1. Division of Community Oral Health Development; Kyushu Dental University; Kitakyushu Japan
2. Department of Preventive and Restorative Dental Sciences; University of California San Francisco; San Francisco CA USA
3. Department of Comprehensive Education; Kyushu Dental University; Kitakyushu Japan
4. Department of Oral Microbiology; Matsumoto Dental University; Shiojiri Japan
5. Kokura Daiichi Hospital; Kitakyushu Japan