METHOD: This review followed the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Nine electronic databases were searched until January 2024 without restrictions, followed by a hand search of the reference lists. Controlled randomized split-mouth human studies assessing the effect of platelet-rich fibrin on the rate of orthodontic tooth movement were included. All relevant data from the included studies were extracted and pooled for qualitative and quantitative analysis. Risk-of-Bias was assessed using the Cochrane Risk of Bias tool. The certainty of the evidence was graded using the Grading of Recommendations, Assessment, Development, and Evaluation tool.

RESULTS: From 515 studies, eleven randomized clinical trials were included for qualitative analysis and nine for quantitative analysis. The certainty of the evidence for these studies was low to moderate. The overall risk of bias for most studies was of some concern. The pooled estimate of the data from ten studies has a mean revealed difference of 1.31 (0.13-2.48) at a 95 % confidence interval with significant heterogeneity.

CONCLUSIONS: This systematic review suggest that platelet-rich fibrin enhances the orthodontic tooth movement rate, but the evidence quality was moderate. Further, based on the currently available evidence, the effectiveness of platelet-rich fibrin on the acceleration of orthodontic tooth movement could not be fully established.

METHODS: Bone thickness of the IZC region of 50 young adults (25 males and 25 females) aged 18-30 years were evaluated using cone-beam computed tomography images. The infrazygomatic bone thickness along the distobuccal root of the permanent maxillary first molar was assessed at various insertion angles (40° to 75° i.r.t the maxillary occlusal plane) with an increment of 5°. Student's t-test was used to compare the IZC bone thickness and height at the orthodontic miniscrew insertion site for males and females on the right and left sides.

RESULTS: The bone thickness of the IZC region above the distobuccal root of the permanent maxillary first molar was estimated between 4.39±0.25 mm and 9.03±0.45 mm for insertion angles from 40° to 75° to the maxillary occlusal plane. The corresponding OMSI insertion heights were 17.71±0.61 mm to 13.69±0.75 mm, respectively, above the maxillary occlusal plane. There were statistically significant gender and side-wise variations in bone thickness at the IZC area and insertion height.