Surface Corrosion of Nanoscaled Hydroxyapatite During an In Vivo Experiment

Abstract

Hydroxyapatite (HA) is widely used as a bioactive ceramics as it forms a chemical bond with bone. However, the drawback to using this material is its inferior mechanical properties. In this research, surface corrosion and disintegration of nanoscaled HA in a dog were studied, and the mechanism by which phase-pure HA dissolved in vivo was investigated. Biological properties of HA in vivo are affected by the grain-boundary dissolution followed by a surface corrosion and microstructural disintegration. This kind of dissolution process, apparently evidenced at the grain boundary, causes particle generation, which indicates that both long-term bone in-growth and mechanical properties can dramatically deteriorate. Implant dissolution by osteoclasts in vivo is also observed on the surface of hydroxyapatite. Implant surface showed an aggressive corrosion by an osteoclast resorption. Severe and deeper dissolution underwent close to osteoclast resulting in formation of smaller and more round particle shape.

Bone Mineral Crystallinity Governs the Orchestration of Ossification and Resorption during Bone Remodeling

“…22 In turn, the osteoclastic resorption of bone proceeds via the secretion of protons across the ruffled border membrane and into the extracellular resorbing compartment in the first step. 23 This is followed by the vesicular entrapment and phagocytic engulfment of nanoparticulate mineral particles and finer atomic clusters generated during the dissolution of the mineral, 24 with such nanoparticles being localizable on the basolateral side of the ruffled border membrane and in deeper regions of osteoclasts. 25 These biological mechanisms of growth and dissolution are extensions of the more fundamental chemical mechanisms applying to the same processes in acellular media, which are such that, per eq 1, always proceed through the formation of nanoparticles and finer atomic clusters as intermediates.…”

The Association of Nanostructured Carbonated Hydroxyapatite with Denatured Albumin and Platelet-Rich Fibrin: Impacts on Growth Factors Release and Osteoblast Behavior

“…Due to its osteoconductive and biocompatible properties, hydroxyapatite (HA) is widely used as a bioceramic for bone replacement applications. The incorporation of carbonate into nanostructured HA causes significant changes in its physicochemical properties, resulting in increased in vivo dissolution rates and enabling the production of bone substitutes with greater resorption [34,35]. In this study, the ultrastructure of nCHA spheres was evaluated by scanning electron microscopy (SEM), enabling to observe a highly porous surface topography.…”

Mineralized collagen/Mg–Ca alloy combined scaffolds with improved biocompatibility for enhanced bone response following tooth extraction

“…Hydroxyapatite (HA) is the main inorganic component of natural bone, and it is also a bioceramic material with good biological activity and biocompatibility [5]. HA can be tightly bound to the surrounding bone through the exchange of calcium and phosphorus ions, and it is a very good performance for bone repair materials [6,7]. Nano-hydroxyapatite/collagen (NHAC) is the composite of type I collagen and nano-hydroxyapatite.…”