title: Epidemiology, pharmacology and clinical characterization of bisphosphonate-related osteonecrosis of the jaw. A retrospective study of 70 cases.
abstract: OBJECTIVE
  Bisphosphonates are widely prescribed drugs whose principal capacity is inhibiting the osteoclast function. In 2003 a complication related to their administration, bisphosphonate-related osteonecrosis of the jaw (BRONJ), was described. The objectives of this study were to identify diagnosed cases of BRONJ in a third-level hospital over 8 years, evaluating the main features in relation to the disease, the bisphosphonate and the presence of local or general risk factors that could trigger the BRONJ.
  
  
  METHODS
  Patients diagnosed with BRONJ in a centre of reference for a population of 1,100,000 inhabitants were selected. Variables analysed were classified into 3 groups: patients, bisphosphonate (focusing on dose and weighting dose/potency) and osteonecrosis.
  
  
  RESULTS
  Seventy cases were studied -44 women and 26 men-, with a mean age of 66.8 years. Eighteen patients received bisphosphonates orally and 52, intravenously. The mean time of administration was 26.53 months. In 67.1% of the patients it was possible to identify a local trigger, with the most common being tooth extraction (48.6%). Bone exposure was present in 89.2% of the cases, while 12 patients developed BRONJ without exposed bone, with only pain and/or chronic sinus tracts. Complete resolution was achieved in 58.6% of the patients, with a mean time of control of 16.28 months.
  
  
  CONCLUSIONS
  25% of the BRONJ cases were related to the administration of oral bisphosphonates, especially alendronate. Zoledronic acid was the bisphosphonate that required the fewest milligrams to induce osteonecrosis. Single bone exposure was the most common clinical finding, especially in the molar mandibular region in patients with metastatic disease.
authors.affiliation: Servicio de Cirugía Oral y Maxilofacial, Hospital de Cabueñes, Gijón, Asturias, España.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Pelaz
authors.affiliation: Servicio de Cirugía Oral y Maxilofacial, Hospital Universitario Central de Asturias, Universidad de Oviedo, Oviedo, España. Electronic address: Junquera@uniovi.es.
authors.forename: Luis
authors.initials: L
authors.lastname: Junquera
authors.affiliation: Servicio de Cirugía Oral y Maxilofacial, Hospital de Cabueñes, Gijón, Asturias, España.
authors.forename: Lorena
authors.initials: L
authors.lastname: Gallego
authors.affiliation: Servicio de Cirugía Oral y Maxilofacial, Hospital Universitario Central de Asturias, Universidad de Oviedo, Oviedo, España.
authors.forename: Luis
authors.initials: L
authors.lastname: García-Consuegra
authors.affiliation: Escuela de Enfermería, Universidad de León, Hospital de León, León, España.
authors.forename: Lucía
authors.initials: L
authors.lastname: García-Martínez
authors.affiliation: Servicio de Cirugía Maxilofacial, Universidad de L'Aquila, L'Aquila, Italia.
authors.forename: Tommaso
authors.initials: T
authors.lastname: Cutilli
authors.affiliation: Universidad de Oviedo, Oviedo, España.
authors.forename: Sonsoles
authors.initials: S
authors.lastname: Olay
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019386:Alendronate / Q000008:administration & dosage / Q000009:adverse effects; D059266:Bisphosphonate-Associated Osteonecrosis of the Jaw / Q000453:epidemiology* / Q000209:etiology / Q000473:pathology*; D004164:Diphosphonates / Q000008:administration & dosage / Q000009:adverse effects; D012968:Etidronic Acid / Q000008:administration & dosage / Q000009:adverse effects; D005260:Female; D006801:Humans; D007093:Imidazoles / Q000008:administration & dosage / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D013030:Spain / Q000453:epidemiology; D062606:Tertiary Care Centers; D000077211:Zoledronic Acid
chemical_list: D004164:Diphosphonates; D007093:Imidazoles; D000077211:Zoledronic Acid; D012968:Etidronic Acid; D019386:Alendronate
keywords: Bisfosfonatos; Bisphosphonates; Bone exposure; Exposición ósea; Osteonecrosis de los maxilares; Osteonecrosis of the jaw