title: Anatomic factors related to bisphosphonate osteonecrosis of the jaws: a Portuguese retrospective study.
abstract: OBJECTIVE
  The objectives of this study of bisphosphonate-related osteonecrosis of the jaws (BRONJ) were to determine local distribution, possible anatomically associated or determinant factors and other bone involvement of the disease, contributing with this new data towards the establishment of its prevalence in Portugal.
  
  
  METHODS
  The authors made a retrospective study of patients presenting BRONJ, at the Department of Stomatology of Santa Maria University Hospital, in Lisbon (42 cases) from 1st January 2004, to April 30rd, 2011. SPSS Statistics was implemented.
  
  
  RESULTS
  There was a higher prevalence of lesions in the lower jaw (66.7%), compared to the upper jaw (26.19%) and a significantly higher occurrence in alveolar bone (95.24%). The molars and premolars were the most affected areas (highest value at 6th sextant = 35.29%). In all cases, the onset of injury occurred after a medication period of up to 90 days, spontaneously in 14.29% of patients.
  
  
  CONCLUSIONS
  For severity, BRONJ was a significant anatomoclinical entity in all 42 new cases in this study, and for discomfort (pain) in 81.1% of them. There was an anatomic correlation between the occurrence of the disease and its location in the jaws. There was a clinical association with trauma and type, route and length of administration of the bisphosphonate, with Zoledronate being administered intravenously in 76.19% of the cases. The jaws were the unique place where the disease occurred. Preventive measures should be implemented, avoiding trauma, and performing surgical procedures within 90 days after prescription.
authors.affiliation: Institute of Anatomy of Lisbon Medical Faculty & Santa Maria University Hospital, Lisbon, Portugal.
authors.forename: Ivo
authors.initials: I
authors.lastname: Álvares Furtado
authors.forename: Cecília
authors.initials: C
authors.lastname: Franco Caldas
authors.forename: Fernanda
authors.initials: F
authors.lastname: Lança
authors.forename: Francisco
authors.initials: F
authors.lastname: Salvado e Silva
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D059266:Bisphosphonate-Associated Osteonecrosis of the Jaw / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011174:Portugal; D012189:Retrospective Studies