Evaluation of oral tissues and dentition abnormalities among schizophrenia

Objectives:

Several previous reports suggest that patients with schizophrenia have an increased prevalence of developmental abnormalities in the teeth than those of non-psychiatric controls. Because the face and the brain develop in concern with the same ectodermal tissues, the study of abnormalities of oral tissues and teeth may give clues to brain developmental processes underpinning schizophrenia. As one test of this hypothesis, we decided to examine the oral tissues and dentition in patient with schizophrenia versus control group.

Methods:

The sample consisted of 75 patients with schizophrenia, 26 female and 49 male (mean age 35.1 years) and 65 non-psychiatric controls, 32 female and 33 male (mean age 32.6). A standardized set of record was obtained from each individual, including a detailed clinical examination and panoramic radiograph. Blind to group membership, the developmental abnormalities of the number, size, shape and structure of teeth, tongue, tempromandibular joint were assessed by a dentist. Besides, the cephalic and facial index was measured using a 25-cm head and neck caliper. The data were analyzed by Chi-square and Fisher's exact test.

Results:

Our results show a notably high prevalence of congenital missing third molar, microdontia of maxillary first molar as well as peg lateral, macrodontia of mandibular first and second premolar, underdevelopment of carabelli cusp, dentinogenesis imperfecta, short mid-face height, broad face, anterior lower spacing, generalized attrition and tempromandibular joint disorders in patients with schizophrenia in comparison with the control subjects.

Conclusion:

Our findings reveal that a defect in brain development may have influenced the development of oral tissues as well as teeth, and therefore the abnormalities we found are not independent of brain development. In addition, these abnormalities of oral tissues and teeth may serve as a marker to determine the time at which abnormal development first begins in schizophrenia.