Carbonate Apatite as a Scaffold for Periodontal Regeneration Cell Therapy

Objectives: The purpose of this study was to clarify the efficacy of carbonate apatite (CO₃Ap) as a scaffold in autologous transplantation of adipose tissue-derived multi-lineage progenitor cells (ADMPC) for periodontal tissue regeneration.
Methods: The effects of CO₃Ap on cellular functions of ADMPCs were evaluated in vitro. Human ADMPCs cultured on disc-shaped CO₃Ap were compared with those cultured-on tissue culture plates as a control. The comparison between the two groups was performed in terms of cell morphology, proliferation, cytodifferentiation, and humoral factor secretion. In addition, the efficacy of ADMPC transplantation with CO₃Ap as a scaffold for periodontal tissue regeneration was evaluated using a canine periodontitis model. One-wall intrabony defects were surgically created on mesial sides of bilateral mandibular first molars and autologous ADMPC transplantation was performed with CO₃Ap as a scaffold. Twelve weeks after the transplantation, periodontal tissue regeneration at the test sites was evaluated by micro-computed tomography and histological analysis.
Results: ADMPCs cultured on CO₃Ap disks showed comparable cell morphology, differentiation, and humoral factor secretion, but increased the proliferation, compared with those cultured on tissue culture plates. In vivo analysis revealed that auto-transplantation of ADMPCs and CO₃Ap resulted in significant alveolar bone regeneration compared with sham operation or CO₃Ap alone sites. Additionally, histological analysis demonstrated new cementum formation on the root surface of ADMPC and CO₃Ap-transplanted sites. No undesirable healing, such as root resorption or ankyloses, was observed at any examined site.
Conclusions: This study suggests that CO₃Ap supports ADMPC functions and the use of CO₃Ap as a scaffold in autologous ADMPC transplantation therapy induces significant periodontal tissue regeneration in a canine periodontitis model.