Nanocoating for Surgical Implants – Hydroxyapatite on Zirconia

By Staff Writers

Topics Covered

HA Coating of Zirconia Implants
Improved Protein Adsorption and Cell Attachment
Faster Osseointegration
About Promimic AB


The HAnano Surface is a unique hydroxyapatite (HA) coating material due to its innovative coating process. Measuring just 20 nm, the material is very thin and can be applied to any type of implant material, thanks to the novel wet chemical coating technology.

Presence of HAnano Surface has been shown to improve bone growth and thus speeds up osseointegration. The coating also enhances the anchoring strength of the implant.

HAnano Surface on Zirconia Implants

Zirconia is an implant material that has high resistance to corrosion, wear and fractures and hence can be used as a white colored alternative to conventional metal-based implants. When the HAnano Surface is applied to a Zirconia implant, it generates an attractive combination of the bioactivity of nanometer-sized HA and the mechanical properties of substrates.

The procedure of the HAnano Surface coating is optimized so as to preserve the underlying surface structure. The technique is also optimized for the porous structures having a particular surface topology. Through this coating technique, a uniform layer of HA is produced over the entire surface of the implant, both on the inside and outside of pores without actually affecting the porosity.

Figure 1. The HAnano Surface consists of crystalline needle-shaped, nanometer sized hydroxyapatite particles, which perfectly follow the structure of the implant surface.

Improved Protein Adsorption and Cell Attachment

Zirconia is a hydrophobic material, but when it is coated with the HAnano Surface a super-hydrophilic surface is generated. The coating creates a nanostructure which is extremely advantageous with respect to the surface’s wetting behaviour, which is of importance for improved cell attachment and protein adsorption. Even after a period of five months, the contact angle of the coated Zirconia remains at <10 0, as compared to 100 0 for uncoated Zirconia. The HAnano Surface comprises contains nanometer-sized HA particles, which resemble the natural bone minerals and produce a known surface for bone cells.

Figure 2. Difference in wettability between an uncoated Zirconia implant (left image) and a HAnano Surface coated Zirconia implant (right image)

Faster Osseointegration

The HAnano Surface has been assessed and proven in more than 10 pre-clinical in vivo studies. Results from these studies show that coating of implants with HA coating promotes an enhanced biological response. When the HAnano Surface is applied to a Zirconia implant, the surface is changed from biocompatible to osteoconductive. Through this osteoconductive surface, bone cells are attracted to the implant and the thin layer of HA considerably enhances the growth of bone cells thus leading to a faster osseointegration and stronger anchoring of the implant.


From the above discussion, it is evident that when ceramic implants are coated with the HAnano Surface, a super-hydrophilic implant surface is formed. Furthermore, HAnano Surface creates a larger interfacial contact area, changes the implant’s surface from biocompatible to osteoconductive, speeds up osseointegration, and improves the anchoring strength of the implant.

About Promimic AB

Promimic is a biomaterial company founded in 2004 as a spin-off from research performed at Chalmers University of Technology in Gothenburg, Sweden. The company develops and markets a new generation of implant surface modifications and synthetic bone based on a patented method for production of nano sized hydroxyapatite. Promimic has an innovative and experienced organization that continuously is working on new ways to improve surface modification and coating of new materials.

  • HAnano Surface is a unique implant surface which dramatically accelerates osseointegration. The surface can be applied onto various types of materials - including metals, ceramics and polymers - regardless of its dimensions and structure. The HAnano Surface has received 510(k) approval by the FDA (American Food and Drug Administration), which applies to the area of dental implants.
  • HAnano Bone is a new generation of synthetic bone. The unique composition of HAnano Bone allows it to be mouldable over extended periods of time.

This information has been sourced, reviewed and adapted from materials provided by Promimic AB.

For more information on this source, please visit Promimic AB.


Date Added: Aug 29, 2013 | Updated: Sep 5, 2013
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