This study aimed to assess the oral health status of individuals with schizophrenia and explore its association with behavioural and pharmacological factors, with particular focus on long-term antipsychotic treatment and cumulative anticholinergic burden.

A total of 153 adults with schizophrenia (18–65 years) from the Mental Health Network of Bizkaia (Spain), all under antipsychotic treatment for ≥12 months, were evaluated and compared with 153 controls from the general population. Data on socio-demographic variables, tobacco use and oral hygiene habits were collected. Oral health was assessed using the Decayed, Missing and Filled Teeth (DMFT) index and the Community Periodontal Index of Treatment Needs (CPITN). Unstimulated salivary flow was measured, and subjective xerostomia symptoms were recorded. Cumulative anticholinergic burden was estimated using the Drug Burden Index, considering both psychotropic and non-psychotropic medications. The association between dental health and clinical, behavioural and pharmacological variables was analysed in patients with schizophrenia.

Patients with schizophrenia exhibited significantly poorer oral health than controls, with higher mean DMFT scores (15.3 vs. 10.9; p < 0.001) and more advanced periodontal disease indicated by CPITN. Salivary hypofunction (<0.45 ml/min) was present in 31% of patients versus 12% of controls. In addition, high to very high anticholinergic burden was present in 71.9% of patients with schizophrenia, compared to only 3.3% of controls. In patients with schizophrenia, multivariate analyses identified the following as significant predictors of worse dental status (DMFT): age; smoking; female sex; illness duration; reduced salivary flow; poor tooth brushing; and anticholinergic burden. For periodontal health (CPITN), however, no variable was identified as a significant predictor of high-risk periodontal status.

Oral health is substantially compromised in individuals with schizophrenia, reflecting a multifactorial interplay of behavioural, systemic and pharmacological factors. Both cumulative anticholinergic burden and reduced salivary flow independently contribute to poorer dental health, while periodontal disease appears to result from more complex influences not fully captured with studied variables. These findings underscore the importance of proactive clinical strategies, including regular dental assessments, targeted oral hygiene interventions, interdisciplinary collaboration between mental health and dental care providers and careful review of psychopharmacological regimens to minimize unnecessary anticholinergic exposure. Such integrated approaches are essential to preserve oral health, enhance quality of life and improve long-term outcomes in this vulnerable population.