Hydroxyapatite-Barium Titanate Biocoatings Using Room Temperature Coblasting

Abstract

The use of orthopaedic and dental implants is expanding as a consequence of an ageing population and also due to illness or trauma in younger age groups. The implant must be biocompatible, bioactive and interact favourably with the recipient’s bone, as rapid osseointegration is key to success. In this work, Ti-6Al-4V plates were coated using the CoBlastTM technique, with hydroxyapatite (HAp) and HAp/BaTiO3 (barium titanate, BT) non-piezoelectric cubic nanopowders (HAp/cBT) and piezoelectric tetragonal micropowders (HAp/tBT). The addition of BT, a piezoelectric ceramic, is a strategy to accelerate osseointegration by using surface electric charges as cues for cells. For comparison with commercial coatings, plates were coated with HAp using the plasma spray technique. Using XRD and FTIR, both plasma spray and CoBlastTM coatings showed crystalline HAp and no presence of by-products. However, the XRD of the plasma-sprayed coatings revealed the presence of amorphous HAp. The average surface roughness was close to the coatings’ thickness (≈5 μm for CoBlastTM and ≈13 μm for plasma spray). Cytotoxicity assays proved that the coatings are biocompatible. Therefore, it can be concluded that for HAp-based coatings, CoBlastTM is a viable alternative to plasma spray, with the advantage of facilitating room temperature addition of other ceramics, like piezoelectric BaTiO3.

In Vitro Characterization of Doped Bioglass 45S5/HAp Coatings Obtained by CoBlastTM Deposition

“…The results obtained are corroborated by the findings previously described by Dias et al where HA coatings by CoBlast TM were viable at concentrations equal or lower than 1 cm 2 /mL [48].…”

“…CoBlast TM was the method used to coat the metal substrates due to its room temperature conditions, the one-step surface preparation, and deposition process. Furthermore, this method is able to coat components with a variety of geometries [19,48].…”