title: Do Class III patients have a different growth spurt than the general population?
abstract: BACKGROUND
  Understanding the timing and length of the growth spurt of Class III prognathic patients is fundamental to the strategy of interceptive orthopedic orthodontics as well as to the timing of orthognathic surgery. Consequently, this study was undertaken to determine whether there are any significant differences in the stature growth pattern of Class III subjects compared with non-Class III subjects and the general population.
  
  
  METHODS
  Twelve-year longitudinal stature growth data were collected for 402 randomly selected adolescents in the general population, 55 Class III mandibular prognathic patients, and 37 non-Class III patients. The growth data were analyzed by using the traditional linear interpolation method and nonlinear growth functions. The 6 stature growth parameters were measured: age at takeoff, stature at takeoff, velocity at takeoff, age at peak height velocity, stature at peak height velocity, and velocity at peak height velocity. Comparisons in the stature growth parameters and 15 cephalometric variables among the general population, Class III subjects, and non-Class III subjects were made with multivariate analysis.
  
  
  RESULTS
  Patients with Class III prognathism did not have different growth parameters compared with Class II subjects or the general population.
  
  
  CONCLUSIONS
  This study does not allow meaningful conclusions with regard to the relationship of mandibular size and stature growth pattern. The application of nonlinear growth curves vs the traditional linear interpolation method was also discussed.
authors.affiliation: Department of Orthodontics, School of Dentistry and Dental Research Institute, Seoul National University, Seoul, Korea.
authors.forename: Yun-Sik
authors.initials: YS
authors.lastname: Lee
authors.forename: Shin-Jae
authors.initials: SJ
authors.lastname: Lee
authors.forename: Hongseok
authors.initials: H
authors.lastname: An
authors.forename: Richard E
authors.initials: RE
authors.lastname: Donatelli
authors.forename: Soo-Hwan
authors.initials: SH
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D001827:Body Height / Q000502:physiology*; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008313:Malocclusion, Angle Class III / Q000503:physiopathology*; D008334:Mandible / Q000033:anatomy & histology / Q000254:growth & development* / Q000473:pathology; D008445:Maxillofacial Development; D015999:Multivariate Analysis; D017711:Nonlinear Dynamics; D011378:Prognathism / Q000503:physiopathology*; D012015:Reference Standards; D012016:Reference Values; D012680:Sensitivity and Specificity