Effect of Bilateral Distalization of Upper First Molars in a Group of Patients After Extraction of Maxillary Second Molars

Study Overview
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Brief Summary
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There is a scarcity in the current literature regarding such appliance and its effect on distalizing the first maxillary molar in absence of the second molar. Therefore, this study was made to evaluate the effect of bilateral distalization of upper first molars in a group of patients after extraction of maxillary second Molars using infra zygomatic mini implants.

Detailed Description
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The appliances available for distalization used to be mainly extraoral distalizing appliances which depended entirely on patient cooperation and compliance. Even after the emergence of intra-oral distalizing appliances they had adverse dentoalveolar effect such as anchorage loss and flaring of the upper anterior teeth. Thus, this study was made in order to evaluate the efficiency of our proposed appliance in the treatment of Class II patients while avoiding the adverse effects mentioned above.

Official Title
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Effect of Bilateral Distalization of Upper First Molars in a Group of Patients After Extraction of Maxillary Second Molars Using Infra Zygomatic Mini Implants: A Prospective Clinical Trial

Conditions
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Class II Malocclusion

Intervention / Treatment
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* Device: Intra-Oral Distalizing Device


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Female Patients with cervical vertebra maturation index (CVMI) 5 & 6. From quarter unit to 3\4-unit class II molar relationship. An overjet of an average 6mm. Full Set of permanent dentition except for the maxillary second molar. Favorable path of eruption for the maxillary third molar. Exclusion Criteria: Medically compromised Patients. Patients under long term medications. Patients having sever periodontal disease. CVMI 3 or less Full unit class II cases

Ages Eligible for Study
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Minimum Age: 16 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intra-oral Distalizing Appliance<br>Two infra zygomatic mini-implants will be placed Bands will be cemented to upper first molars. The inner bow (1.2mm) is a modified version of the inner part of a conventional face bow. Two hooks were soldered onto the inner bow distal to the lateral incisor teeth regions, and U loop at 1st premolar region, and bends acting as mesial stop will be bent in front of the maxillary first molars. Orthodontic force 300 mg per side Will be delivered by Niti closed coil spring which is attached from infra zygomatic mini screw to the hook soldered to the wire framework. | Device: Intra-Oral Distalizing Device<br>* The inner bow (1.2mm) is a modified version of the inner part of a conventional face bow. Two hooks were soldered onto the inner bow distal to the lateral incisor teeth regions, and U loop at 1st premolar region, and bends acting as mesial stop will be bent in front of the maxillary first molars. The anterior component of the inner bow is 3 mm free from the labial surface of anterior teeth<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| linear distalization of maxillary 1st molar. | Efficiency of the proposed appliance to induce distalization of the upper 1st molar measured on Scanned dental casts as well as cone-beam computed tomography (CBCT) in millimetres. | Up until Class I Molar Relation (a maximum of 8 months regardless) | 
| Rate of maxillary 1st molar Distalization in mm/ month. | Efficiency of the proposed appliance to induce distalization of the upper 1st molar measured on Scanned dental casts with a monthly follow up in millimetres. | Up until Class I Molar Relation (a maximum of 8 months regardless) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in Intermolar width in mm. | Effect of the proposed appliance on the transverse Dental changes in the upper buccal segment through scanned dental cast in millimetres | Up until Class I Molar Relation (a maximum of 8 months regardless) | 
| Changes of Molar inclination in degrees. | Effect of the proposed appliance on the angulation of the first permanent molar through scanned dental cast and cone-beam computed tomography (CBCT) in degrees. | Up until Class I Molar Relation (a maximum of 8 months regardless) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Intermolar Width, Molar Inclination, Intra-oral Appliance, Infrazygomatic Mini-screws, Distalization