title: Bisphosphonates and osteonecrosis of the jaw: a retrospective study.
abstract: OBJECTIVE
  To assess the prevalence of osteonecrosis of the jaw (ONJ) in patients receiving bisphosphonate therapy and in those who were bisphosphonate naïve.
  
  
  METHODS
  We undertook a retrospective review of medical records of patients at the New York Harbor Health Care System from 1999 through 2004. Charts were selected for review if patients had a Current Procedural Terminology (CPT) code suggestive of ONJ or if they had ever received bisphosphonate therapy.
  
  
  RESULTS
  Among 1,951 medical records reviewed, we identified 2 patients with ONJ who had received bisphosphonates and 2 patients with ONJ who were bisphosphonate naïve. Both patients treated with bisphosphonates had multiple myeloma and were receiving monthly infusions. They had initially received pamidronate before treatment was changed to zoledronic acid. In each case, ONJ was precipitated by a routine dental extraction. The prevalence of ONJ in our patient population receiving intravenously administered bisphosphonates was 1 in 71.5. Of the 2 cases of ONJ in bisphosphonate-naïve patients, osteoradionecrosis was clearly incriminated in 1 patient and potentially the causative factor in the other patient as well. No patients receiving orally administered bisphosphonates had ONJ, nor did this complication occur in any patients receiving parenteral bisphosphonate therapy for disorders such as osteoporosis or Paget's disease of bone.
  
  
  CONCLUSIONS
  Bisphosphonates remain an important option for management of metabolic bone disease and complications of malignant disease. The overall prevalence of ONJ in patients receiving bisphosphonates seems to be very low; however, patients receiving intense parenteral therapy for an underlying malignant condition appear to have a uniquely elevated risk for the development of this complication. A causal relationship between bisphosphonates and ONJ remains to be proved and merits further investigation.
authors.affiliation: Division of Endocrinology, Elkhart Clinic and Elkhart General Hospital, Elkhart, Indiana.
authors.forename: Omar M
authors.initials: OM
authors.lastname: Murad
authors.forename: Surender
authors.initials: S
authors.lastname: Arora
authors.forename: Amal F
authors.initials: AF
authors.lastname: Farag
authors.forename: Helena A
authors.initials: HA
authors.lastname: Guber
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019386:Alendronate / Q000009:adverse effects; D050071:Bone Density Conservation Agents / Q000009:adverse effects*; D001847:Bone Diseases / Q000188:drug therapy; D004164:Diphosphonates / Q000009:adverse effects*; D012968:Etidronic Acid / Q000009:adverse effects / Q000031:analogs & derivatives; D006801:Humans; D007093:Imidazoles / Q000009:adverse effects; D007571:Jaw Diseases / Q000139:chemically induced*; D008297:Male; D008875:Middle Aged; D010020:Osteonecrosis / Q000139:chemically induced*; D000077268:Pamidronate; D015995:Prevalence; D012189:Retrospective Studies; D000068296:Risedronic Acid; D014505:Urban Population; D000077211:Zoledronic Acid
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D007093:Imidazoles; D000077211:Zoledronic Acid; D000068296:Risedronic Acid; D012968:Etidronic Acid; D000077268:Pamidronate; D019386:Alendronate