Treatment Adherence With Twin-Blocks for Correction of Class II Malocclusion

Study Overview
=================
Brief Summary
-----------------
To compare the effect of two control intervals (once every 4th week or once every 6th week) on the wear time of a Twin Block removable appliance.

Detailed Description
-----------------
If the patient fulfill the inclusion criteria, they will be asked to participate in the study. After being informed about the study and the planned treatment, participants and their guardians will give their written consent to participate in the study. Therafter they will be consecutively randomized into one of two groups with different control intervals, Group 1 (every 4th week) and Group 2 (every 6th week). They will recieve a clinical and radiological examination and then start treatment with a Twin Block appliance. The Twin Block appliance will be fitted with a digital timer module to measure the wear time of the appliance objectively.

Official Title
-----------------
Treatment Adherence With Twin-Blocks for Correction of Class II Malocclusion - a Randomized Controlled Trial on Two Check-up Prescriptions

Conditions
-----------------
Compliance, Patient, Treatment Adherence

Intervention / Treatment
-----------------
* Device: Twin block


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Healthy patients (ASA 1 and 2) Overjet of 6 mm or more Incomplete lip closure Exclusion Criteria: Severe chronic conditions such as asthma or allergies Neuroopsychiatric disorders Craniofacial syndromes Previous orthodontic treatment

Ages Eligible for Study
-----------------
Minimum Age: 8 Years
Maximum Age: 14 Years

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

Accepts Healthy Volunteers
-----------------
No

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

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Control group, controlled every 6th week<br>This group was controlled every 6th week, in accordance with what is deemed to be golden standard for treatment with a Twin Block orthodontic appliance. | Device: Twin block<br>* Twin Block orthodontic appliance for treating patients with Angle class II molar relationship and a large horizontal overjet, often in combination with an incomplete lip closure<br>|
| Experimental: Test group, controlled every 4th week<br>This group was controlled every 4th week, testing if a more frequent control interval would increase compliance with a Twin block orthodontic appliance. | Device: Twin block<br>* Twin Block orthodontic appliance for treating patients with Angle class II molar relationship and a large horizontal overjet, often in combination with an incomplete lip closure<br>|

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

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Wear time of the Twin Block appliance, compared between participants randomized into two groups with different check up intervals | To measure if the wear time of the Twin Block appliance would increase if the control interval increased from once every 6th week to once every 4th week. The wear time was registered using the TheraMon system, and was measured in hours per day. | From randomization to 12 months of treatment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in overjet, compared between participants randomized into two groups with different check up intervals | To see if change in overjet would differ between or within the groups before and after treatment was finished. Horizontal overjet was measured in millimetres on study casts before and after treatment was finished. | From randomization to treatment completion, up to 24 months. | 
| Change in overbite, compared between participants randomized into two groups with different check up intervals | To see if change in overbite would differ between or within the groups before and after treatment. Overbite was measured in millimetres on study casts taken before and after treatment. | From randomization to treatment completion, up to 24 months. | 
| Change in molar relationship, compared between participants randomized into two groups with different check up intervals | To see how molar relationship would be differ between or within the two groups before and after treatment, measured in Angle classification on study casts before and after treatment completion. | From randomization to treatment completion, up to 24 months. | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Orthodontic, Removable, Compliance, Adherence, Twin Block