1. Dental Practice and Rural Health, School of Dentistry, 104A Health Sciences Center Addition, P.O. Box 9448, Morgantown, WV 26506, USA
2. Department of Periodontics, School of Dentistry, Division of Dental Hygiene, West Virginia University, Robert C Byrd Health Sciences Center North, Room 1192A, Morgantown, WV 26506, USA
3. Department of Periodontics, School of Dentistry, West Virginia University, Robert C Byrd Health Sciences Center North, P.O. Box 9490, Room 1070, Morgantown, WV 26506, USA