1. Department of Geriatric Dentistry, Osaka Dental University, 2-2-14 Higashitanabe, Higashisumiyoshi-ku, Osaka 546-0032, Japan
2. Nogami Dental Office, 4-22-18 Nishiimagawa, Higashisumiyoshi-ku, Osaka 546-0042, Japan
3. Fukuoka Dental Office, 704-4 Torai, Satsuma-gun, Kagoshima 895-1811, Japan
4. Section of Oral Implantology, Department of Oral Rehabilitation, Fukuoka Dental College, 2-15-1 Tamura, Sawara-ku, Fukuoka 814-0193, Japan
5. The Center for Visiting Dental Service, Department of General Dentistry, Fukuoka Dental College, 2-15-1 Tamura, Sawara-ku, Fukuoka 814-0193, Japan
6. Bees Dental Office, 6-904 Befudanchi, Jyonan-ku, Fukuoka 814-0106, Japan