Dynamics of hydroxyapatite performance in natural composites: A narrative review on its synthesis and applications

Abstract

The wide distribution of HAp with natural and synthetic polymers and other minerals in composite forms made it give multiple properties. Knowing the varied properties of HAp in different composites helps to customize its degradation rate depending on permanent and temporary applications. This helps to reduce the infection rate and enhance compatibility. The main objective of this review is to help the medical professionals select HAp based on varied properties of HAp when combined with synthetic and natural polymers and minerals in composite form. This may help them to choose the composite of HAp based on the intended application. The current review discussed the structure of HAp to facilitate the bone replacement, the mechanism by which it replaces the bone, and the property enhancement with synthetic and natural polymers and minerals. Therefore, a new dimension of the HAp and its synergistic effects based on the cross-linkers, cofactors, and adjuncts such as natural polymers, cross-linked polymers, and other dopants used for scaffolds are discussed. It gives the detailed structure and properties of HAp when it forms a composite with synthetic and natural polymers suited for various applications. By reading this review, the reader may get some knowledge in selecting the composite based on the requirement and needed property. If the mechanical strength is crucial for load bearing, HAp with bioceramics or polymers may be selected. Similarly, for faster osseointegration and antimicrobial properties, the composites with bioactive ions are preferred. This will enhance the performance of the implant with patient comfort and the anatomical site of application. This review provides the key finding of property change in HAp when combined with synthetic and natural polymers and with mineral dopants. This will help to customize HAp while synthesizing and help to reduce the rejection rate.