The Efficacy of Tow Mechanics for Total-maxillary-arch-distalization
Condition: Malocclusion; Class II Division 1 Malocclusion
MeSH terms: Malocclusion; Malocclusion, Angle Class II
Study type: Interventional

Summary: 
      Patients with class II division 1 malocclusion who have increased overjet will be treated in
      this study. The efficacy of one-jaw and tow-jaw mechanics for mini-implants anchored
      total-maxillary-arch-distalization in the treatment of class II division 1 malocclusion will
      be assessed. The skeletal, dental and soft tissues changes resulted by these tow
      interventions will be studied. As well as, the pain levels, oral-health related quality of
      life during all stages of the treatment and the smile components will be explored and
      compared with the traditional treatment results of this type of malocclusion (en-mass
      retraction with first premolars extraction).

      There are three groups :

        1. a group of patients in which participants will be undergo to the one-jaw mechanic for
           mini-implants anchored total-maxillary-arch-distalization (mini-implants in the
           maxillary arch).

        2. a group of patients in which participants will be undergo to the tow-jaw mechanic for
           mini-implants anchored total-maxillary-arch-distalization (mini-implants in the
           mandibular arch with class II elastics).

        3. a group of patients in which participants will be undergo to the en-mass retraction with
           first premolars extraction with mini-implants in the maxillary arch.
    

Detailed description: 
      The number of adults seeking active orthodontic treatment has been increasing over the past
      several decades. Older patients tend to show a greater demand for esthetic considerations
      during and after active treatment. Also, the preservation of existing dentoalveolar
      structures becomes a more critical issue in their treatment, and this mandates vigilant
      monitoring of the periodontal and occlusal statuses throughout the course of tooth movement.

      Nowadays, the tendency towards choosing nonextraction approaches has been increasing because
      of the availability of effective and minimally invasive treatment modalities. Several
      strategies have been introduced to address the arch length discrepancy by gaining space
      through enamel stripping, arch expansion, and distalization of dentition. Moreover, the
      introduction of temporary anchorage devices (TADs) has enhanced the efficiency of
      nonextraction therapies via improved anchorage management.

      The total-maxillary-arch-distalization is a treatment modality respect the principle of
      structures preservation and the esthetic demands of patients.

      Most of the published literature were case reports or retrospective studies so, there is a
      high need for a randomized controlled trial to assess some of these suggested approaches.

      The current study will have three parallel arms as following:

        1. Group 1: a group of patients in which participants will be undergo to the one-jaw
           mechanic for mini-implants anchored total-maxillary-arch-distalization (the
           mini-implants will be inserted in the maxillary arch between the roots of 2nd premolar
           and 1st molar and closer to the molar, then a force of 250 g will be applied from the
           TAD to a hook lateral to the laterals).

        2. a group of patients in which participants will be undergo to the tow-jaw mechanic for
           mini-implants anchored total-maxillary-arch-distalization (the mini-implants will be
           inserted in the mandibular arch between the 2nd premolar and 1st molar, then, a class II
           elastics 3/16 and 6.5oz will be use from the TAD to the hook of canines brackets).

        3. a group of patients in which participants will be undergo to the en-mass retraction with
           first premolars extraction with mini-implants in the maxillary arch inserted between the
           2nd premolar and 1st molar, then a force of 250 g will be applied from the TAD to a hook
           lateral to the laterals .

      Prior to enrollment of each subject into the study, they will be examined completely to
      determine the orthodontic treatment plan. The operator will inform them about the aim of the
      study and ask them to provide a written informed consent.

      A fixed orthodontic appliance will be bonded ( MBT 0.022 inch prescription), the active
      distalization or retraction will start when the rectangular stainless steel archwires (0.019"
      × 0.025").

      The end of the treatment will be determined clinically when a class I canine relationship
      achieved with a good incisor relationship obtained.

      Dental casts will be used for the quantification of the anteroposterior movement of the
      anterior teeth and the first molars before the beginning of the treatment and when a class I
      canine relationship achieved with a good incisor relationship obtained.

      Cephalograms will be taken 3 times: the first before the beginning treatment for diagnosis
      purpose, the second: after the completion of leveling and alignment stage, the third: when a
      class I canine relationship achieved with a good incisor relationship obtained.

      Smile photographs will be taken in 2 times: the first before the beginning of the treatment,
      the second: after the treatment
    

Intervention name(s): One-jaw mechanic total maxillary arch distalization; Two-jaw mechanic total maxillary arch distalization; en-mass retraction
Intervention type(s): Other; Other; Other
Intervention description(s): A group of patients in which participants will be undergo to the one-jaw mechanic for mini-implants anchored total-maxillary-arch-distalization (the mini-implants will be inserted in the maxillary arch between the roots of 2nd premolar and 1st molar and closer to the molar, then a force of 250 g will be applied from the TAD to a hook lateral to the laterals).; A group of patients in which participants will be undergo to the tow-jaw mechanic for mini-implants anchored total-maxillary-arch-distalization (the mini-implants will be inserted in the mandibular arch between the 2nd premolar and 1st molar, then, a class II elastics 3/16 and 6.5oz will be use from the TAD to the hook of canines brackets).; A group of patients in which participants will be undergo to the en-mass retraction with first premolars extraction with mini-implants in the maxillary arch inserted between the 2nd premolar and 1st molar, then a force of 250 g will be applied from the TAD to a hook lateral to the laterals .
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment