Prevention of pin tract infection with titanium-copper alloys

J Biomed Mater Res B Appl Biomater. 2009 Oct;91(1):373-80. doi: 10.1002/jbm.b.31412.

Abstract

The most frequent complication in external fixation is pin tract infection. To reduce the incidence of implant-associated infection, many published reports have looked at preventing bacterial adhesion by treating the pin surface. This study aimed to evaluate the antibacterial activity of a Titanium-Copper (Ti-Cu) alloy on implant infection, and to determine the potential use of the Ti-Cu alloy as a biomaterial. Two forms of Ti-Cu alloys were synthesized: one with 1% Cu and the other with 5% Cu. For analyzing infectious behavior, the implants were exposed to Staphylococcus aureus and Escherichia coli. The reaction of pathogens to the Ti-Cu alloys was compared with their reaction to stainless steel and pure titanium as controls. Both Ti-Cu alloys evidently inhibited colonization by both bacteria. Conversely, cytocompatibility studies were performed using fibroblasts and colony formation on the metals was assessed by counting the number of colonies. Ti-1% Cu alloy showed no difference in the number of colonies compared with the control. External fixator pins made of Ti-Cu alloys were evaluated in a rabbit model. The tissue-implant interactions were analyzed for the presence of infection, inflammatory changes and osteoid-formation. Ti-1% Cu alloy significantly inhibited inflammation and infection, and had excellent osteoid-formation. Copper blood levels were measured before surgery and at 14 days postoperatively. Preoperative and postoperative blood copper values were not statistically different. Overall, it was concluded that Ti-Cu alloys have antimicrobial activity and substantially reduce the incidence of pin tract infection. Ti-1% Cu alloy shows particular promise as a biomaterial.

Publication types

  • Evaluation Study

MeSH terms

  • Alloys / chemistry*
  • Animals
  • Anti-Infective Agents / chemistry
  • Bacterial Infections / prevention & control*
  • Biocompatible Materials / chemistry
  • Copper / chemistry*
  • Cricetinae
  • Cricetulus
  • External Fixators* / adverse effects
  • External Fixators* / microbiology
  • Female
  • Fibroblasts / cytology
  • Fibroblasts / physiology
  • Materials Testing
  • Rabbits
  • Stainless Steel / chemistry
  • Titanium / chemistry*

Substances

  • Alloys
  • Anti-Infective Agents
  • Biocompatible Materials
  • Stainless Steel
  • Copper
  • Titanium