Byline: Anne-Marie Bollen (1), Akira Taguchi (2), Philippe P. Hujoel (3), Lars G. Hollender (4) Keywords: Alveolar bone; Dental; Fractures; Panoramic radiograph; Teeth Abstract: The purpose of this case-control study was to determine if elderly subjects with a history of osteoporotic fractures have fewer teeth and greater residual ridge resorption than subjects without such fractures. Patients older than 60 with a panoramic radiograph were invited to a phone interview. Information was obtained regarding fracture history, smoking, and hormone replacement therapy (HRT). The number of teeth was obtained from the panoramic radiograph. The residual ridge height of the edentulous mandible was measured at the site of the mental foramen. Multiple regression models were used to assess the association between fracture status and number of teeth or residual ridge height (controlling for age, gender, HRT, smoking, height and weight). Cases (n=93) were individuals reporting osteoporotic fractures (fractures occurring after minor impact). Controls (n=394) were individuals reporting traumatic fractures (n=105) or no fractures (n=289). Fracture status in this population affect neither the number of teeth nor the residual ridge height. In the regression model, the variables that had a statistically-significant effect on the number of teeth were age (p< 0.0001) and smoking (p< 0.0001). There was a dose-effect of smoking on the number of teeth. In the regression model, the variables that had a significantly-significant on residual ridge height (n=95 edentulous subjects) were age and gender. Our conclusion was that in elderly dental-school patients the number of teeth and residual ridge height were not influenced by fracture status. Age and smoking had the most influence there was no effect from HRT. The clinical implication is that a history of osteoporotic fractures is not an important cause for tooth loss and residual ridge resorption in an elderly dental-school population. Author Affiliation: (1) Department of Orthodontics, School of Dentistry, University of Washington, Box 357446, Seattle, WA 98195, USA (2) Department of Oral and Maxillofacial Radiology, School of Dentistry, Hiroshima University, Hiroshima, Japan (3) Dental Public Health Sciences, School of Dentistry, University of Washington, Seattle, WA 98195, USA (4) Department of Oral Medicine, School of Dentistry, University of Washington, Seattle, WA 98195, USA Article History: Registration Date: 25/06/2004 Received Date: 12/11/2002 Accepted Date: 20/03/2003 Online Date: 09/09/2004