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

Study Overview
=================
Brief 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.

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.

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

Conditions
-----------------
Overbite (Excessive) Horizontal

Intervention / Treatment
-----------------
* Device: Upper arch Wilson quadhelex appliance


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Class II skeletal due to lower jaw backward projection Class II malocclusion Early mixed dentition (all first permanent molars erupted, as well as all erupting upper and lower permanent incisors) Exclusion Criteria: Other orthodontic treatment provided Growth problems (craniofacial syndromes, etc.)

Ages Eligible for Study
-----------------
Minimum Age: 9 Years
Maximum Age: 11 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Active upper Wilson appliance<br>Active upper arch Wilson quadhelex appliance | Device: Upper arch Wilson quadhelex appliance<br>* Upper arch Wilson quadhelex appliance<br>|
| Placebo Comparator: Non active upper expansion appliance<br>Non-Active upper arch Wilson quadhelex appliance | Device: Upper arch Wilson quadhelex appliance<br>* Upper arch Wilson quadhelex appliance<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Lower jaw size | Lower jaw size will be evaluated by computed tomography. | 9 months | 
| Lower jaw projection | Lower jaw projection will be evaluated by computed tomography. | 9 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Jaw joint size | Jaw joint size will be evaluated by CBCT | 9 months | 
| Base of skull bone size | Base of skull bone size will be evaluated by CBCT | 9 months | 
| Base of skull bone position | Base of skull bone positions will be evaluated by CBCT | 9 months | 
| Jaw joint position | Jaw joint will be evaluated by CBCT | 9 months |