The Effectiveness of Clear Aligner and Traditional Fixed Appliances in Achieving Good Occlusion in Complex Orthodontic Cases

Study Overview
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Brief Summary
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Patients who have severe crowding that requires four premolars extraction will be treated in this study. The efficacy and effectiveness of in-house clear aligners therapy compared with vestibular fixed appliances in the treatment of severe crowding malocclusion cases requiring the extraction of first premolars will be evaluated using Little's irregularity index (LII), Peer assessment rating index (PAR), and treatment duration. There are two groups: First group (Experimental): the patients in this group will be treated using clear aligners. Second group (Control): the patients in this group will be treated using fixed appliances.

Detailed Description
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For years, orthodontists and dentists have used removable appliances for orthodontic treatment. With the CAD/CAM technology, clear aligners treat a broader range of cases with greater precision. They consist of a series of plastic aligners that are intended to replace conventional wire and bracket technology for many orthodontic cases. Each custom-manufactured aligner exerts gentle, continuous forces to move teeth incrementally from their original state to a final, treated state. Each aligner is worn for about two weeks, then replaced by the next in the series until the final position is achieved.

Official Title
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Evaluation of the Achieved Occlusal Relationships Using the PAR Index Between the In-house Constructed Clear Aligners and Fixed Appliances in Patients With Extraction-based Treatment Plans: A Randomized Control Clinical Trial

Conditions
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Crowding, Tooth

Intervention / Treatment
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* Device: Clear aligners
* Device: Fixed appliances


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Class I skeletal and dental malocclusion severe crowding (more than 6 mm of tooth size-arch length discrepancy) Good oral hygiene and periodontal health. No congenitally missing or extracted teeth (except for the third molars). No history of previous trauma to the maxillofacial region or surgical interventions. Exclusion Criteria: Subject with psychological abnormalities. Subject with systemic diseases. Previous orthodontic treatment. Subject has known allergy to latex and plastic

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 25 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: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Clear aligners<br>The patients in this group will be treated using clear aligners. | Device: Clear aligners<br>* Each aligner will be worn for about two weeks, and then replaced by the next in the series until the final position is achieved.<br>|
| Active Comparator: Fixed appliances.<br>The patients in this group will be treated using fixed appliances. | Device: Fixed appliances<br>* Conventional wires and brackets will be used.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in PAR index | The PAR index will be used to provide objective assessment of treatment success. Each set of dental models prepared before and after treatment for each case will be occluded in maximum intercuspation and a calibrated PAR ruler is used to assign a value to each of the PAR index components: contact displacement in the upper and lower labial segment (UAS), overjet (OJ), overbite (OB), medline deviation (MID) and right and left buccazzzl occlusion (RBO, LBO). The score of each component is summed up to a total PAR score. A reduction in the PAR score of at least 30% classifies the case as 'improved'. A reduction of 22 points or more in the weighted PAR score classifies the case as 'greatly improved'. Improvements smaller than 30% are declared as 'worse or no different' | T0: one day before the commencement of treatment. T1: one day following the end of treatment | 
| Changes in Little's irregularity index | The Little's index measures the linear displacements in the horizontal plane between the contact points of the anterior teeth from the mesial surface of one canine to the contralateral one. The LII score is the sum of these linear measurements, and a higher score value indicates more severe irregularities of the anterior teeth | T0: one day before the commencement of treatment. T1: one day following the end of treatment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Treatment time | The treatment duration was calculated by months and will be compared between the groups | T1: one day following the end of treatment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Clear aligners, PAR index, Vestibular fixed appliances, Orthodontics, Crowding, Treatment duration