title: Prevalence of Surgical Site Infections Following Orthognathic Surgery: A Retrospective Cohort Analysis.
abstract: OBJECTIVE
  The purpose of this retrospective study was to determine the prevalence of surgical site infection (SSI) after orthognathic surgery at the Department of Oral and Maxillofacial Surgery of Capital Health and Dalhousie University (Halifax, NS, Canada).
  
  
  METHODS
  A retrospective chart review of all patients undergoing orthognathic surgery from October 2005 through April 2013 was performed. The outcome variable was SSI. The primary predictor variable was the antibiotic used for prophylaxis. The secondary predictor variables were patient demographics, such as age, gender, medical comorbidities, and smoking status; duration of surgery; wisdom teeth extractions; single-jaw or bimaxillary surgery; and type of surgery. Data also were gathered on the diagnosis of SSIs and the treatment to resolve these infections.
  
  
  RESULTS
  In total, 2,521 patients underwent surgery, and 253 patients did not meet the inclusion criteria; therefore, the charts of 2,268 patients were reviewed (mean ± standard deviation, 26.9 ± 11.7 yr of age). Eight percent of patients developed an SSI. None of the patient demographics was associated with an increased risk for infection. Most initial infections (62%) and most recurrent infections (78%) occurred in the mandible. Twenty-six percent of patients who developed SSIs had recurrent infections after antibiotic treatment. SSIs necessitated hardware removal for 14% of patients. Adverse effects from the antibiotics were seen in 4.2% of patients. Infection was most frequently diagnosed 11 to 15 days postoperatively. The average length of surgery for patients who did not have an SSI was 136 minutes compared with an average of 157 minutes for patients who had an SSI (odds ratio = 1.0051; 95% confidence interval, 1.0026 to 1.0076; P < .001). Wisdom teeth were extracted in 49.6% of the 2,268 cases. The mean SSI prevalence for multiple jaw procedures (9.2%) was significantly higher than that for single surgical procedures (5.3%; P = .0013). Isolated Le Fort surgeries had a significantly lower prevalence of infection compared with the mean prevalence (3.9%; P = .02), whether they were single piece or segmented (3.5 and 4.3%, respectively; P = .98). The prevalence of infection was significantly lower in the cefazolin group (6.2%) compared with the penicillin (14.3%; P < .0001) and clindamycin (10.4%; P < .02) groups.
  
  
  CONCLUSIONS
  The prophylactic use of first-generation cephalosporins, such as cefazolin, appears to be more effective than penicillin and clindamycin for preventing SSIs in orthognathic surgery. In addition, bimaxillary surgery, mandibular procedures, and duration of surgery might demand antibiotic prophylaxis that is more effective. The presence of third molars and patient demographics are not risk factors for SSIs. A prospective randomized controlled study is underway to investigate the findings of this study.
authors.affiliation: Resident, Department of Oral and Maxillofacial Surgery, Capital Health and Dalhousie University, Halifax, NS, Canada. Electronic address: cdavis.omfs@gmail.com.
authors.forename: Clayton M
authors.initials: CM
authors.lastname: Davis
authors.affiliation: Division Head, Department of Oral and Maxillofacial Radiology, Faculty of Dentistry; Assistant Professor, Department of Oral and Maxillofacial Sciences, Capital Health and Dalhousie University, Halifax, NS, Canada.
authors.forename: Curtis E
authors.initials: CE
authors.lastname: Gregoire
authors.affiliation: Dentistry Student and Research Assistant, Capital Health and Dalhousie University, Halifax, NS, Canada.
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Steeves
authors.affiliation: Private Practitioner; Dalhousie University, Halifax, NS, Canada.
authors.forename: Amanda
authors.initials: A
authors.lastname: Demsey
mesh_terms: D000328:Adult; D000367:Age Factors; D019072:Antibiotic Prophylaxis / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D056948:Orthognathic Surgical Procedures / Q000009:adverse effects*; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D013530:Surgical Wound Infection / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology* / Q000209:etiology