title: [The effect of the position of artificial premature on mandible moving track during opening movement].
abstract: OBJECTIVE
  The purpose of this study was to observe the effect of the position of premature on track of mandibular incisal point during opening movement.
  
  
  METHODS
  The changes of the track of mandibular incisal point along with the change of premature position were recorded by Arcus DigMa mandibular moving track analysis system. The relativity between the premature position and mandibular incisal point moving track on arrowy axis, vertical axis and horizontal axis was analyzed. Regression analysis was used for linear correlation between premature position and mandible opening moving track.
  
  
  RESULTS
  The results showed that along with the retrusion of premature, the moving distance of mandibular incisal point tended to increase on arrowy axis, while decrease on vertical axis and lean to the contralateral side on horizontal axis. The linear regression equation of mandibular incisal point moving distance on vertical axis along with the premature position was: y=34.7095-0.1590x(1), delta=0.5549, P<0.001.
  
  
  CONCLUSIONS
  The position of premature influenced the track of mandibular incisal point during opening movement significantly. With the retrusion of premature, the mandible opening moving track tended to be more posterior and shifting to the contralateral side, and the opening dimension tended to decrease. There was linear correlation between premature position and mandible moving track on the vertical axis.
authors.affiliation: Department of Prosthodontics, College of Stomatology, Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200011, China.
authors.forename: Hui-juan
authors.initials: HJ
authors.lastname: Cheng
authors.forename: Yu-qin
authors.initials: YQ
authors.lastname: Chen
authors.forename: Yi
authors.initials: Y
authors.lastname: Geng
authors.forename: Fu-qiang
authors.initials: FQ
authors.lastname: Zhang
mesh_terms: D003766:Dental Occlusion; D006801:Humans; D007180:Incisor; D007574:Jaw Relation Record; D008334:Mandible / Q000502:physiology*; D009068:Movement