Histomorphometric Evaluation of Non-Thermal Plasma-Treated Xenogenic Bone Graft for Enhanced Bone Regeneration in a Rabbit Calvarial Defect Model

When placing dental implants, xenografts are most commonly used clinically to compensate for the insufficient bone volume of patients. However, xenografts have limitations including low osteoinductive capacity and prolonged healing time. This study aimed to determine whether non-thermal plasma treatment could enhance the regenerative performance of bovine cancellous bone graft (SANTA-OSS®) in a rabbit calvarial defect model. Twenty-four adult male New Zealand white rabbits received bilateral 8 mm critical-size calvarial defects. One defect was filled with untreated SANTA-OSS (control) and the contralateral defect with plasma-treated SANTA-OSS using the ACTILINK™ Reborn device. Animals were sacrificed at 2, 4, and 8 weeks (n = 8 per group) for histomorphometric analysis. The plasma-treated group showed significantly higher new bone area (14.12 ± 0.69%, 18.93 ± 0.68%, and 32.72 ± 0.61% at 2, 4, and 8 weeks) than the control at all time points (p < 0.05). In addition, the experimental group exhibited accelerated graft resorption, larger bone marrow area, greater blood vessel area, and more TRAP-positive osteoclasts compared with the control (p < 0.05). Within the limitations of this study, non-thermal plasma treatment significantly enhanced new bone formation and promoted favorable graft remodeling, while also accelerating graft resorption, increasing bone marrow area, and improving vascularization. These findings suggest that simple chairside plasma activation can improve the regenerative performance of xenografts.