The effect of dental pulp stem cells and L-PRF when placed into the extraction sockets of impacted mandibular third molars on the periodontal status of adjacent second molars: a split-mouth, randomized, controlled clinical trial

To compare the clinical and radiographic effectiveness of dental pulp stem cells (DPSCs) seeded onto L-PRF and L-PRF alone in the extraction socket of mandibular third molars. This study analyzed 13 patients who required surgical removal of impacted bilateral mandibular third molars. The main outcome measures were the probing pocket depth (PPD) and clinical attachment levels (CAL) that were recorded for the adjacent second molars (LM2) at the baseline and 6 months after surgery. The secondary outcomes were radiographic vertical bone loss (VD) and relative bone density (rBD) distal to the LM2. Twenty-six LM2s were evaluated. After 6 months, the L-PRF and L-PRF + DPSC groups showed a significant reduction in PPD (1.65 ± 1.01 mm and 1.54 ± 0.78 mm) and CAL (2.23 ± 1.45 mm and 2.12 ± 0.74 mm), respectively. There was no difference between the groups for any periodontal parameters. No significant differences were found between the groups regarding the VD or rBD at the sixth month. This study found that there was a significant improvement regarding the PPD, CAL, and VD measurements with the application of L-PRF, both alone and with the addition of DPSC, at the extraction socket. DPSC did not significantly contribute to the results compared to L-PRF therapy alone. This study was registered on 23 December 2020 on ClinicalTrials.gov under the number NCT04641533.