Construction of a 3D printed, human gingival MSC seeded alveolar bone implant

Abstract

Background/objective(s)/introduction: Tissue engineered scaffolds fabricated by 3D printing promises to enhance the success rate in alveolar bone augmentation. The aim of this study was to construct and characterize a 3D printed poly(epsilon-caprolactone; PCL) scaffolds treated with bone morphogenetic protein 2 (BMP-2) and carrying human gingival mesenchymal stem cells (hGMSCs) for potential use in the augmentation of alveolar bone.Materials and methods: PCL scaffolds with defined pore geometry were fabricated by 3D printing using fused deposition modeling (FDM) and treated with O2 plasma to enhance BMP-2 and cell adhesion. The scaffolds were characterized by compression testing, scanning electron microscopy (SEM), and water contact angle measurement. BMP-2 was bound to the surface, and hGMSCs from gingival connective tissue were seeded onto the scaffolds. BMP-2 was quantified by elisa. The cells were identified as stem cells based on their differentiation capacity and immunophenotypic profile. Osteogenic differentiation on BMP-2 bound scaffolds was assessed using alkaline phosphatase (ALP) activity and calcium deposition assays.Results: Compressive modulus of the PCL scaffolds (73.2 +/- 17.1 MPa) was close to human alveolar bone (96.2 +/- 40.6 MPa). SEM revealed a porous design with continuous struts, creating an average pore size of 400 & micro;m and zig-zag channels suitable for cell infiltration and adhesion. O2 plasma treatment decreased the water contact angle from 110 degrees +/- 4 degrees to 59 degrees +/- 2 degrees, indicating improved surface hydrophilicity. ELISA showed that over 98% of BMP-2 remained bound to the scaffold for 28 days, indicating prolonged growth factor presence during cell culture. Within the environment created, BMP-2 bound scaffolds led to a threefold increase in ALP activity and higher calcium deposition compared to controls, confirming enhanced osteogenic differentiation.Conclusion(s): 3D printed PCL scaffolds functionalized with BMP-2 and seeded with hGMSCs exhibited highly improved in vitro osteogenic properties which promises to improve alveolar bone augmentation results.