Introduction This study aimed to assess the prevalence and nature of oral health impacts on daily life and examine the relationship between psychiatric symptoms, oral health problems, and oral health related quality of life (OHRQoL) in individuals with severe psychiatric and/or substance use disorders. Methods Data were collected from a cross-sectional study of 138 adult inpatients (median age 35.5 years, range 19–70, 60% men, 40% women) at the Division of Mental Health and Substance Use, University Hospital of Northern Norway. Participants underwent clinical oral examinations including radiographs. A structured questionnaire covered various health domains, including oral health. The primary outcome was OHRQoL, assessed by the Oral Impact on Daily Performance (OIDP) questionnaire. Data were analyzed with descriptive statistics, cross-tabulations, regression analysis, and Hayes' PROCESS Macro v4.2 (Model 4) for simple mediation analyses. Results Problems with at least one of the activities assessed with the OIDP questionnaire were reported by 72.3% of the participants with more than 60% having issues at least weekly. Most common were problems with eating (54.4%), cleaning- or showing teeth (40.0%), and sleeping (35.8%). Mediation analyses showed that general health, psychological distress, and (prodromal or current) psychosis symptoms were directly linked to OIDP. Tooth decay and missing teeth were independently associated with OIDP, while subjective symptoms including orofacial pain and xerostomia showed patterns consistent with indirect associations. Discussion This study found a strong association between oral problems and quality of life among adults facing severe psychiatric and/or substance use disorders. The activities most often affected by oral problems were eating, showing teeth, tooth cleaning and sleeping, which are important for both physical and mental health. These findings underscore the importance of integrated, interdisciplinary oral health care in psychiatric- and substance use services to address pain and tooth loss to improve quality of life.
Kantola et al. (2026) studied this question.