The Effect of Platelet-rich Plasma on the Rate and Type of Orthodontic Tooth Movement
Condition: Class II Division 1 Malocclusion
MeSH terms: Malocclusion
Study type: Interventional

Summary: 
      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: 
      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.
    

Intervention name(s): PRP injection; En-masse retraction of upper anterior teeth
Intervention type(s): Biological; Procedure
Intervention description(s): 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.; 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.
Other intervention name(s): platelet-rich plasma (PRP)
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment