Rui Egashira1, Yojiro Umezaki2, Shinsuke Mizutani3, Toyoshi Obata4, Masahiro Yamaguchi1, Keiko Tamai1, Mizuki Yoshida1, Michiko Makino5, Toru Naito1. 1. Section of Geriatric Dentistry, Department of General Dentistry, Fukuoka Dental College, Fukuoka, Japan. 2. Section of Geriatric Dentistry, Department of General Dentistry, Fukuoka Dental College, Fukuoka, Japan. Electronic address: umezaki@college.fdcnet.ac.jp. 3. Section of Geriatric Dentistry and Perioperative Medicine in Dentistry, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyusyu University, Fukuoka, Japan; OBT Research Center, Faculty of Dental Science, Kyushu University, Fukuoka, Japan. 4. Obata Medical Clinic, Fukuoka, Japan. 5. The Center for Visiting Dental Service, Fukuoka Dental College, Fukuoka, Japan.
Abstract
BACKGROUND AND AIM: Recent shifts in the distribution of Japan's population towards older ages, have meant that the chance of encountering patients with dementia in dental clinics is increasing. Many studies have shown that the brain volume decreases along with the progression of dementia. Although previous studies have reported a relationship between tooth loss or periodontitis and the onset of dementia, the pathological mechanisms underlying this association have not been elucidated. In this study, we aimed to examine the relationship between the oral condition and brain atrophy and to discuss how to adequately deal with patients with dementia. PARTICIPANTS AND METHODS: This cross-sectional study included 15 participants who underwent brain magnetic resonance imaging (MRI). The participants were 60 years or older and presented with cognitive decline, including Alzheimer's disease (AD) and mild cognitive impairment (MCI), diagnosed by a neurologist. We obtained information on the oral condition, lifestyle, cognitive function, and brain atrophy. Cognitive function was assessed using the Mini-Mental State Examination (MMSE). MR images of each patient were analyzed using the voxel-based specific regional analysis system for Alzheimer's disease (VSRAD) to provide a quantitative measure of the degree of brain atrophy. RESULTS: The study population included 4 male and 11 female patients. The mean age and mean number of present teeth were 75.9 years (SD 6.7) and 15.0 (SD 11.1), respectively. The median MMSE score was 25.6 (SD 3.7). The degree of atrophy of the whole brain was significantly correlated with the number of present teeth (ρ = -0.72, p < 0.05) and the presence of a daily exercise habit (ρ = -0.66, p < 0.05). CONCLUSION: This study demonstrated that the number of present teeth could be an indicator of the progress of dementia. Preserving the teeth as well as the acquisition of a regular exercise habit might be important for preventing progression of dementia. Further research examining a larger study population and analyzing a greater number of factors is warranted.
BACKGROUND AND AIM: Recent shifts in the distribution of Japan's population towards older ages, have meant that the chance of encountering patients with dementia in dental clinics is increasing. Many studies have shown that the brain volume decreases along with the progression of dementia. Although previous studies have reported a relationship between tooth loss or periodontitis and the onset of dementia, the pathological mechanisms underlying this association have not been elucidated. In this study, we aimed to examine the relationship between the oral condition and brain atrophy and to discuss how to adequately deal with patients with dementia. PARTICIPANTS AND METHODS: This cross-sectional study included 15 participants who underwent brain magnetic resonance imaging (MRI). The participants were 60 years or older and presented with cognitive decline, including Alzheimer's disease (AD) and mild cognitive impairment (MCI), diagnosed by a neurologist. We obtained information on the oral condition, lifestyle, cognitive function, and brain atrophy. Cognitive function was assessed using the Mini-Mental State Examination (MMSE). MR images of each patient were analyzed using the voxel-based specific regional analysis system for Alzheimer's disease (VSRAD) to provide a quantitative measure of the degree of brain atrophy. RESULTS: The study population included 4 male and 11 female patients. The mean age and mean number of present teeth were 75.9 years (SD 6.7) and 15.0 (SD 11.1), respectively. The median MMSE score was 25.6 (SD 3.7). The degree of atrophy of the whole brain was significantly correlated with the number of present teeth (ρ = -0.72, p < 0.05) and the presence of a daily exercise habit (ρ = -0.66, p < 0.05). CONCLUSION: This study demonstrated that the number of present teeth could be an indicator of the progress of dementia. Preserving the teeth as well as the acquisition of a regular exercise habit might be important for preventing progression of dementia. Further research examining a larger study population and analyzing a greater number of factors is warranted.