Abstract
Introduction
Tantalum trabecular metal components are increasingly used to reconstruct major bone defects in revision arthroplasty surgery. It is known that some metals such as silver have antibacterial properties. Recent reports have raised the question as to whether Tantalum components are protective against infection in revision surgery. This is based on a retrospective, single institution review, of revision cases comparing tantalum with titanium acetabular implants, which reported a lower incidence of subsequent infection in the tantalum group.
This laboratory study aimed to establish if tantalum had any intrinsic antibacterial properties against planktonic bacteria or ability to inhibit biofilm formation.
Materials and methods
Equal sized pieces of tantalum (Trabecular metal, Zimmer UK) and titanium (Trilogy, Zimmer UK) were sterilised and then incubated with a low dose inoculum of either Staphylococcus aureus or Staphylococcus epidermidis for 24 hours. After serial dilution, colony forming units were quantified on MH agar plates.
To establish the ability to inhibit biofilm formation these tantalum and titanium pieces were then washed twice, sonicated and washed again to remove loosely adhered planktonic bacteria. They were then re-incubated for 24 hours prior to quantifying colony forming units.
All experiments were performed in triplicate
Results
More than 1×108 cfu/ml were observed in both the titanium and tantalum experiments.
After washing and sonication more than 2×107 cfu/ml were observed for both tantalum and titanium groups.
The results were the same for both Staph Aureus and Staph Epidermidis.
Discussion
Compared with titanium controls tantalum did not demonstrate any intrinsic antibacterial activity or ability to inhibit biofilm formation. The intrinsic properties of tantalum do not account for the previously observed reduction in subsequent infection when tantalum was used in the revision procedure.
Conclusion
Tantalum does not have any intrinsic antimicrobial properties or ability to inhibit biofilm formation.