title: [Comparison of closing T loop technique and sliding technique using preadjusted appliance].
abstract: OBJECTIVE
  To compare the difference between closing T loop technique and sliding technique. In anchorage demand and treatment outcome.
  
  
  METHODS
  Sixteen first premolar extraction cases were chosen and divided into two groups for prospective paired t-test. They were treated by one author using 0.022" x 0.028" preadjusted appliances. T loops were fabricated using 0.018" x 0.025" s.s. wire. Chinese NiTi coil springs and 0.019" x 0.025" s.s. arch wire were employed in sliding technique group. Treatment materials, steps and appliance design in both groups were standardized. Measurements of dental model and cephalogram were taken.
  
  
  RESULTS
  In closing T loop technique group and sliding technique group, the ratio of anterior teeth movement was 0.55 and 0.53 respectively. The difference was not significant (P > 0.05). L1MP angle decreased by 5.7 degrees and 3.1 degrees respectively during treatment (P < 0.05).
  
  
  CONCLUSIONS
  Demand on anchorage was not significantly different between two groups. Sliding technique was more favorable in maintaining anterior teeth inclination.
authors.affiliation: Beijing Hospital of Stomatology, Capital University of Medical Sinence, Beijing 100050.
authors.forename: X
authors.initials: X
authors.lastname: Yang
authors.forename: X
authors.initials: X
authors.lastname: Zeng
mesh_terms: D000293:Adolescent; D000328:Adult; D001641:Bicuspid / Q000601:surgery; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D009967:Orthodontic Appliances; D009971:Orthodontics, Corrective / Q000295:instrumentation / Q000379:methods*; D014081:Tooth Extraction