Background Many psychological disorders are associated with comorbid physical illness. There are less data on dental disease in common psychological disorders such as depression and anxiety in spite of risk factors in this population of diet, lifestyle or antidepressant-induced dry mouth.

Methods We undertook a systematic search for studies of the oral health of people with common psychological disorders including depression, anxiety and dental phobia. We searched MEDLINE, PsycInfo, EMBASE and article bibliographies. Results were compared with the general population. Outcomes included partial or total tooth-loss, periodontal disease, and dental decay measured through standardized measures such as the mean number of decayed, missing and filled teeth (DMFT) or surfaces (DMFS).

Results There were 19 papers on depression and/or anxiety, and seven on dental phobia/anxiety (total n=26). These covered 334,503 subjects. All the psychiatric diagnoses were associated with increased dental decay on both DMFT and DMFS scores, as well as greater tooth loss (OR=1.22; 95%CI=1.14–1.30). There was no association with periodontal disease, except for panic disorder.

Limitations Cross-sectional design of included studies, heterogeneity in some results, insufficient studies to test for publication bias.

Conclusion The increased focus on the physical health of psychiatric patients should encompass oral health including closer collaboration between dental and medical practitioners. Possible interventions include oral health assessment using standard checklists that can be completed by non-dental personnel, help with oral hygiene, management of iatrogenic dry mouth, and early dental referral. Mental health clinicians should also be aware of the oral consequences of inappropriate diet and psychotropic medication.