Efficacy of Biological Technique in Upper Canine Retraction and Levels of Discomfort
Condition: Malocclusion, Angle Class II, Division 1
MeSH terms: Malocclusion; Malocclusion, Angle Class II; Overbite
Study type: Interventional

Summary: 
      Twenty patients need therapeutic extraction of the maxillary first premolars with subsequent
      retraction of the maxillary canines, will be divided randomly into two groups, and will
      randomly assigned to one side of the maxillary arch at the first premolar region , and the
      other side served as the control. canine retraction will be initiated after completion of the
      leveling and alignment phase via closed nickel-titanium coil springs applying 150 g of force
      per side , soldered transpalatal arch will be used as an anchor unit.

      Pre- and post distalization dental casts will be evaluated to study rate of canine
      distalization, over a follow-up period until a Class I canine relationship will be achieved.
      The levels of Pain and discomfort will be monitored using a questionnaire with a VAS scale
      administered three times during the first day after prf injection.
    

Detailed description: 
      Reduced orthodontic treatment duration is important for care providers and orthodontic
      patients.it is also desirable that aesthetic concerns and time dependent adverse events such
      as discomfort, pain, external root resorption, suboptimal oral hygiene, white spot lesions
      and dental caries are held to the minimum. Although the surgical assisted accelerated
      orthodontic tooth movement (such as distraction of periodontal ligament, distraction of
      dentoalveolus, periodontally accelerated osteogenic orthodontics (PAOO),Corticision,
      orthognathic surgery, piezocision, piezopuncture and micro osteoperforation). It has been
      proved to be the most effective one currently, its disadvantages are: it is a bone surgery,
      and it causes loss of alveolar bone that undermines the periodontal support of the target
      teeth.

      Noninvasive and nonsurgical methods have always been preferred by both the clinicians and the
      patients. These techniques have ranged from application of biological molecules to innovative
      technologies such as resonance vibration, cyclic forces, light electrical currents, magnetic
      field forces, low-intensity laser irradiation and low-level light therapy. Endogenously
      produced biologicals have been tested based on their roles in the turnover of alveolar bone
      in response to orthodontic tooth movement as well as during wound healing.

      That's why the submucosal injection of platelet rich plasma (PRP) is a technique developed
      for accelerating orthodontic tooth movement by simulating the effects of bone insult without
      surgery and loss of alveolar bone, Some researchers found that prp injection created a
      regional acceleratory phenomenon-like effect which forms the basis of rapid tooth movement
      compared with conventional orthodontic treatment.

      From here it has been thought about using a method to eliminate the surgical techniques' side
      effects. It has been found that platelet rich fibrin (PRF) has the ability to enhance tissue
      regeneration, accelerate wound healing and inducing stem cells differentiation through its
      growth factors (GFs).

      PRF characteristics in comparison to platelet rich plasma PRP are:

        1. its preparation is completely natural and there is no need for thrombin addition so
           there isn't immune reaction

        2. it contains stem cells

        3. it requires one stage centrifugation

        4. PRF has been reported to gradually release autologous growth factors and expressed
           stronger and more durable effect on the cellular proliferation and differentiation than
           PRP in vitro This is the first study in the world that will use i-PRF with Orthodontic
           treatment, because of its benefits and easiness of using in dental clinic Study sample
           that consists of 20 patients, was calculated using (G-power sample size calculator),
           depending on the rate of canine retraction with a study power of 95%.

      Allocation of the sides of intervention (PRF injection) and control sides is made by computer
      program (Excel).

      After ensuring of the patients compliance with the terms and conditions of this study, the
      purpose and methods of the study will be explained to the patients using Information Sheet.
      In case of approval to participate, the patients asked to sign the Informed Consent.

      Extra & Intra-oral photographs, impressions and clinical examination will be made.

      Canine retraction will be initiated after completion of the leveling and alignment phase via
      closed nickel-titanium coil springs applying 150 g of force per side at the same time 20ml of
      patients' blood will be withdrawn and centrifuged (700 rpm within 3 minutes) to get 4ml
      i-PRF. PRF will be injected at the area of the extracted first premolar, The first point
      place is in the buccal interventional side (supra periosteal injection) and the second point
      place is in the palatal interventional side(sub periosteal injection). PRF will be injected
      twice at the beginning and at the middle of the canine retraction.

      All measures will be analyzed before and after canine retraction between two sides.

      A questionnaire will be given to the patients to study pain level accompanying PRF injection
      compared to the control side. Pain will be assessed using Visual Analogue Scale (VAS) 1 (No
      Pain) - 10 (Worst Pain).

      A questionnaire will be given to the patients to study their acceptance of new treatment
      approach with comprehensive orthodontic treatments.
    

Intervention name(s): i-PRF; canine retraction
Intervention type(s): Biological; Procedure
Intervention description(s): i-PRF (injectable platelet rich fibrin) assisted upper canine retraction; upper canine retraction will be performed in one side of patients with Class II Division 1 malocclusion patients requiring therapeutic extraction of the maxillary first premolars
Allocation: Randomized
Intervention model: Crossover Assignment
Intervention model description: Two Arms injectable platelet rich fibrin group: consisted of two subgroups
Experimental group : injectable platelet rich fibrin assisted upper canine retraction Control group: conventional upper canine retraction
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment
Keywords: i-PRF (injectable platelet rich fibrin); canine retraction; pain and discomfort