Bonelike Hydroxyapatite Induction by a Gel‐Derived Titania on a Titanium Substrate

TLDR

Gel‑derived titania coatings are applied to commercial pure titanium substrates to improve surface properties. The abundant hydroxyl groups and negative charges on the titania gel surface chemically stimulate bonelike hydroxyapatite induction. In simulated body fluid, the coating induces poorly crystallized, calcium‑deficient, carbonate‑containing hydroxyapatite that incorporates carbonate into the lattice, yielding a bone‑like apatite predicted to enhance bone bonding.

Abstract

Gel‐derived titania coating on commercial pure (c.p.) titanium induces hydroxyapatite formation onto its surface from a simulated body fluid (SBF, a metastable calcium phosphate solution). The induced apatite is similar to bone apatite in that it is poorly crystallized, calcium‐deficient, and carbonate‐containing. Furthermore, the carbonate (CO 2–3 ) groups go into the apatite lattice and lie at the positions of PO 3–4 and OH – to replace these ionic groups, resembling the (CO 2–3 ) groups of bone apatite. Therefore, the apatite induced by the gel‐derived titania is said to be bonelike. A chemical stimulation, stemming from abundant hydroxyl groups and negative charges at the surface of the titania gel, is believed to be responsible for the bonelike apatite induction. The potential of bone‐bonding is predicted for the gel‐derived titania, for it is an efficient bonelike apatite inducer in the SBF.