Abstract
Hydroxyapatite (HA) has been widely investigated as scaffolding material for bone tissue engineering, mainly for its excellent biocompatibility. Presently, there is an increasing interest in the composites of hydroxyapatite with bioactive glasses, with the aim to obtain systems with improved bioactivity or mechanical properties. Moreover, modifying the ratio between bioactive glass and hydroxyapatite results in the possibility of controlling the reaction rate of the composite scaffold in the human body. However, high temperature treatments are usually required in order to sinter HA-based composites, causing the bioactive glass to crystallize into a glass-ceramic, with possible negative effects on its bioactivity. In the present research work, a glass composition belonging to the Na2O-CaO-P2O5-SiO2 system, with a reduced tendency to crystallize, is applied to realize HA-based composites. The novel samples can be sintered at a relative low temperature (750 °C) compared to the widely studied HA/45S5 Bioglass® composites. This fact greatly helps to preserve the amorphous nature of the glass, with excellent effects in terms of bioactivity, according to in vitro tests. As a first application, the obtained composites are also tested to realize highly porous scaffolds by means of the standard burning out method.
Highlights
Bone tissue engineering [1,2,3] is an emerging biomedical technology aiming to develop alternative protocols for bone tissue repair and regeneration
The damaged tissue is removed from the patient body and the tissue/scaffold composite is reimplanted in the defect site of the patient, where the scaffold will be resorbed while the cells are producing their own natural extracellular matrix
It should be noted that high temperature treatments may cause the bioactive glass to crystallize into a glass-ceramic prior to complete densification, with possible negative effects on its bioactivity [32]
Summary
Bone tissue engineering [1,2,3] is an emerging biomedical technology aiming to develop alternative protocols for bone tissue repair and regeneration. The cells are seeded on a scaffold [4,5,6], i.e., a proper porous structure which acts as a guide for tissue re-growth in three dimensions, obtaining a living bio-composite system. From this point of view, scaffolds are artificial structures designed as temporary templates for cell adhesion and proliferation. It is highly desirable to optimally control the reaction rate of the scaffold in the human body, which is expected to range from a slightly bioactive behavior to a quick and complete bioresorption with appropriate degradation properties depending on the specific application [12,13]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
