title: Three-dimensional assessment of mandibular and glenoid fossa changes after bone-anchored Class III intermaxillary traction.
abstract: BACKGROUND
  Conventional treatment for young Class III patients involves extraoral devices designed to either protract the maxilla or restrain mandibular growth. The use of skeletal anchorage offers a promising alternative to obtain orthopedic results with fewer dental compensations. Our aim was to evaluate 3-dimensional changes in the mandibles and the glenoid fossae of Class III patients treated with bone-anchored maxillary protraction.
  
  
  METHODS
  Twenty-five consecutive skeletal Class III patients between the ages of 9 and 13 years (mean age, 11.10 ± 1.1 year) were treated with Class III intermaxillary elastics and bilateral miniplates (2 in the infrazygomatic crests of the maxilla and 2 in the anterior mandible). The patients had cone-beam computed tomography images taken before initial loading and at the end of active treatment. Three-dimensional models were generated from these images, registered on the anterior cranial base, and analyzed by using color maps.
  
  
  RESULTS
  Posterior displacement of the mandible at the end of treatment was observed in all subjects (posterior ramus: mean, 2.74 ± 1.36 mm; condyles: mean, 2.07 ± 1.16 mm; chin: mean, -0.13 ± 2.89 mm). Remodeling of the glenoid fossa at the anterior eminence (mean, 1.38 ± 1.03 mm) and bone resorption at the posterior wall (mean, -1.34 ± 0.6 mm) were observed in most patients.
  
  
  CONCLUSIONS
  This new treatment approach offers a promising alternative to restrain mandibular growth for Class III patients with a component of mandibular prognathism or to compensate for maxillary deficiency in patients with hypoplasia of the midface. Future studies with long-term follow-up and comparisons with facemask and chincup therapies are needed to better understand the treatment effects.
authors: Department of Orthodontics, School of Dentistry, University of North Carolina, Chapel Hill, NC, USA. hugo.declerck@skynet.be
authors: Hugo
authors: H
authors: De Clerck
authors: Tung
authors: T
authors: Nguyen
authors: Leonardo Koerich
authors: LK
authors: de Paula
authors: Lucia
authors: L
authors: Cevidanes
mesh_terms: D000293:Adolescent; D001860:Bone Plates; D016723:Bone Remodeling / Q000502:physiology; D001862:Bone Resorption / Q000473:pathology; D002508:Cephalometry / Q000379:methods*; D002648:Child; D002680:Chin / Q000473:pathology; D054893:Cone-Beam Computed Tomography / Q000379:methods; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008313:Malocclusion, Angle Class III / Q000628:therapy*; D008334:Mandible / Q000473:pathology*; D008335:Mandibular Condyle / Q000473:pathology; D008437:Maxilla / Q000473:pathology; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation / Q000379:methods*; D009967:Orthodontic Appliances; D011446:Prospective Studies; D013701:Temporal Bone / Q000473:pathology*; D014143:Traction / Q000295:instrumentation; D014584:User-Computer Interface