Synthesis, Characterization, and 3D Printing of an Isosorbide-Based, Light-Curable, Degradable Polymer for Potential Application in Maxillofacial Reconstruction

Abstract

Although emergence of bone tissue engineering techniques has revolutionised the field of maxillofacial reconstruction, the successful translation of such products, especially concerning larger sized defects, still remains a significant challenge.Light curable methacrylate-based polymers have ideal properties for bone repair. These materials are also suitable for 3D printing which can be applicable for restoration of both function and aesthetics. The main objective of this research was to synthesise a mechanically stable and biologically functional polymer for reconstruction of complex craniofacial defects. The experimental work initially involved synthesis of (((3R,3aR,6S,6aR)-hexahydrofuro[3,2b]furan-3,6-diyl)bis(oxy))bis(ethane-2,1-diyl) bis((4-methyl-3-oxopent-4-en-1-yl)carbamate), CSMA-1, and ((((((((((((3R,3aR,6S,6aR)-hexahydrofuro[3,2-b]furan-3,6diyl)bis(oxy))bis(ethane-2,1 diyl))bis(oxy))bis(carbonyl))bis(azanediyl))bis(methylene))bis(3,3,5-trimethylcyclohexane-5,1-diyl))bis(azanediyl))bis(carbonyl))bis(oxy))bis(ethane-2,1-diyl) bis(2-methylacrylate), CSMA-2; Nuclear Magnetic Resonance (NMR) analysis confirmed formation of the monomers and composite samples were fabricated respectively by exposing 11 mm diameter discs to blue light. Modulus of the tensile elasticity was tested using a biaxial flexural test and the values were found to be between 1 and 3 GPa in CMA-1, CSMA-2 and their composites. In vitro cell culture, using human Bone Marrow Derived Mesenchymal Stem Cells (BMSCs), confirmednon-toxicity of the samples and finally 3D printing allowed direct photo-polymerisation and setting of the bio ink into a mesh-like construct.

Comparative study of photoinitiators for the synthesis and 3D printing of a light-curable, degradable polymer for custom-fit hard tissue implants

“…However, the protons of the urethane groups which link the 20 methacrylate units to Isosorbide, were not seen, which could be due to them being superimposed by other 21 signals. These findings match the 1 H NMR spectra previously recorded by Owji et al[24]…”

“…was synthesised as previously explored in a study by Owji et al [24] and optimised for enhanced mechanical 50 properties. Two different photo initiators, as seen in table 1, camphorquinone (CQ) and phenylbis (2,4,6-A c c e p t e d M a n u s c r i p t trimethylbenzoyl)phosphine oxide) (BAPO) were incorporated to allow polymerisation to take place.…”

“…HA. In comparison, the previous study on CSMA by Owji et al [24] used a reactive filler combination of mono 11 calcium phosphate monohydrate (MCPM) and beta tri-calcium phosphate (TCP) to form the polymer composites.…”

Decellularised scaffolds: just a framework? Current knowledge and future directions

“…Additive manufacturing techniques, including three-dimensional (3D) printing, offer an exciting prospect in the tissue engineering field, as scaffolds with pre-determined shapes and implants that perfectly fit a defect can be fabricated using these techniques. 53 , 54 Furthermore, bioprinting aims to print and pattern cells and ECM material in three dimensions to generate structures similar to tissues and organs. 55 An important consideration in bioprinting is that the printing process must be cytocompatible, thus restricting the choice of materials that can operate in an aqueous or aqueous gel environment.…”

Special Issue: Leaders in Biomedical Engineering

“…Instead of using natural materials, Owji and co-workers studied synthetic light-curable methacrylate-based polymers for 3D printing using isosorbidebased dimethacrylic monomers. 2 These polymers exhibited slow degradation. The stiffness of their constructs could be tuned by the incorporation of CaP powders for reconstruction of craniofacial defects.…”