title: Clinical and histomorphometrical study on titanium dioxide-coated external fixation pins.
abstract: BACKGROUND
  Pin site infection is the most common and significant complication of external fixation. In this work, the efficacy of pins coated with titanium dioxide (TiO(2)) for inhibition of infection was compared with that of stainless steel control pins in an in vivo study.
  
  
  METHODS
  Pins contaminated with an identifiable Staphylococcus aureus strain were inserted into femoral bone in a rat model and exposed to ultraviolet A light for 30 minutes. On day 14, the animals were sacrificed and the bone and soft tissue around the pin were retrieved. The clinical findings and histological findings were evaluated in 60 samples.
  
  
  RESULTS
  Clinical signs of infection were present in 76.7% of untreated pins, but in only 36.7% of TiO(2)-coated pins. The histological bone infection score and planimetric rate of occupation for bacterial colonies and neutrophils in the TiO(2)-coated pin group were lower than those in the control group. The bone-implant contact ratio of the TiO(2)-coated pin group was significantly higher (71.4%) than in the control pin group (58.2%). The TiO(2) was successful in decreasing infection both clinically and histomorphometrically.
  
  
  CONCLUSIONS
  The photocatalytic bactericidal effect of TiO(2) is thought to be useful for inhibiting pin site infection after external fixation.
authors: Department of Orthopedic Surgery, Graduate School of Medicine, Nagasaki University, Nagasaki, Japan. jj20110043@cc.nagasaki-u.ac.jp
authors: Hironobu
authors: H
authors: Koseki
authors: Tomohiko
authors: T
authors: Asahara
authors: Takayuki
authors: T
authors: Shida
authors: Itaru
authors: I
authors: Yoda
authors: Hidehiko
authors: H
authors: Horiuchi
authors: Koumei
authors: K
authors: Baba
authors: Makoto
authors: M
authors: Osaki
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000737:chemistry*; D001850:Bone Diseases, Infectious / Q000517:prevention & control; D001858:Bone Nails; D016267:External Fixators; D005260:Female; D005269:Femur / Q000601:surgery; D006651:Histocytochemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D013203:Staphylococcal Infections / Q000517:prevention & control; D013211:Staphylococcus aureus / Q000187:drug effects; D013499:Surface Properties; D014025:Titanium / Q000008:administration & dosage* / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; C009495:titanium dioxide; D014025:Titanium
keywords: Staphylococcus aureus; bactericidal activity; external fixation; titanium dioxide