ANTIMICROBIAL EFFECTS OF TITANIUM SURFACES WITH

INCORPORATED COPPER

Nadia Ryter (1), Jochen Koeser (1), Waldemar Hoffmann (1, 2), Uwe Pieles (1), Christiane Jung (3), Falko Schlottig (4), Michael de Wild (1)

1. School of Life Sciences, University of Applied Science Northwestern Switzerland;

2. Department of Biomedicine, University of Basel, Switzerland;

3. KKS Ultraschall AG, Medical Surface Center, Steinen, Switzerland;

4. Thommen Medical AG, Waldenburg, Switzerland.

PROJCET OUTLINE

INTRODUCTION

The success of a dental implant depends on the surgical procedure, a good osseointegration and in long term the prevention of peri-implantitis a bacterial inflammation (Lian et al., 2010; Roos-Jansåker et al., 2006). Five up to nine years after the implant placement, implant loosening in the upper and lower jaw was observed in 19 %

and 9 % of the patients, respectively (Renvert et al., 2008). To prevent implant infection through microorganisms and therefore building of biofilm a new nano-structured titanium surface was characterised and its antimicrobial effect on two bacteria strains was tested.

RESULTS

CONCLUSIONS

The spark assisted titanium surface show a rough topography. Micro and macro size copper clusters decorate the surface. The absolute amount of incorporated copper can be quantified. The high lethal copper concentration for E. coli are problematic in comparison to bone cells because they are inhibited as well. The copper release

shows high enough copper concentrations to inhibit or even harm S. aureus. The here obtained in vitro results of the electrochemically modified nano rough titanium surfaces with integrated copper are promising and could lead to a new dental implant surface with antimicrobial effects.

ACKNOWLEDGMENT

This research activities belong to the project “NAPTIS”, a collaborative initiative between the FHNW, the University of Basel, KKS Ultraschall AG and Thommen Medical AG which is funded by the Swiss Nanoscience Institute

REFERENCES

- Jung, C. (2010): Surface properties of titanium implants treated by spark-assisted anodizing European Cells and Materials, 19(Suppl 2):4, 2010

- Lian, Z., Guan, H., Ivanoski, S., Loo, Y.C., Johnson, N.W., Zhang, H. (2010): Effect of bone to implant contact percentage on bone remodelling surrounding a dental implant. Int. J. Oral. Maxillofac. Surg. Vol. 39, Pages 690-698

- Renvert, S., Roos-Jansåker, A.M., Claffey, N. (2008): Non-surgical treatment of peri-implant mucositis and peri-implantitis: a literature review. J Clin Periodontol. Vol. 35, No. 8, Pages 305-315

- Roos-Jansåker, A.M., Lindahl, C., Renvert, H. (2006): Nine- to fourteen-year follow up of implant treatment. Part II: presence of peri-implant lesions. J Cli Peridontol. Vol. 33, Pages 290-295

On the surface, which was produced by spark-assisted anodizing (Jung, 2010), three layers are visible (conversion layer B (�), porous middle layer B (�) and the outermost layer C (�)). Copper is present as micro- and nanometer size particles or agglomerates A.

The quantitative analysis of the copper decorated surfaces lead to a significant correlation of the integrated copper amount in EDX and AAS measurements. This correlation enables to non-destructively determine the different amount of adsorbed copper (different process times) available on the surface by EDX.

In a release experiment, initially copper is liberated using SBF at 37 °C (blue) and subsequently at 80 °C (red) (ASTM F-1980-02). Two exponential phases which were followed by a steady state can be seen. In general less than 10 % of the incorporated copper was released.

The complete inhibitory concentration of copper (red) was determined with 5 µg⋅mL-1 for S. aureus. The lethal dosage for E. coli was determined as 100 µg⋅mL-1 and for bone cells as 60 µg⋅mL-1 (data not shown). The yellow circle indicates less than 20 % of survival of S. aureus.

Poster, 2011 Annual Meeting of the Swiss Society for Biomedical Engineering (SSBE), Bern, Switzerland, on August 22nd - 23rd, 2011.