title: A histochemical study on condylar cartilage and glenoid fossa during mandibular advancement.
abstract: OBJECTIVE
  To evaluate cellular hypertrophic activities in the mandibular condylar cartilage (MCC) and the glenoid fossa (GF) during mandibular advancement in the temporomandibular joint (TMJ) of Sprague-Dawley rats, as evidenced by fibroblast growth factor 8 (FGF8).
  
  
  METHODS
  Fifty-five female 24-day-old Sprague-Dawley rats were randomly divided into four experimental and control groups, with a mandibular advancement appliance on the experimental rats' lower incisors. The rats were euthanized on days 3, 14, 21, and 30 of the study, and their TMJ was prepared for a immunohistochemical staining procedure to detect FGF8.
  
  
  RESULTS
  FGF8 expression was significantly higher among the experimental rats (P  =  .002). Patterns of ascension and descension of FGF8 expression were similar in experimental and control samples. The results show an overall enhanced osteogenic transition occurring in both the MCC and the GF in experimental rats in comparison with controls. The level of cellular changes in the MCC is remarkably higher than in the GF.
  
  
  CONCLUSIONS
  In the MCC and the GF, cellular morphologic and hypertrophic differentiations increase significantly during mandibular advancement. It is also concluded that endochondral ossification in the MCC and intramembranous ossification in the GF occur during adaptive remodeling.
authors.affiliation: Department of Orthodontics, University of Sydney, Sydney Dental Hospital, NSW Australia.
authors.forename: Payam
authors.initials: P
authors.lastname: Owtad
authors.forename: Zoe
authors.initials: Z
authors.lastname: Potres
authors.forename: Gang
authors.initials: G
authors.lastname: Shen
authors.forename: Peter
authors.initials: P
authors.lastname: Petocz
authors.forename: M Ali
authors.initials: MA
authors.lastname: Darendeliler
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D016723:Bone Remodeling; D002358:Cartilage, Articular / Q000378:metabolism / Q000473:pathology; D020219:Chondrogenesis; D005260:Female; D051524:Fibroblast Growth Factor 8 / Q000096:biosynthesis*; D006984:Hypertrophy / Q000473:pathology; D019186:Mandibular Advancement; D008335:Mandibular Condyle / Q000378:metabolism / Q000473:pathology; D010012:Osteogenesis; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013701:Temporal Bone / Q000378:metabolism / Q000473:pathology; D013704:Temporomandibular Joint / Q000378:metabolism* / Q000473:pathology*
chemical_list: D051524:Fibroblast Growth Factor 8