Chesterfield Micro-implant Study Involving Three Types of Anchorage Methods in Orthodontics
Condition: Malocclusion; Class II Buccal Segment Relationship
MeSH terms: Malocclusion
Study type: Interventional

Summary: 
      Research problem:

      Anchorage reinforcement is effective with headgear provided patient compliance is optimal.
      Nance palatal arch have also been shown to be effective. Microscrews despite their popularity
      however have no scientific evidence to support their use.

      Aim:

      To compare the effectiveness of 3 methods of anchorage reinforcement 1) headgear 2) Nance
      palatal arch 3) orthodontic micro-screws.

      Hypothesis:

      There is no difference in the amount of anchorage loss between the three methods of anchorage
      reinforcement.

      Design:

      Randomized clinical trial.

      Setting: District General Hospital orthodontic department

      Participants: 78 patients requiring "absolute anchorage".

      Interventions: The subjects will be randomized into 3 groups. In group 1 headgear will be
      requested 12-14 hours per day. In group 2 a nance palatal arch will be placed for use as
      intra oral anchorage reinforcement. In group 3, orthodontic micro-screws will be used for
      anchorage.

      Method of investigation:

      The study will be of 78 'absolute anchorage' patients older than 12 years randomly assigned
      to one of three groups of anchorage reinforcement

      Outcome measures:

        1. Anchorage loss measured from lateral Cephalometric radiographs and 3-D model scanning,
           records will be taken at three points

        2. Patient perception of the different treatment methods, including surgical experience

      Data analysis: The data will be analysed on an intention to treat basis. Basic descriptive
      statistics and uni-variate tests will initially be done to explore the data. Final data
      analysis will involve the relevant multi-variate statistical modeling.

      Dissemination: Conference proceedings, journal papers and the Cochrane oral health group.
    

Detailed description: 
      Research problem:

      Anchorage reinforcement is effective with headgear provided patient compliance is optimal.
      Nance palatal arch have also been shown to be effective. Microscrews despite their popularity
      however have no scientific evidence to support their use.

      Aim:

      To compare the effectiveness of 3 methods of anchorage reinforcement 1) headgear 2) Nance
      palatal arch 3) orthodontic micro-screws.

      Hypothesis:

      There is no difference in the amount of anchorage loss between the three methods of anchorage
      reinforcement.

      Design:

      Randomized clinical trial.

      Setting: District General Hospital orthodontic department

      Participants: 78 patients requiring "absolute anchorage".

      Interventions: The subjects will be randomized into 3 groups. In group 1 headgear will be
      requested 12-14 hours per day. In group 2 a nance palatal arch will be placed for use as
      intra oral anchorage reinforcement. In group 3, orthodontic micro-screws will be used for
      anchorage.

      Method of investigation:

      The study will be of 78 'absolute anchorage' patients older than 12 years randomly assigned
      to one of three groups of anchorage reinforcement

      Data analysis: The data will be analysed on an intention to treat basis. Basic descriptive
      statistics and uni-variate tests will initially be done to explore the data. Final data
      analysis will involve the relevant multi-variate statistical modeling.

      I took professional statistical advice from a senior statistician at the University of
      Manchester. Analysis of covariance was used and Headgear (as our default treatment) was used
      as the reference category. Results with Nance and TADs are relative to the reference category
      of headgear.
    

Intervention name(s): Extraoral anchorage; Miniscrews; Nance
Intervention type(s): Device; Device; Device
Intervention description(s): Extra oral anchorage; Intraoral skeletal anchorage using mini screws; Intraoral dental anchorage by using Nance palatal arch on molars
Other intervention name(s): miniscrew for anchorage reinforcement; Nance button
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Investigator)
Primary purpose: Treatment
Keywords: Extractions; Anchorage supplementation