An observational study of alveolar-derived autologous blood clot used in regenerative endodontic treatment for immature permanent teeth with pulp necrosis.

OBJECTIVES

This study introduces the alveolar-derived autologous blood (ADAB) clot, obtained by maxillary alveolar bone puncture, as a novel scaffold for regenerative endodontic treatment (RET). The purpose of this study is to verify the feasibility of using ADAB clots in RET by evaluating their cellular content, postoperative pain intensity, and clinical outcomes in the management of immature permanent teeth with pulp necrosis.

MATERIALS AND METHODS

Blood routine examinations were performed to analyze the cell content of peripheral venous blood (PVB) and ADAB. Postoperative pain intensity scores were recorded using the Numerical Rating Scale (NRS) at four time points: upon complete recovery from anesthesia, and at 12, 24, and 48 h postoperatively. Five immature premolars with pulp necrosis were treated by RET with ADAB clots. Radiographic root area (RRA) was analyzed using ImageJ software on oral radiographs obtained immediately after treatment and at the final follow-up (6-18 months).

RESULTS

The percentage difference in cell types between two groups (n = 8 per group) were not significant, except for blood platelets (PLT). The PLT count in the ADAB group (133.38 ± 119.62) was approximately half that of the PVB group (268.88 ± 52.82). Postoperative pain (n = 9) was predominantly mild upon anesthesia recovery and at 12 h postoperatively, while the majority of participants reported no pain at 24 and 48 h postoperatively. The mean RRA (0.50 ± 0.11) in the final recall radiographs was significantly larger than that in the immediate postoperative radiographs (0.35 ± 0.16) (P = 0.046 < 0.05).

CONCLUSION

Based on this study, the ADAB clot shows potential as an alternative scaffold for RET. Because it can be obtained via maxillary terminal alveolar bone paracentesis with mild postoperative pain intensity and successfully promotes root regrowth. However, the coagulation time of ADAB may be longer than that of PVB, and root regrowth outcomes appear to depend on the developmental stage of the tooth. Hence, further clinical trials are necessary to comprehensively evaluate the clinical efficacy of the ADAB clot.

CLINICAL RELEVANCE

Compared to autologous platelet concentrates (APCs) derived from PVB, ADAB clots offer advantages in RET, especially in cases where periapical bleeding is insufficient to fill the root canals. ADAB clots can be prepared independently by dentists without the need for a qualified nurse for blood collection or specialized centrifugation equipment. Furthermore, the volume of blood required to fabricate an ADAB clot is less than that needed for APCs from PVB.