The composite of hydroxyapatite and calcium sulphate: a review of preclinical evaluation and clinical applications

Abstract

Recent publications have shown that the combination of α-calcium sulfate hemihydrate, the densest form of hydrates and hydroxyapatite (HA) particles gives good clinical outcome in various applications. It has large potential as bone substitute since the material transforms to bone throughout the entire volume and not only by creeping substitution, from the surface toward the inside. Release of important proteins for osteogenesis has been observed around implanted material and is speculated to be due to fast dissolution of the calcium sulfate phase in combination with the osteoconductive and bioactive nature of HA. In diabetic foot infection, the osteoconductive HA/calcium sulfate material has been successfully used loaded with antibiotics and since it is injectable, the application is minimally invasive, easy and precise. It is a bone substitute for the future.

Keywords::

• biocompatibility
• bone healing
• bone substitute
• calcium sulphate
• clinical
• hydroxyapatite
• osteoconductive
• preclinical
• porosity
• resorbable

Acknowledgements

The authors thank the Foundation for Assistance to Disabled People in Skåne (Stiftelsen för bistånd åt rörelsehindrade i Skåne; Region Skåne), The Faculty of Medicine, Lund University.

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• • The demand of bone substitutes is increasing with an aging population, and good alternatives to autograft bone are needed, where hydroxyapatite (HA)/calcium sulfate composite is a potential choice.

• • HA/calcium sulfate composite is substituted by bone throughout the entire material and not only from the surface toward the center of the defect.

• • Good clinical outcome in various applications such as osteotomies, cyst and defect filling, skull deformations, vertebroplasty and diabetic foot infections have been reported.

• • Good bone healing was demonstrated and it was concluded by several authors that the HA/calcium sulfate bone substitute is a safe, effective, easy to use alternative to autograft.

• • Drug release in addition to osteoconductivity provides a unique alternative for treatment of bone and joint prosthetic infections.