A biphasic scaffold for simultaneous alveolar bone and periodontal ligament regeneration

Abstract

This study describes the design of a biphasic scaffold composed of a Fused Deposition Modeling scaffold (bone compartment) and an electrospun membrane (periodontal compartment) for periodontal complex regeneration. This strategy combined osteoblast impregnated in the bone compartment and multiple periodontal ligament (PDL) cell sheets on the electrospun membrane. After 21 days in culture the osteoblasts deposited mineralized matrix in the bone compartment and the cell sheets formed of a PDL-like tissue. The scaffolds were placed onto a dentin block and implanted in a rodent subcutaneous model for 8 weeks. In the bone compartment a more intense alkaline phosphatase staining was observed with higher bone density as shown by lCT, when the scaffold contained osteoblasts. A thin mineralized cementum- like tissue was deposited on the dentin surface for the groups with multiple PDL cell sheets (as observed by H&E and Azan staining). These groups showed a better attachment of PDL-like tissues onto the dentin block compared with the scaffold without cell sheets. Immunohistochemistry revealed the presence of cementum protein 1 (CEMP1), a specific marker for cementum, at the interface between PDL and the dentine blocks. These results demonstrated that the combination of multiple PDL cell sheets and a biphasic scaffold allows the simultaneous delivery of the cells necessary for in vivo regeneration of alveolar bone, periodontal ligament and cementum.