title: Histochemical observation of bony reversal lines in bisphosphonate-related osteonecrosis of the jaw.
abstract: OBJECTIVE
  To contrast the pattern of bony reversal linesin bisphosphonate osteonecrosis of the jaw with infected osteomyelitis derived acute osteonecrosis of the jaw.
  
  
  METHODS
  This study investigated the histochemical characteristics of reversal lines in 50 cases of BP-related osteonecrosis of the jaw (BRONJ) compared with non-BP-involved bones in 20 cases of chronic osteomyelitis of the jaws. Necrotic bones were stained by using the toluidine blue, Safranin O, Giemsa, van Gieson, and Masson's trichrome staining methods.
  
  
  RESULTS
  All BP-involved bones in BRONJ were distinguishable from non-BP-involved bones in chronic osteomyelitis of the jaws by multiple thick, irregular, reversal lines, which were strongly stained with toluidine blue, Safranin O, and Giemsa solution. The reversal lines of BP-involved bones (average 31.2 ± 10.85 μm) were thicker than those of osteomyelitic bones (average 11.1 ± 3.76 μm), and they were closely associated with immature bony matrices containing collagenous materials positive for van Gieson and Masson's trichrome staining with statistical significance (P = .0212 in t test statistics). The immature reversal lines of BP-involved bones continuously appeared as thick non-birefringence lines between lamellate structures as observed under a polarizing microscope, whereas the reversal lines of non-BP-involved bones were gradually thinned as their mineralization advanced.
  
  
  CONCLUSIONS
  BP-involved bones had immature bony matrices outlined by thick reversal lines, which might be crucial to rapid osteonecrosis of BRONJ and also could be hallmarks for the differential diagnosis of BRONJ from chronic osteomyelitis of the jaws.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Dental Research Institute, School of Dentistry, Seoul National University, Seoul, Korea.
authors.forename: Soung Min
authors.initials: SM
authors.lastname: Kim
authors.affiliation: Department of Oral and Maxillofacial Surgery, Dental Research Institute, School of Dentistry, Seoul National University, Seoul, Korea.
authors.forename: Mi Young
authors.initials: MY
authors.lastname: Eo
authors.affiliation: Department of Dental Hygiene, Cheongju University, Cheongju, Korea.
authors.forename: Yeon Sook
authors.initials: YS
authors.lastname: Kim
authors.affiliation: Department of Oral Pathology, College of Dentistry, Gangneung-Wonju National University, Gangneung, Korea. Electronic address: Sukkeunlee@hanmail.net.
authors.forename: Suk Keun
authors.initials: SK
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D059266:Bisphosphonate-Associated Osteonecrosis of the Jaw / Q000473:pathology*; D050071:Bone Density Conservation Agents / Q000009:adverse effects*; D002908:Chronic Disease; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010019:Osteomyelitis / Q000473:pathology; D013194:Staining and Labeling
chemical_list: D050071:Bone Density Conservation Agents