1. Dr. Takarada is Assistant Professor, Division of General Oral Care, Kyushu University Hospital, Fukuoka, Japan; Dr. Asada is a Postgraduate Student, Division of General Oral Care, Kyushu University Hospital, Fukuoka, Japan; Dr. Sumi is Research Associate, Division of General Oral Care, Kyushu University Hospital, Fukuoka, Japan; and Dr. Higuchi is Professor, Division of General Oral Care, Kyushu University Hospital, Fukuoka, Japan