BackgroundThe oral health of patients with severe mental illness is poor, in general, and this may be attributed, in part, to inadequate dental care. This study investigated dental care utilization among patients with severe mental illness using a national representative sample.MethodsThis study used Taiwan’s National Health Insurance Research Dataset for 2009. Patients with the diagnosis of severe mental illness (ICD-9-CM: 290–298) were recruited as the study sample, and others comprised the control. Any visit to a dentist was defined as positive in terms of dental care utilization. Regression analyses were applied to determine the odds of dental care utilization for each diagnostic entity of severe mental illness, compared with the general population and controlling for potential covariates.ResultsOnly 40 % of 19,609 patients with severe mental illness visited the dentist within 12 months. This was significantly lower than the dental visit rate of 48.3 % for the control population (odds ratio [OR] = .72, 95 % confidence interval [CI] = .69–.74; P <0.0001). The odds of dental care utilization differed among the severe mental illness diagnostic categories; e.g., the odds were lowest among those with alcohol psychoses (OR = .54, CI = .43–.68), senile dementia (OR = .55, CI = .52–.59) and other organic psychoses (OR = .58, CI = .52–.65), and highest among those with mood disorder (OR = .89, CI = .85–.94), with schizophrenic patients occupying a mid-level position (OR = .63, CI = .59–.67).ConclusionsPatients with severe mental illness received less dental care than the general population. Health care providers and caregivers of patients with severe mental illness should encourage them to visit the dentist regularly, in order to improve the oral health of these vulnerable patient groups.