title: The orthopaedic effects of bone-anchored maxillary protraction in a beagle model.
abstract: OBJECTIVE
  The purpose of this study was to establish an animal model of bone-anchored maxillary protraction (BAMP) and verify the effects of such treatment in this model.
  
  
  METHODS
  Ten total immature (90-day-old) male beagle dogs were used. On Day -20, one miniplate per jaw quadrant was placed and secured with screws. From Day 0 to Day 60, miniplates in the dogs in the intermaxillary traction group (group T, n = 5) were loaded with coil springs. In the control group (group C, n = 5), the miniplates received no force. Every 20 days from Day -20, all dogs were assessed by measuring body weight, taking photographs, and acquiring standardized lateral cephalometric radiographs using a specially designed cephalostat. Cephalometric analyses were performed and the two groups compared. New bone formation was labelled by double-fluorochrome administration with calcein and tetracycline. Animals were sacrificed at Day 60, and bone sections of zygomaticomaxillary sutures were analysed using histomorphometry with fluorescence microscopy. Groups were compared with Mann-Whitney U-tests (P < 0.05).
  
  
  RESULTS
  Cephalometric analysis indicated significant maxillary advancement and retroclination of maxillary incisors in group T, with concomitant significant posterior relocation of the condyles and proclination of the mandibular incisors. In histological analysis, vigorous bone apposition at the zygomaticomaxillary suture was only detected in group T.
  
  
  CONCLUSIONS
  Further histological studies would clarify the effects of BAMP on the mandible, especially on temporomandibular articulation.
  
  
  CONCLUSIONS
  Our results, using this newly developed animal model, support the orthopaedic effects of BAMP.
authors.affiliation: Section of Maxillofacial Orthognathics, Department of Maxillofacial Reconstruction and Function, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Ito
authors.affiliation: Section of Maxillofacial Orthognathics, Department of Maxillofacial Reconstruction and Function, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan t-kawamoto.mort@tmd.ac.jp.
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Kawamoto
authors.affiliation: Section of Maxillofacial Orthognathics, Department of Maxillofacial Reconstruction and Function, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Keiji
authors.initials: K
authors.lastname: Moriyama
mesh_terms: D000818:Animals; D001860:Bone Plates; D002508:Cephalometry / Q000379:methods; D003393:Cranial Sutures / Q000473:pathology; D004195:Disease Models, Animal; D004285:Dogs; D007180:Incisor / Q000473:pathology; D008297:Male; D008313:Malocclusion, Angle Class III / Q000628:therapy*; D008334:Mandible / Q000473:pathology; D008437:Maxilla / Q000473:pathology; D052280:Orthodontic Anchorage Procedures / Q000379:methods*; D010155:Palatal Expansion Technique