Preparation of β-Ca3(PO4)2/Poly(D,L-lactide) and β-Ca3(PO4)2/Poly(ε-caprolactone) Biocomposite Implants for Bone Substitution

Abstract

Highly permeable macroporous implants of various architectures for bone grafting have been fabricated by thermal extrusion 3D printing using highly filled β-Ca₃(PO₄)₂/poly(D,L-lactide) (degree of filling up to 70 wt %) and β-Ca₃(PO₄)₂/poly(ε-caprolactone) (degree of filling up to 70 wt %) composite filaments. To modify the surface of the composite macroporous implants with the aim of improving their wettability by saline solutions, we have proposed exposing them to a cathode discharge plasma (2.5 W, air as plasma gas) in combination with subsequent etching in a 0.5 M citric acid solution. It has been shown that the main contribution to changes in the wettability (contact angle) of the composites is made by the changes produced in their surface morphology by etching in a low-temperature plasma and citric acid. An alternative approach to surface modification of the composites is to produce a carbonate hydroxyapatite layer via precipitation from a simulated body fluid solution a factor of 5 supersaturated relative to its natural analog (5xSBF).