Effect of injectable platelet-rich fibrin on orthodontically induced root resorption during tooth movement: a biomarker-based randomized controlled trial.

OBJECTIVES: Orthodontically induced root resorption (OIRR) is a common adverse effect of orthodontic treatment, and early detection remains challenging. This randomized controlled trial aimed to evaluate the biological effect of injectable platelet-rich fibrin (i-PRF) on OIRR using dentin sialophosphoprotein (DSPP) levels in gingival crevicular fluid (GCF) as a biomarker during orthodontic tooth movement. MATERIALS AND METHODS: Thirty patients requiring bilateral maxillary first premolar extraction were randomly allocated to an i-PRF group (n = 15) or a control group (n = 15). In the intervention group, i-PRF was administered submucosally before incisor alignment. GCF samples were collected from maxillary central and lateral incisors at baseline (T0) and monthly for six months (T1-T6). DSPP concentrations were quantified using an enzyme-linked immunosorbent assay. Longitudinal changes in DSPP levels were analyzed using linear mixed-effects models to account for repeated measurements. RESULTS: DSPP levels showed a significant time-dependent increase in both groups for central and lateral incisors (p < 0.001). However, the pattern of DSPP release differed significantly between groups. From the fourth month onward, DSPP levels were significantly lower in the i-PRF group compared with controls (p < 0.05). Lateral incisors consistently exhibited higher DSPP concentrations than central incisors. CONCLUSIONS: Administration of i-PRF before incisor alignment was associated with lower DSPP expression during orthodontic tooth movement, suggesting a possible biological effect of i-PRF on OIRR. CLINICAL RELEVANCE: The study provides preliminary biological evidence that i-PRF may influence processes associated with OIRR. If confirmed by future studies, i-PRF could serve as a minimally invasive adjunct to help reduce the risk of root resorption during orthodontic treatment. TRIAL REGISTRATION NO: CTRI/2023/08/056931 (Clinical Trial Registry of India).