Poly-ɛ-caprolactone/multi-wall carbon nanotube composites as osteoinductive scaffolds for alveolar bone regeneration

Designing scaffolds to promote alveolar bone regeneration is a major challenge in dental practice. Among the desired properties of scaffolds, biocompatibility is crucial. Multi-walled carbon nanotubes (MWCNTs) possess high surface area and mechanical strength, enhancing the osteogenic properties of poly-ɛ-caprolactone (PCL). Therefore, this study evaluated the osteogenic potential of PCL/MWCNT scaffolds by incorporating varying weight percentages of MWCNTs (0.5-3 wt.%).

This study fabricated the scaffolds using a solvent-casting/particulate-leaching technique. Their physical and chemical properties were evaluated using contact angle (CA), porosity, pore size distribution, and Raman spectroscopy. In vitro biocompatibility was assessed via 3-(4,5-dimethylthiazole-2-Y1)-2,5-diphenyltetrazolium bromide (MTT) and alkaline phosphatase (ALP) assays using osteoblast-like cells (MG-63), and cell morphology cell morphology was observed using scanning electron microscopy (SEM).

The addition of MWCNTs to scaffolds improved their hydrophilicity and maintains a high porosity (>85 %) in most formulations. The Young's modulus (0.15-2.32 GPa) of PCL/MWCNT scaffolds containing different weight percentages of MWCNTs was comparable to that of human alveolar bone (1.0-3.3 GPa). PCL/MWCNT scaffolds containing 3 wt.% MWCNT exhibited the highest biocompatibility across all time points (days 1, 4, and 7). ALP activity, a marker of osteogenic differentiation, increased significantly over time, particularly at higher weight percentages MWCNT.

The PCL/MWCNT scaffold, especially at a 3 wt.% MWCNT, demonstrated excellent biocompatibility, porosity, and osteoinductive potential, making it a promising candidate for alveolar bone tissue engineering.