Recent Advances in Hydroxyapatite-Based Biocomposites for Bone Tissue Regeneration in Orthopedics

Abstract

Bone tissue is a nanocomposite consisting of an organic and inorganic matrix, in which the collagen component and the mineral phase are organized into complex and porous structures. Hydroxyapatite (HA) is the most used ceramic biomaterial since it mimics the mineral composition of the bone in vertebrates. However, this biomimetic material has poor mechanical properties, such as low tensile and compressive strength, which make it not suitable for bone tissue engineering (BTE). For this reason, HA is often used in combination with different polymers and crosslinkers in the form of composites to improve their mechanical properties and the overall performance of the implantable biomaterials developed for orthopedic applications. This review summarizes recent advances in HA-based biocomposites for bone regeneration, addressing the most widely employed inorganic matrices, the natural and synthetic polymers used as reinforcing components, and the crosslinkers added to improve the mechanical properties of the scaffolds. Besides presenting the main physical and chemical methods in tissue engineering applications, this survey shows that HA biocomposites are generally biocompatible, as per most in vitro and in vivo studies involving animal models and that the results of clinical studies on humans sometimes remain controversial. We believe this review will be helpful as introductory information for scientists studying HA materials in the biomedical field.

The Preliminary Assessment of New Biomaterials Necessitates a Comparison of Direct and Indirect Cytotoxicity Methodological Approaches

“…Usually, assessing the cytotoxic or pro-regenerative effect of individual substances do not cause major difficulties, as most of them are water-soluble. But in case of multi-component solid composites, such as chitosan-bioglass composites presented in this study, a different experimental approach is necessary [ 17 , 18 , 19 ]. To fully characterize and assess the biocompatibility of such composites it is crucial to consider each constituent substance, as well as the potential mechanical damage to the cells caused by a contact with the whole material.…”

Characterization of PLA/PCL/Green Mussel Shells Hydroxyapatite (HA) Biocomposites Prepared by Chemical Blending Methods

“…In order to obtain the necessary qualities, various types of biomaterials are combined to create biocomposites. For example, the combination of a polymer matrix (PLA and PCL) with bioactive minerals (HA) produced a biocomposite material with better mechanical properties and prosthesis integration [ 19 ]. As a result, HA and its polymer-based composites have seen widespread use in orthopedic and dental applications.…”

Antibiotic-loaded hydroxyapatite scaffolds fabricated from Nile tilapia bones for orthopaedics

“…It is well-known that HAp has poor mechanical properties. It has low tensile strength with low compressive strength ( Ielo et al, 2022 ). There are reports suggesting that HAp mechanical properties can be improved by blending or coating polymers.…”