Bone regeneration after adjuvant therapies for medication-related osteonecrosis of the jaws (MRONJ): a pre-clinical study

This study aimed to compare the bone response of medication-related osteonecrosis of the jaw (MRONJ) treated with bone debridement associated with photobiomodulation (PBM), antimicrobial photodynamic therapy (aPDT) or platelet-rich fibrin (PRF).

MRONJ was induced in 30 Wistar rats using zoledronate (0.06 mg/kg) followed by tooth extraction 21 days later. The experimental groups were no treatment (negative control), isolated debridement (positive control), or associated with aPDT, PBM, or PRF. Seven and 28 days after treatment morphometric analysis in microcomputed tomography images was performed. Data were statistically analyzed by two-way ANOVA (p ≤ 0.05).

In the negative control, the MRONJ progressed, showing a significant decrease in bone volume (BV; p = 0.04). The PBM and PRF had the highest BV at 28 days (p = 0.02). The trabeculae number at 7 days was significantly higher in PRF (p = 0.03) compared to all other groups. At 7 days, the PRF had thicker trabeculae (p = 0.04). At 28 days, the positive control and PRF showed thicker trabeculae than the negative control (p = 0.02).

These results indicate the most positive responses of the bone of MRONJ-induced lesions after PRF and PBM treatments, accelerating the process of bone neoformation and regeneration in MRONJ.