Bone regeneration potential of poly(ε-caprolactone)/β-tricalcium phosphate polymer scaffolds compared with collagen-reinforced synthetic and xenogenic scaffolds in rabbit calvarial defects

Abstract

Sufficient alveolar bone volume is crucial for implant placement; however, ridge defects caused by extraction, infection, or trauma often compromise outcomes. Although guided bone regeneration with particulate grafts and membranes is common, it is limited by graft loss and inadequate space maintenance. To overcome these drawbacks, three-dimensional scaffolds have been introduced. This study compared the performance of deproteinized bovine bone mineral (DBBM), synthetic block (SB), and polycaprolactone/ β-tricalcium phosphate (PCL–TCP) scaffolds in rabbit calvarial defects. Standardized defects were treated with SB, DBBM, PCL– TCP scaffolds, or left empty as controls. Micro-computed tomography and histological analyses were performed at 2 and 6 weeks. At 2 weeks, bone volume was significantly higher in the SB (40.42±5.29 mm3) and DBBM (37.32±9.00 mm3) groups compared with the control (10.68±3.04 mm3) and PCL–TCP (8.12±1.27 mm3) groups. At 6 weeks, the SB scaffold (80.24±12.81 mm3) showed the largest bone volume, followed by DBBM (62.18±6.91 mm3), both exceeding the control (41.90±5.40 mm3), whereas the PCL–TCP scaffold (29.73±4.89 mm3) exhibited the lowest. Histology confirmed robust bone formation in SB and DBBM groups, but limited and irregular deposition in the PCL–TCP group. Within the limitations of this study, SB and DBBM scaffolds provided stable and predictable regeneration, whereas the PCL–TCP scaffold showed inferior osteogenic performance despite structural stability. Further optimization of polymer scaffold design and surface properties is required to enhance biological outcomes.