Oral bisphosphonate-associated osteonecrosis of the jaw after implant surgery: a case report and literature review.

This report documents a case of bisphosphonate-related osteonecrosis of the jaw (BRONJ) after dental implant placement in an osteoporotic patient treated with alendronate for 6 years. A 63-year-old patient underwent rehabilitation of the posterior mandible with 2 dental implants in 2006 while taking alendronate to treat osteoporosis. The surgical procedure was uneventful. Both implants integrated well, and in November 2006 the patient wore a fixed partial prosthesis. Alendronate was never discontinued. In June 2008 a painful cheek swelling of the left mandible developed, associated with gingival bleeding. Since then, the patient underwent several courses of antibiotics, without relief of symptoms. In June 2009 the patient was referred to our department. An area of infected and exposed necrotic bone in the left mandible enclosed 1 dental implant. A panoramic radiograph and computed tomography scan showed an increased bone marrow density with peri-implant bone sequestration. The technetium Tc 99m scintigraphy-labeled granulocytes were positive for active bone infection. Bone exposure persisted for 8 weeks, and diagnosis of oral nitrogen-containing bisphosphonate (N-BP)-related osteonecrosis was made. On the basis of a review of the literature, this is the 10th case of BRONJ after implant placement in patients taking oral N-BPs. Despite the low risk of BRONJ occurrence after implant surgery in oral N-BP users, the fate of dental implants in these patients remains uncertain. Therefore patients at risk must be given a full explanation of the potential risks of implant failure and BRONJ development. Because the potential role of infection is still debated, great attention should be paid to the long-term oral hygiene of implant-prosthetic restorations.
(Copyright 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)