title: Comparison of intrusion effects on maxillary incisors among mini implant anchorage, j-hook headgear and utility arch.
abstract: BACKGROUND
  Intrusion of maxillary incisors is one of the most important and difficult tooth movements to achieve as a part of orthodontic therapy. A variety of techniques were used in the past to intrude the maxillary incisors before the emergence of mini implants in Orthodontics. Mini implants are temporary anchorage devices used to produce various tooth movements. The research was carried out to evaluate and compare the efficiency of producing intrusion of maxillary incisors using mini implants, utility arch and j- hook headgear.
  
  
  METHODS
  The study was conducted on 30 subjects divided into 3 Groups equally. Group 1- mini implant anchorage, Group 2 - j- hooks headgear and Group 3- utility arch were used for intrusion of the maxillary incisors. Conventional lateral cephalograms were taken before treatment and at the end of intrusion. Five cephalometric parameters were used to measure the amount of intrusion attained in each Group. Intra Group comparisons were done using student t-test and inter Group comparisons were done using ANOVA The duration of intrusion was four months in all the three Groups.
  
  
  RESULTS
  In Group 1 the mean average intrusion attained was 2.1 mm, the mean average intrusion attained in Group 2 was 0.7 mm, and the mean average intrusion achieved in Group 3 was 1.4 mm with a side effect of 0.75 mm of molar extrusion.
  
  
  CONCLUSIONS
  Although, both mini implants and utility arch can be used to attain significant amounts of incisor intrusion but using mini implants will produce true intrusion without any other side effects.
authors.affiliation: Senior Lecturer, Department of Orthodontics, College of Dental Surgery, Saveetha University , Chennai, India .
authors.forename: Ravindra Kumar
authors.initials: RK
authors.lastname: Jain
authors.affiliation: Assistant Professor, Department of Orthodontics, The Tamilnadu Government Dental College and Hospitals , Chennai, India .
authors.forename: Sridhar Prem
authors.initials: SP
authors.lastname: Kumar
authors.affiliation: Professor, Department of Orthodontics, Balaji Dental College , Chennai, India .
authors.forename: W S
authors.initials: WS
authors.lastname: Manjula
keywords: Incisor intrusion; J-hook headgear; Mini implants; Utility arch