Prevalence of temporomandibular disorder signs in patients with schizophrenia

The aim of this study was to determine the prevalence of temporomandibular disorder (TMD) signs in a group of institutionalized patients with schizophrenia. Three hundred thirty-nine patients with schizophrenia were examined and compared with 107 age-matched and gender-matched control subjects. TMD signs were evaluated according to the Research Diagnostic Criteria to assess temporomandibular joint pain to palpation, limitation of maximum mouth opening, alteration of mouth opening pathway (deviation/deflection) and temporomandibular joint noises. In addition, tooth wear was recorded for the assessment of bruxism. The prevalence of any TMD signs was observed higher (P = 0.001) in the patients with schizophrenia (284/339, 83.7%) than in the controls (72/107, 67.3%). The prevalence of more than one TMD sign was also significantly higher (P = 0.03) in the patients with schizophrenia (131/339, 38.6%) than in the controls (29/107, 27.1%). Significant differences between the two groups were apparent for joint pain on palpation (P = 0.006), deflection (P = 0.006) and joint sounds (P = 0.002). Severe tooth wear was evident in 39.2% of the patients with schizophrenia compared with 21.2% in the control group (P = 0.001). The finding of the present study showed that, compared to control population, chronically hospitalized patients with schizophrenia seem to be more prone to the development of TMD signs and severe tooth wear and bruxism.