Affiliation: | 1. Division of Oral Medicine and Pathology, Department of Human Biology and Pathophysiology, Health Sciences University of Hokkaido, Ishikari‐Tobetsu, Hokkaido, Japan;2. Division of Disease Control and Molecular Epidemiology, Department of Oral Growth and Development, Health Sciences University of Hokkaido, Ishikari‐Tobetsu, Hokkaido, Japan |