Root resorption in permanent teeth is a frequently observed pathology that may originate in various causes. Life expectancy is progressively rising, odontological preventive care is becoming more widespread and professionals are educating their patients in the importance of preventive practices. Because senior citizens are thus losing fewer teeth prematurely they will be conversely more at risk for dental problems later in life. The knowledge of the alterations that may appear in the roots of geriatric patients is particularly relevant to devising therapy and establishing prognosis. The aim of the present study was to evaluate the nature and magnitude of the histologic and histomorphometric features of root resorption and the eventual possibility of repair in elderly people. Seventy-seven uniradicular teeth of patients aged between 65 and 90 years and 18 premolars of patients aged between 14 and 20 years, were removed, fixed in 90% formalin, decalcified in EDTA and embedded in paraffin. Vestibulo-lingual sections were stained with hematoxylin-eosin and employed to perform histological and histomorphometric studies. The results showed that 30% of the teeth of younger patients and 94% of the teeth of elderly patients exhibited areas of root resorption. From the 416 resorptive areas found in elderly patients, 173 exhibited signs of repair being the volume/surface ratio of these areas 0.69 +/- 0.06. These data show that root resorption is a frequent finding in the older population under study. Resorptions are characterized by scarce depth, large areas and a high incidence of repair despite the old age of the patients.