A retrospective study of the effects of edentulism on the severity rating of tardive dyskinesia.

Edentulism has been reported to be a risk factor in the development of spontaneous orofacial dyskinesia. This study aimed to determine whether edentulism increases the severity rating of tardive dyskinesia in psychiatric subjects treated with neuroleptic medication. The filed Abnormal Involuntary Movement Scale reports of 84 edentulous and 109 dentate outpatients with schizophrenic or schizoaffective disorder were examined retrospectively. To compare dyskinesia ratings in different body areas with dental status and gender, 2 x 2 multivariate analysis of variance was used. Results show that edentulous subjects had significantly higher dyskinesia ratings in the orofacial categories but not in other body areas. Gender had no influence on dyskinesia ratings. These results indicate that tooth loss may considerably increase the severity of tardive dyskinesia, a finding that suggests a possible role of preventive and prosthetic dentistry in the health care of patients at risk for this condition.