Improvement of a commercial calcium phosphate bone cement by means of drug delivery and increased injectability

Miguel Castilho; Claus Moseke; Andrea Ewald; Uwe Gbureck; Jürgen Groll; Inês Pires; Jörg Teßmar; Elke Vorndran; Maria Amélia Martins de Almeida; A.C. Branco; R. Colaço; A.P. Serro

Key information

Authors:

Miguel Castilho (Manuel Francisco Costa Pereira); Claus Moseke; Andrea Ewald; Uwe Gbureck; Jürgen Groll; Inês Pires (Inês da Fonseca Pestana Ascenso Pires); Jörg Teßmar; Elke Vorndran; Maria Amélia Martins de Almeida (Maria Amélia Martins de Almeida); A.C. Branco (Ana Catarina Moreno Branco); R. Colaço (Rogério Anacleto Cordeiro Colaço); A.P. Serro (Ana Paula Valagão Amadeu do Serro)

Published in

August 2022

Abstract

The 3D printing technique based on cement powders is an excellent method for the fabrication of individual and complex bone substitutes even in the case of large defects. The outstanding bone remodeling capacity of biphasic calcium phosphates (BCPs) containing hydroxyapatite (HA) as well as tricalcium phosphate (TCP) in varying ratios makes the adaption of powder systems resulting in BCP materials to this fabrication technique a desirable aim. This study presents the synthesis and characterization of a novel powder system for the 3D printing process, intended for the production of complexly shaped BCP scaffolds by a hydraulic setting reaction of calcium carbonate and TCP with phosphoric acid. The HA/TCP ratio in the specimens could be tailored by the calcium/phosphate ratio of the starting powder. The scaffolds could be fabricated with a dimensional accuracy of >96.5% and a minimal macro pore size of 300 μm. Independent of the phase composition the printed specimens showed a microporosity of approximately 68%, while the compressive strength strongly depended on the chemical composition and increased with rising TCP content in the scaffolds to a maximum of 1.81 MPa. Post-treatment of the scaffolds with a polylactic-co-glycolic acid-solution enhanced the mechanical properties by a factor of 8. In vitro studies showed that all BCP scaffolds were cytocompatible and enhanced the cell viability as well as the cell proliferation, as compared with pure TCP. Cell proliferation is even better on BCP when compared to HA and cell viability is in a similar range on these materials