The Buffy Coat Platelet-Rich Fibrin Concentrate On Chelated Root Dentin. An In-Vitro Model In Regenerative Endodontics.

Aim To characterize, using scanning electron microscopy (SEM), the morphology and structural conformation of the buffy coat – platelet-rich fibrin concentrate on root dentin conditioned with different chelation schemes.
Materials and methods An in vitro study was conducted on 35 human hemi-sected roots, randomly assigned to 7 groups. The samples were immersed in different solutions as follows: G1 – distilled water (DW), G2 – 17% EDTA + DW, G3 – 17% EDTA, G4 – chitosan (Cs) + DW, G5 – Cs, G6 – nanoparticulate chitosan (Csnp) + DW, G7 – Csnp.  A sample of human blood was collected by venipuncture, then centrifuged to obtain a PRF matrix from which the buffy coat was extracted and placed on dentin surfaces for SEM analysis. A comparison of BEAI across groups was performed using the nonparametric Kruskal-Wallis test. As a complement, a multiple comparison with the Dunn test (with Benjamini-Hochberg correction).
Results Significant differences were observed among groups (p = 0.011). Chitosan without a final rinse yielded a dense, well-organized fibrin network firmly adhered to dentin, with proper cellular integration, whereas EDTA showed limited interaction with the scaffold. 
Conclusions The chelating agent and final rinse protocol significantly influence the initial stability of the buffy coat as a scaffold. Chitosan demonstrated superior performance compared to EDTA in regenerative endodontic applications.
Clinical Relevance An approach to regenerative treatments is to examine the role of chelation in dentin, which supports the stability of a solid matrix, such as the buffy coat, which contains bioactive factors and cellular elements essential for regeneration.

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