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Dental conditions in inpatients with schizophrenia: A large-scale multi-site survey

Hideaki Tani1, Hiroyuki Uchida12*, Takefumi Suzuki1, Yumi Shibuya3, Hiroshi Shimanuki4, Koichiro Watanabe15, Ryosuke Den6, Masahiko Nishimoto7, Jinichi Hirano5, Hiroyoshi Takeuchi1, Shintaro Nio18, Shinichiro Nakajima1, Ryosuke Kitahata8, Takashi Tsuboi19, Kenichi Tsunoda10, Toshiaki Kikuchi1 and Masaru Mimura1

Author Affiliations

1 Department of Neuropsychiatry, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan

2 Geriatric Mental Health Program, Centre for Addiction and Mental Health, 1001 Queen Street West, Toronto, ON M6J 1 H4, Canada

3 Department of Dentistry, Bright Dental Care, 1-65 Namikimotomachi, Kawaguchi-shi, Saitama, 332-0033, Japan

4 Department of Dentistry, Sakuragaoka Memorial Hospital, 1-1-1 Renkouji, Tama-shi, Tokyo, 206-0021, Japan

5 Department of Psychiatry, Ohizumi Hospital, 6-9-1 Ohizumigakuennchou, Nerima-ku, Tokyo, 178-0061, Japan

6 Department of Psychiatry, Komagino Hospital, 273 Uratakaomachi, Hachiouji-shi, Tokyo, 193-8505, Japan

7 Department of Psychiatry, Touyokokeiai Hospital, 4-17-23 Arima, Miyamae-ku, Kawasaki-shi, Kanagawa, 216-0003, Japan

8 Department of Psychiatry, Tokyo Musashino Hospital, 4-11-11 Komone, Itabashi-ku, Tokyo, 173-0037, Japan

9 Department of Psychiatry, Nakayama Hospital, 2-10-2 Nakayama, Ichikawa-shi, Chiba, 272-0813, Japan

10 Department of Psychiatry, Minamihannou Hospital, 415 Yaoroshi, Hannou-shi, Saitama, 357-0042, Japan

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BMC Oral Health 2012, 12:32  doi:10.1186/1472-6831-12-32

Published: 18 August 2012



Clinical relevance of dental caries is often underestimated in patients with schizophrenia. The objective of this study was to examine dental caries and to identify clinical and demographic variables associated with poor dental condition in patients with schizophrenia.


Inpatients with schizophrenia received a visual oral examination of their dental caries, using the decayed-missing-filled teeth (DMFT) index. This study was conducted in multiple sites in Japan, between October and December, 2010. A univariate general linear model was used to examine the effects of the following variables on the DMFT score: age, sex, smoking status, daily intake of sweets, dry mouth, frequency of daily tooth brushing, tremor, the Clinical Global Impression-Schizophrenia Overall severity score, and the Cumulative Illness Rating Scale for Geriatrics score.


523 patients were included in this study (mean ± SD age = 55.6 ± 13.4 years; 297 men). A univariate general linear model showed significant effects of age group, smoking, frequency of daily tooth brushing, and tremor (all p’s < 0.001) on the DMFT score (Corrected Model: F(23, 483) = 3.55, p < 0.001, R2 = 0.42) . In other words, older age, smoking, tremor burden, and less frequent tooth brushing were associated with a greater DMFT score.


Given that poor dental condition has been related with an increased risk of physical co-morbidities, physicians should be aware of patients’ dental status, especially for aged smoking patients with schizophrenia. Furthermore, for schizophrenia patients who do not regularly brush their teeth or who exhibit tremor, it may be advisable for caregivers to encourage and help them to perform tooth brushing more frequently.

Aging; Dental caries; Schizophrenia; Smoking; Tooth brushing; Tremor