Loss of underlying supportive alveolar bone is a major cause of tooth loss. Alveolar bone loss appears to be related to the status of the extracranial skeleton, and therapies that preserve skeletal bone may be expected to benefit tooth retention. An association between postmenopausal hormone replacement therapy (HRT) and tooth retention was found in a cohort of 488 elderly women, 72 to 95 years old, who participated in the Framingham Heart Study between 1948 and 1995. There was an association between duration of HRT and tooth retention for total number of teeth remaining and the individual types of teeth (incisors, canines, and premolars, but not molars) retained. The odds of being edentulous were reduced by 6% for each 1-year increase in duration of HRT use. The data suggest that postmenopausal HRT protects against tooth loss and reduces the risk of edentulism.