The Use of a Modified Dentoalveolar Distractor to Retract Maxillary Canines

Study Overview
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Brief Summary
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In this study, two distractors will be used to retract maxillary canines into the extraction sites. The first distractor is a modified Hyrax expander with two arms soldered to two bands connected to a canine and a molar; and the second one is a similar to the first one but with the addition of a third arm. The purpose of this investigation is to compare the two distractors in terms of: final position of the canine, canine pulp vitality, molars' anchorage, patient's acceptance to the appliance.

Detailed Description
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The retraction of the canines is one of the longest and most important stages in the orthodontic treatment of cases that require premolars extraction. The retraction phase of the canines into an extraction site with conventional treatment method usually lasts about 4 to 6 months under normal circumstances. The use of dentoalveolar distraction (DAD) technique has been considered a very important step in this field. It has been shown by early case reports that this technique can be employed to retract canines within 10 to 14 days. Although DAD is thought to accelerate tooth movement during canine retraction, a significant amount of tipping (distal tilting) was observed in many case reports. So in this study, there is an intention to apply a modified DAD device on one side of the mouth and to compare it with the conventional one applied on the opposite side of the mouth in each participating patient.

Official Title
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A Comparison Of The Short-Term Therapeutic Effects Between Two Distractors Used For The Retraction Of Maxillary Canines By Dentoalveolar Distraction Osteogenesis

Conditions
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Orthodontic Patients Requiring Canine Retraction

Intervention / Treatment
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* Device: modified dentoalveolar distractor


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Indication for extraction of upper first premolar and conducting canine retraction Good oral hygiene Exclusion Criteria: Buccal or palatal inclination of the canines Mesial or distal inclination of the canines Contraindication to minor surgery Previous orthodontic or surgical treatment Root canal treatment to the canines Malformation of the canines

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: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: modified dentoalveolar distractor<br>Canine retraction will be accomplished using a modified dentoalveolar distractor | Device: modified dentoalveolar distractor<br>* Here, the modified distractor is going to be used when retracting the canine.<br>|
| No Intervention: conventional dentoalveolar distractor<br>Canine retraction will be accomplished using a conventional dentoalveolar distractor | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in the mesiodistal inclination of the canine | This will be measured using a lateral cephalogram taken at these assessment times. The long axis of the canine will be drawn on the tracing of the cephalogram at each assessment time and this long axis will be measured with reference to anterior cranial base. | This will be measured at three times: T0, one day before installing the distractor; T1, in the same day of finishing the retraction phase; T2, in the same day of device removal from the mouth. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Canine Pulp Vitality | This variable is going to be measured clinically | This will be measured at three times: T0, one day before installing the distractor; T1, in the same day of finishing the retraction phase; T2, in the same day of device removal from the mouth. | 
| Molars Anchorage Loss | This will be measured using cephalograms and study models | Upper first molar position will be measured at three assessment times: T0, one day before installing the distractor; T1, in the same day of finishing the retraction phase; T2, in the same day of device removal from the mouth. | 
| Patient acceptance to each distractor | Using a visual analog scale. | This is going to be measured at: (T1) first day following surgery, (T2) five days following surgery, (T3) two weeks following surgery, and (T4) at the time of appliance removal. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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canine retraction, acceleration of tooth movement, dentoalveolar distraction osteogenesis