title: [Treatment of maxillary protrusion in adult with self-tapping micro-screw implants].
abstract: OBJECTIVE
  To investigate the position change of upper molars and incisors in order to evaluate the stability of posterior anchorage with the application of micro-screw implant.
  
  
  METHODS
  Eight adult patients with severe maxillary protrusion were included. Upper first premolars were extracted and upper posterior anchorage was reinforced with micro-screw implant in all patients. Cephalometric and cast analyses were carried out to record the position change of molar and micro-screw.
  
  
  RESULTS
  During treatment the micro-screw implants kept stable in sagittal and vertical plane. Neither the mesial-distal movement nor the tipping of the upper molars during the treatment was statistically significant (P > 0.05). The edge of upper incisors was retracted by 6.86 mm and the tipping was reduced by 18.03 degrees . The center of resistance was intruded by 3.28 mm on average. Significant change was observed (P < 0.01).
  
  
  CONCLUSIONS
  Micro-screw implant could provide good anchorage control in the orthodontic treatment.
authors.affiliation: Department of Orthodontic, Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou 510055, China. fzcu2@tom.com
authors.forename: Da-wei
authors.initials: DW
authors.lastname: Wang
authors.forename: Zhi-cai
authors.initials: ZC
authors.lastname: Feng
authors.forename: Shuang-lin
authors.initials: SL
authors.lastname: Zhu
authors.forename: Xin-hua
authors.initials: XH
authors.lastname: Lu
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008310:Malocclusion / Q000628:therapy*; D052280:Orthodontic Anchorage Procedures; D016896:Treatment Outcome; D055815:Young Adult