The Effect of Platelet-rich Plasma on the Rate and Type of Orthodontic Tooth Movement

Study Overview
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Brief Summary
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This study aims to assess the effect of PRP on the rate and type of OTM during en-masse frictionless retraction of maxillary anterior teeth using a segmental arch technique. Thirty adult patients exhibiting class II division 1 malocclusion requiring upper first premolar extractions followed by en-masse retraction will participate in the study. They will be randomly and equally distributed into the PRP group (G1) and the control group (G2). The injection of PRP will be performed pre-retraction. The rate of orthodontic tooth movement will be assessed clinically by measuring the extraction space with a digital caliper. The cephalometric radiographs will evaluate the type of OTM at the beginning of en-masse retraction (T0) and at the middle of en-masse retraction (T1).

Detailed Description
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One of the most important challenges in daily practice is prolonged orthodontic treatment duration. Many therapeutic procedures, such as chemical interventions, have been introduced to minimize orthodontic treatment time. Even though all the methods of chemically assisted acceleration of OTM increase the rate of bone turnover and increase the rate of tooth movement, however, these chemical agents, i.e., hormones or vitamin D3, have many problems such as systemic effects and short half-life which make them not practical in clinical orthodontic. Therefore, the injection of PRP has been proposed. -In both groups, two first upper premolars were extracted. In all patients, fixed metal orthodontic brackets with MBT prescription 0.022 were bonded. After the arches were leveled and aligned, a rigid sectional archwire (0.021 x 0.025 in stainless steel) was used for the anterior six teeth. To strengthen anchorage, microscrews (diameter 1.6 mm; length 10 mm) were inserted at 8mm from the archwire into the inter-radicular space between the maxillary first molar and second premolar. Two crimpable hooks were used with a height of 8 mm between the lateral incisor and canine on both sides of the sectional wire 0.021x0.025 to pass the force vector as close as possible to the center of resistance. En-masse retraction began one week after premolar extraction, using calibrated nickel-titanium coil springs with 175 g force per side. -In PRP, 48 ml of blood was collected from the patient in sterile tubes with ACD-A as an anticoagulant. PRP was prepared as follows: Initially, the blood was centrifuged at 2000 rpm for 6 minutes. After separation of the blood, PRP and some Platelet-Poor Plasma (PPP) were collected and mixed in a dry tube, and then a second centrifugation was done at 2700 rpm for 3 minutes. After the second centrifugation, the lower 1/3rd of the tube is PRP. About 4 ml of PRP was collected from the tube, and then the patient was injected with it. After regional anesthesia for pain control, 0.5 ml of PRP was slowly injected submucosally palatal to each tooth from the right canine to the left canine using a 1cc syringe. Paracetamol was described for the patient to control pain and ensure confirming not to use ibuprofen or another NSAIDS. The injection was applied one time.

Official Title
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Evaluation of the Rate and Type of Orthodontic Tooth Movement When Injecting Platelet-rich Plasma During Mini-implant-based Segmented En-masse Retraction of Upper Anterior Teeth: A Randomized Controlled Clinical Trial

Conditions
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Class II Division 1 Malocclusion

Intervention / Treatment
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* Biological: PRP injection
* Procedure: En-masse retraction of upper anterior teeth


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age range between 16 and 27 years Class II division I malocclusion in which extraction of upper first premolars is indicated skeletal class II relationships (4°<ANB<10°), Non-growing patients No maxillary constriction overjet >5 and <10 mm normal overbite of 0-50% normal anterior facial height No systemic disease. Exclusion Criteria: patients who have undergone previous orthodontic treatment patients who need orthopedic surgery moderate to severe anterior crowding (Disharmony Dento-Maxillary (DDM≥3) Poor oral hygiene, long-term use of medical drugs, especially NSAIDs

Ages Eligible for Study
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Minimum Age: 16 Years
Maximum Age: 27 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: PRP group<br>PRP will be injected in the palatal mucosa of the upper anterior teeth to accelerate orthodontic tooth movement. Patients in this group will undergo en-masse retraction of their upper front teeth using the same technique as the control group. | Biological: PRP injection<br>* The PRP will be prepared according to a well-established technique and then injected into the palatal mucosa of the upper anterior teeth before retraction.<br>* Other names: platelet-rich plasma (PRP);|
| Active Comparator: Traditional retraction group<br>In this group, patients will undergo en-masse retraction of their upper front teeth using a frictionless method by using coil springs attached between the anterior portion of the dental arch (which is an anterior segment only) to the miniscrews placed between the upper second premolars and the upper first molars. | Procedure: En-masse retraction of upper anterior teeth<br>* The anterior teeth will be moved backward in an en-masse retraction way using a frictionless method. The anterior teeth will be manipulated as one block. Coil springs will be stretched between the power arms (in the anterior area) to the miniscrews placed in the posterior area bilaterally.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of retraction | Assessment will be performed clinically by measuring the change in the extraction space. The amount of distance being retracted in millimeters will be divided by the duration of retraction in months to estimate the retraction rate. | At the middle of the retraction procedure (the middle of closing the extraction space); this assessment time is expected to occur within 2 to 3 months and 3 to 4 months after the onset of retraction in the experimental and control groups, respectively | 
| Change in incisors' positions | The position of the incisal edges of the upper incisors will be measured according to a reference plance. | First time point (T0): one day before the beginning of retraction. Second time point (T1): in the middle of extraction space closure (expected to be within 2-3 months in the exp. group and 3-4 months in the control group). | 
| Change in position of the root apex of the incisor vertically (UIA-v). | This variable represents the distance between the upper root apex and X reference plane (line drawn from ANS to PNS which is called the palatal plane SPP). Lateral cephalograms will be taken, and this variable will be measured in millimeters. | First time point (T0): one day before the beginning of retraction. Second time point (T1): in the middle of extraction space closure (expected to be within 2-3 months in the exp. group and 3-4 months in the control group). | 
| Change in position of the incisal edge of the incisor vertically (UIE-v). | This variable represents the distance between the upper incisal edge and X reference plane. Lateral cephalograms will be taken and this variable is going to be measured in millimeters. | First time point (T0): one day before the beginning of retraction. Second time point (T1): in the middle of extraction space closure (expected to be within 2-3 months in the exp. group and 3-4 months in the control group). | 
| Change in position of the root apex of the incisor horizontally (UIA-h) | This variable represents the distance between the upper root apex and Y reference plane (line perpendicular to SPP at lateral PT). Lateral cephalograms will be taken and this variable is going to be measured in millimeters. | First time point (T0): one day before the beginning of retraction. Second time point (T1): in the middle of extraction space closure (expected to be within 2-3 months in the exp. group and 3-4 months in the control group). | 
| Change in position of the incisal edge of the incisor horizontally (UIE-h) | This variable represents the distance between the upper incisal edge and Y reference line. Lateral cephalograms will be taken and this variable is going to be measured in millimeters. | First time point (T0): one day before the beginning of retraction. Second time point (T1): in the middle of extraction space closure (expected to be within 2-3 months in the exp. group and 3-4 months in the control group). | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in the UI/SPP angle | This angle represents the inclination of the upper incisors (UI) relative to the palatal plane (or spinal plane SPP) in the sagittal direction. Lateral cephalograms will be taken, and this angle will be measured in degrees. | First time point (T0): one day before the beginning of retraction. Second time point (T1): in the middle of extraction space closure (expected to be within 2-3 months in the exp. group and 3-4 months in the control group). | 
| Change in the SNA angle | This angle represents the position of the upper jaw in the cephalometric analysis in the anteroposterior direction. Lateral cephalograms will be taken, and this angle will be measured in degrees. | First time point (T0): one day before the beginning of retraction. Second time point (T1): in the middle of extraction space closure (expected to be within 2-3 months in the exp. group and 3-4 months in the control group). | 
| Change in the ANB angle | This angle represents the spatial relationship between the upper and lower jaws in the cephalometric analysis in the anteroposterior direction. Lateral cephalograms will be taken, and this angle will be measured in degrees. | First time point (T0): one day before the beginning of retraction. Second time point (T1): in the middle of extraction space closure (expected to be within 2-3 months in the exp. group and 3-4 months in the control group). | 
| Change in Overbite | This variable represents The vertical overlap of the maxillary incisors over the mandibular incisors, measured relative to the incisal edges. Lateral cephalograms will be taken, and this variable will be measured in millimeters. | First time point (T0): one day before the beginning of retraction. Second time point (T1): in the middle of extraction space closure (expected to be within 2-3 months in the exp. group and 3-4 months in the control group). |