Molar Intrusion Using High Pull Headgear

Study Overview
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Brief Summary
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This prospective clinical study will evaluate the effect of high pull headgear for molar intrusion, compared with the control group, in adolescent patients with open bite malocclusion. The study sample will consist of 24 patients with anterior open bite divided equally in two groups. The sample will be collected consecutively from patients attending the Orthodontic Department at Damascus university. A modified version of the OBA (Open Bite Appliance),introduced by Erverdi and Usumez, will be applied for all patients. High pull headgears will be used in the first group, while, in the second (control) group, Open Bite Appliances will be used only. The skeletal and dentoalveolar changes occurring after intrusion of posterior teeth will be assessed by using posteroanterior and lateral cephalometric radiographs; pre- and post- treatment changes for each group will be evaluated.

Detailed Description
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Open bite malocclusion is considered one of the most difficult malocclusion to correct in orthodontic treatment because it appears as a result of different etiological factors such as genetic, dental, skeletal, functional, soft tissue, and habits that play roles in its development. Different treatment modalities used for the treatment of an anterior open bite. Multiloop edgewise archwires, miniscrews, high-pull headgear, and bite blocks have been used for anterior open bite patients, most open bite patients characterized by increased facial height, class II skeletal pattern, and vertical excess in maxillary posterior teeth. Functional appliances, magnets, posterior bite blocks, and high pull headgear are used for posterior teeth intrusion. It is possible to generate intrusive force by using high pull headgear. Furthermore, direction of force can be changed according to the center of resistance of the dental units to achieve a better tooth movement control. The intrusion of posterior teeth will lead to decreased lower facial height by a counterclockwise rotation of the mandible; and improve class II skeletal relationship. This study was the first clinical trial, that compare the effect of high pull headgear for molar intrusion with the control group in adolescent patients.

Official Title
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Skeletal and Dentoalveolar Changes Following Posterior Teeth Intrusion With High Pull Headgear in The Treatment of Patients With Anterior Open Bite

Conditions
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Anterior Openbite

Intervention / Treatment
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* Device: high pull headgear + OBA
* Device: OBA (control group)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with skeletal open bite determined by an increased B angle (angle between maxillary plane and mandibular plane), sum of Bjork and the mandibular plane angle (angle between SN plane and mandibular plane). patients between 12 and 18 years old with permanent dentition stage. Negative over bite of more than a mm Class I and Class II skeletal anteroposterior relationship. Exclusion Criteria: Previous orthodontic treatment. Patients with syndromes, clefts, or craniofacial abnormalities. Class III skeletal anteroposterior relationship.

Ages Eligible for Study
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Minimum Age: 12 Years
Maximum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: high pull headgear + OBA<br>A modified version of the Open Bite Appliance (OBA),introduced by Erverdi and Usumez, will be applied with high pull headgear for Orthoclassic ®1300 NE Alpha Drive, McMinnville, OR 97128 USA 866.752.0065. | Device: high pull headgear + OBA<br>* a modified version of the OBA (Open Bite Appliance),introduced by Erverdi and Usumez, will be applied in compination with a high pull headgear.<br>|
| Experimental: OBA (control group)<br>A modified version of the Open Bite Appliance (OBA),introduced by Erverdi and Usumez, will be applied only. | Device: OBA (control group)<br>* A modified version of the OBA (Open Bite Appliance),introduced by Erverdi and Usumez, will be applied alone (Control group)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overbite | The distance between the incisal edges of the upper and lower incisors, measured in mm. | This variable will be evaluated twice; T0 before treatment, and T1 at the end of molar intrusion which will be abroximately after 7 months. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Molar intrusion | The vertical distance between upper molars and the true horizontal plane (measured in mm) | This variable will be evaluated twice; T0 before treatment, and T1 at the end of molar intrusion which will be approximately after 7 months | 
| Mandibular autorotation | This variable will be measured by superimposition of the anterior cranial base | This variable will be evaluated twice; T0 before treatment, and T1 at the end of molar intrusion which will be approximately after 7 months | 
| Anterior facial height | The distance between the point N and the point Me | This variable will be evaluated twice; T0 before treatment, and T1 at the end of molar intrusion which will be approximately after 7 months | 
| Change in the anteroposterior position of the point B | The horizontal distance between point B and the true vertical plane | This variable will be evaluated twice; T0 before treatment, and T1 at the end of molar intrusion which will be approximately after 7 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Skeletal openbite, Molar intrusion, high pull headgear