title: Comparison of craniofacial growth of untreated Class I and Class II girls from ages 9 to 18 years: a longitudinal study.
abstract: BACKGROUND
  The purposes of this study were to examine and compare the craniofacial growth in girls with Class I or Class II occlusion from the ages of 9 to 18.
  
  
  METHODS
  Twenty-five Class I (ANB, 1°-4°) and 21 Class II (ANB, >4°) untreated Caucasian girls were selected from the Burlington Growth Centre in Toronto, Ontario, Canada. Cephalograms of each subject at ages 9, 14, and 18 years were traced, and 29 parameters were measured. The growth changes in each parameter from ages 9 to 14, 14 to 18, and 9 to 18 were calculated, and comparisons of each parameter were made between the 2 groups.
  
  
  RESULTS
  From ages 9 to 14, the Class I and Class II groups had similar skeletal growth patterns (increases of SNA and SNB angles, decreases of ANB, MP-SN, and gonial angles). Dentally, the Class II group showed less maxillary incisal proclination and more overbite than did the Class I group. From ages 14 to 18, the 2 groups also showed similar growth patterns, with little sagittal but continued vertical growth, and the MP-SN angle continued to decrease. From ages 9 to 18 (combined periods of 9-14 and 14-18), the 2 groups showed similar skeletal growth, with the exception of a slightly higher ANS-ME/N-Me in the Class I group. Dental changes were similar in the 2 groups, except that overbite increased slightly more in the Class II group.
  
  
  CONCLUSIONS
  Overall, the craniofacial growth patterns of Class I and Class II girls were similar. With growth, the face became more flattened with a decrease of the ANB angle, and the mandible demonstrated forward rotation with decreases of the MP-SN and gonial angles, and an increase of PFH:AFH.
authors: Private practice, San Francisco, Calif.
authors: Sarah S
authors: SS
authors: Yoon
authors: Chauncey M. F. Egel Endowed Chair and associate professor, Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pa. Electronic address: chunc@dental.upenn.edu.
authors: Chun-Hsi
authors: CH
authors: Chung
mesh_terms: D000293:Adolescent; D002508:Cephalometry / Q000379:methods; D002648:Child; D002680:Chin / Q000254:growth & development; D005147:Facial Bones / Q000254:growth & development*; D005260:Female; D006801:Humans; D007180:Incisor / Q000033:anatomy & histology; D008137:Longitudinal Studies; D008311:Malocclusion, Angle Class I / Q000503:physiopathology*; D008312:Malocclusion, Angle Class II / Q000503:physiopathology*; D008334:Mandible / Q000254:growth & development; D008437:Maxilla / Q000254:growth & development; D008445:Maxillofacial Development / Q000502:physiology; D009295:Nasal Bone / Q000254:growth & development; D057887:Overbite / Q000503:physiopathology; D012399:Rotation; D012658:Sella Turcica / Q000254:growth & development; D012886:Skull / Q000254:growth & development*; D019291:Skull Base / Q000254:growth & development; D014716:Vertical Dimension