Clinical Study on the Dose-Dependent Effects of Submucosal Platelet Rich Plasma Injection and Accelerating Orthodontic Tooth Movement

We have demonstrated experimentally and clinically that injection of platelet rich plasma (PRP) during orthodontic tooth movement accelerates rate of tooth movement through increase of osteoclastic activity and decrease of bone density. However, the dose-dependent effects between the PRP platelet & WBC count and acceleration of tooth movement, and the affects by the baseline alveolar bone density and metabolism have not been well explored clinically. This is a 3-year prospective clinical project. The aims are to (1) study the possible linear dose-dependent effects between the PRP platelet & WBC count and acceleration of tooth movement, and the affects by the baseline alveolar bone density and metabolism so that clinical parameters could be setup for customized PRP injection, and to (2) investigate the change of alveolar bone density and metabolism after PRP injection. Study design & methods: Seventy adult patients who have maxillary and mandibular anterior crowding will be included in 3 years, including fifty patients receiving only once submucosal PRP injection at the beginning of orthodontic treatment (experimental-group), and another 20 patients receiving no PRP injection (control-group). For the experimental-group, CBC, platelet & WBC count in PRP, serum alkaline phosphatase (ALP) and type I collagen of C-terminal telopeptide (ICTP) will be analyzed during autogolous PRP preparation. Both for the experimental and control groups, non-invasive records will be taken at the beginning and in the 1st, 2nd, 3rd, & 4th month after commencing orthodontic treatment (except dental CT scan). The dental casts will be analyzed for the velocity changes of the tooth movement (average Irregularity Index change per month), dental CT scan for the alveolar bone density (at the beginning and in the 1st, 2nd, & 4th month), Periotest for the tooth mobility, and gingival crevicular fluid (GCF) samples for the analyses of bone specific alkaline phosphatase and ICTP by ELISA. The data will be analyzed for the possible dose-dependent effect between rate of tooth movement and platelet & WBC count in PRP, the intra- and inter-group differences in the changes of alveolar bone density and metabolism, and will be crossly examined for the possible correlations and interactions. Expecting results: (1) The platelet & WBC count in PRP has a positive dose-dependent effect on the rate of orthodontic tooth movement, and the alveolar bone metabolism is a positive factor but the alveolar bone density is a negative factor in accelerating tooth movement. (2) The alveolar bone density decreases after the PRP injection and then resumes gradually. The alveolar bone metabolism increases after the PRP injection and then resume gradually.

Project ID:PC10008-0718
External Project ID:NSC100-2314-B182-058