title: Effect of clinical factors on bacterial contamination of bone chips collected during implant surgery.
abstract: OBJECTIVE
  The objective of this study was to investigate the relationship between various clinical factors and bacterial contamination of bone chips (BC) collected during dental implant surgery and to elucidate how bacterial contamination might be minimized.
  
  
  METHODS
  Implants were installed in 55 partially edentulous patients (36 men and 19 women), among whom the relationship between various clinical factors and bacterial contamination of BC collected by bone trap was investigated in 37. The effect of rinsing with a saline on BC was determined in 18 patients. Number of contaminating microorganisms was expressed as colony-forming units (CFUs).
  
  
  RESULTS
  CFUs in the maxilla were lower than those in the mandible (P < 0.01). CFUs at the incisors or canines were lower than those at the premolars or molars (P < 0.01). Logistic regression analysis revealed a relationship between average bacterial count and duration of surgery (odds ratio, 1.046; 95% CI, 1.012-1.081). Rinsing of BC reduced bacterial contamination.
  
  
  CONCLUSIONS
  Duration of surgery is a major clinical factor affecting contamination risk in BC, and rinsing of BC with a sterile saline solution reduces bacterial number.
authors.affiliation: *Private Practice in Implant Dentistry, Chiba, Japan. †Professor and Chairman of Department of Epidemiology and Public Health, Tokyo Dental College, Chiba, Japan. ‡Professor of Department of Microbiology, Tokyo Dental College, Chiba, Japan. §Professor and Chairman of Department of Microbiology, Tokyo Dental College, Chiba, Japan.
authors.forename: Taketo
authors.initials: T
authors.lastname: Koga
authors.forename: Takashi
authors.initials: T
authors.lastname: Matsukubo
authors.forename: Katsuji
authors.initials: K
authors.lastname: Okuda
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Ishihara
mesh_terms: D000328:Adult; D000368:Aged; D058491:Bacterial Load; D003481:Cuspid / Q000382:microbiology / Q000601:surgery; D003758:Dental Implantation, Endosseous / Q000009:adverse effects / Q000382:microbiology* / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D007180:Incisor / Q000382:microbiology / Q000601:surgery; D007576:Jaw, Edentulous, Partially / Q000601:surgery; D008297:Male; D008334:Mandible; D008437:Maxilla; D008875:Middle Aged; D008963:Molar / Q000382:microbiology / Q000601:surgery; D012307:Risk Factors; D013234:Stem Cells; D013530:Surgical Wound Infection / Q000209:etiology*; D013997:Time Factors