title: Co-axial computed tomography for optimizing orthodontic miniscrew implant size and site of placement.
abstract: OBJECTIVE
  Absolute anchorage has been a critical aspect in orthodontics. Quantity and quality is a critical factor MSI placement. The present study was designed using a spiral computed tomography to assess the bone availability and clinically assess the optimized position and site for MSI placement in the posterior region.
  
  
  METHODS
  Spiral computed tomography images often patients were obtained with requirement of MSI placement. Mesiodistal inter-radicular distance in the posterior region of the maxilla over narrowest inter-radicular space was measured at 2, 4, 6 and 8 mm from cementoenamel junction.
  
  
  RESULTS
  In the maxilla, the greatest inter-root distance was observed between the first molar and the second premolar at the 8-mm level from the CEJ. The inter-root distances at 4, 6, and 8 mm were significantly larger than the distance at 2 mm, showing a gradual increment as the level approaches the root apex.
  
  
  CONCLUSIONS
  The optimal site for placement of a frequently used MSI (diameter 1.8 to 2.0 mm) in between 2nd premolar--1st molar could be 4 mm from the CEJ and between 1st molar--2nd molar be 6 mm from the CEJ.
authors.affiliation: ITS Dental College, Hospital and Research Center, National Capital Region, Delhi, India.
authors.forename: Karan
authors.initials: K
authors.lastname: Bhalla
authors.forename: Anmol S
authors.initials: AS
authors.lastname: Kalha
mesh_terms: D000328:Adult; D001641:Bicuspid / Q000000981:diagnostic imaging; D001863:Bone Screws; D003724:Dental Arch / Q000000981:diagnostic imaging; D006801:Humans; D008334:Mandible / Q000000981:diagnostic imaging*; D008437:Maxilla / Q000000981:diagnostic imaging*; D008963:Molar / Q000000981:diagnostic imaging; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation / Q000379:methods*; D011446:Prospective Studies; D036542:Tomography, Spiral Computed / Q000379:methods*; D019227:Tooth Apex / Q000000981:diagnostic imaging; D019237:Tooth Cervix / Q000000981:diagnostic imaging; D014092:Tooth Root / Q000000981:diagnostic imaging