[1] Univ Washington, Dept Periodont, Seattle, WA 98195 USA
[2] Univ Washington, Dept Oral Med, Seattle, WA 98195 USA
[3] Univ Washington, Dept Oral Maxillofacial Surg, Seattle, WA 98195 USA
[4] Univ Washington, Inst Aging, Seattle, WA 98195 USA
[5] Univ British Columbia, Div Prosthodont, Vancouver, BC V5Z 1M9, Canada