Comparative Evaluation of Platelet-Rich Fibrin (PRF) and Concentrated Growth Factor (CGF) as Carriers for Antibiotics—In Vitro Study

The rising prevalence of antibiotic resistance underscores the need for localized drug delivery systems that minimize systemic exposure. Autologous platelet concentrates (APCs), including concentrated platelet-rich fibrin (c-PRF) and liquid-phase concentrated growth factors (LPCGFs), have emerged as potential carriers for antimicrobial agents. This study aimed to evaluate the efficacy of c-PRF and LPCGF as carriers for three antibiotic formulations-amoxicillin with clavulanic acid, clindamycin, and a combination of amoxicillin with metronidazole-against methicillin-sensitive <i>Staphylococcus aureus</i> (MSSA), methicillin-resistant <i>Staphylococcus aureus</i> (MRSA), and <i>Enterococcus faecalis</i> (low-level natural resistance). The disk diffusion method was employed to incorporate antibiotics into both APC types, which were then applied to disks placed on bacterial cultures. The size of the inhibition zones was measured at 20-, 40-, 60-, and 80-h intervals. Every 20 h, the disks were transferred to a new Petri dish. Statistical analysis included Welch's <i>t</i>-test and two-way ANOVA. c-PRF demonstrated superior performance as a carrier for amoxicillin and clindamycin, showing the presence of inhibition zones for up to 60 h. In contrast, LPCGF exhibited greater efficacy when used with the amoxicillin-metronidazole combination, particularly at higher concentrations. Both APCs showed limited effectiveness against <i>E. faecalis</i> when combined with clindamycin. The study confirms the suitability of autologous platelet concentrates as localized antibiotic delivery systems. The choice between c-PRF and LPCGF should be guided by the drug's physicochemical properties and clinical application. APCs offer a promising alternative for targeted antimicrobial therapy in dental and surgical settings.