involved children, and no specific oral manifestations have been described. The present study describes the buccodental disorders and hygiene habits in a group of adults with ASD. Study Design: A prospective case-control study was made of a group of patients with ASD (n=30), with a mean age of 27.7±5.69 years, and of a healthy age- and gender-matched control group (n=30). An evaluation was made of the medical history, medication, oral hygiene habits and oral diseases, with determination of the CAOD, CAOS and OHI-S oral hygiene scores. Results: Most of the patients in the ASD group used two or more drugs and were assisted in brushing 2-3 times a day. The most frequent manifestations were bruxism, self-inflicted oral lesions and certain malocclusions. The CAOD and CAOS scores were significantly lower than in the controls. Conclusions: Adults with ASD and assisted dental hygiene presented fewer caries than the non-disabled population. However, bruxism, ogival palate and anterior open bite were frequent in the patients with ASD. Key words:Autism spectrum disorder, caries, dental hygiene, oral manifestations.