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RecruitingNCT03286569Updated Jan 7, 2026

Study the Effect of Upper Expansion Appliances on Lower Jaw Forward Projection/Growth

An interventional study of Upper arch Wilson quadhelex appliance in Overbite (Excessive) Horizontal, sponsored by University of Alberta. Recruiting at 1 site in Canada. Open to participants aged 9 Years to 11 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-01-07.

Sponsored by University of Alberta · Not applicable, Interventional, and Treatment

Phase
Not applicable
Study type
Interventional
Enrollment
60
Allocation
Randomized
Ages
9 Years to 11 Years
Sex
All
01

Study summary

Young children with backward positioned lower jaw/chin will be recruited to have an upper jaw expansion appliance. Previous research showed that the use of similar appliances can lead to lower jaw forward growth. 60 young children aged 9-11 will be recruited to have either active or non-active Wilson type upper arch expansion appliance. Patients will have special x-ray (Cone Beam computed tomography) before and after treatment (after 9 months) of starting the treatment. After participation, routine orthodontic treatment will be continued.

Read the detailed description

Previous research showed that the use of upper jaw expansion appliances can lead to lower jaw forward growth (1). 60 young children aged 9-11 with backward positioned lower jaw/chin will be recruited to have either active or non-active Wilson type upper arch expansion appliance. Patients will have special x-ray (Cone Beam computed tomography) before and after treatment (after 9 months) of starting the treatment. After participation, routine orthodontic treatment will be continued.

02

Conditions studied

  • Overbite (Excessive) Horizontal

Browse trials for

03

Who can participate

Ages eligible
9 Years to 11 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Inclusion criteria

  1. Class II skeletal due to lower jaw backward projection
  2. Class II malocclusion
  3. Early mixed dentition (all first permanent molars erupted, as well as all erupting upper and lower permanent incisors)

Exclusion criteria

Exclusion Criteria:

  1. Other orthodontic treatment provided
  2. Growth problems (craniofacial syndromes, etc.)
04

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Single group
Masking
Double (Participant, Outcomes assessor)
Enrollment
60 participants (estimated)

Study arms

  • Active comparator
    Active upper Wilson appliance

    Active upper arch Wilson quadhelex appliance

    Device: Upper arch Wilson quadhelex appliance

  • Placebo comparator
    Non active upper expansion appliance

    Non-Active upper arch Wilson quadhelex appliance

    Device: Upper arch Wilson quadhelex appliance

Interventions

  • DeviceUpper arch Wilson quadhelex appliance

    Upper arch Wilson quadhelex appliance

05

What researchers measure

Primary outcomes

  1. Lower jaw size

    Lower jaw size will be evaluated by computed tomography.

    Time frame: 9 months

  2. Lower jaw projection

    Lower jaw projection will be evaluated by computed tomography.

    Time frame: 9 months

Secondary outcomes

  1. Jaw joint size

    Jaw joint size will be evaluated by CBCT

    Time frame: 9 months

  2. Base of skull bone size

    Base of skull bone size will be evaluated by CBCT

    Time frame: 9 months

  3. Base of skull bone position

    Base of skull bone positions will be evaluated by CBCT

    Time frame: 9 months

  4. Jaw joint position

    Jaw joint will be evaluated by CBCT

    Time frame: 9 months

06

Study locations

1 of 1 sites recruiting
  • University of Alberta
    Edmonton, Alberta T6G 2R3, Canada
    Recruiting
07

References and documents

Publications

  • McNamara JA Jr, Sigler LM, Franchi L, Guest SS, Baccetti T. Changes in occlusal relationships in mixed dentition patients treated with rapid maxillary expansion. A prospective clinical study. Angle Orthod. 2010 Mar;80(2):230-8. doi: 10.2319/040309-192.1. PubMed 19905846 ↗
  • Guest SS, McNamara JA Jr, Baccetti T, Franchi L. Improving Class II malocclusion as a side-effect of rapid maxillary expansion: a prospective clinical study. Am J Orthod Dentofacial Orthop. 2010 Nov;138(5):582-91. doi: 10.1016/j.ajodo.2008.12.026. PubMed 21055598 ↗
08

Registry details

Key details

Study ID
NCT03286569
Lead sponsor
University of Alberta
Responsible party
Sponsor
First posted
Sep 18, 2017
Start date
Apr 1, 2019
Primary completion
Feb 1, 2027 (estimated)
Completion
Feb 1, 2027 (estimated)
Last update
Jan 7, 2026

Study contacts

Dr. Tarek El-Bialy, PhD
Contact
telbialy@ualberta.ca
780-492-2751
Rabia Njie, BDS
Contact
rnjie@ualberta.ca
780-850-8752

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
Yes
View the source record on ClinicalTrials.gov ↗

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