Antibiotics to Prevent Infections Following Third Molar Extractions. Meta-Analysis.

Objectives: To determine whether antibiotic treatment is effective in the prevention of postoperative infection following third molar extractions
Methods: Design: Systematic review and meta-analysis. Data sources: Pubmed, Cochrane, Science Direct, Ovid Medline and Google, key words used: “ infection”, “antibiotic”, “third molar”, “alveolitis”, “wisdom tooth”, “dry socket” and “clinical trial”. Study selection: We only included randomised placebo-controlled double–blind clinical trials with antibiotic prophylaxis in patients undergoing third molar extraction for any indication, between January 2004 and September 2014. We followed the recommendations proposed by the Meta-Analysis Reporting Group. We used the statistical program Review Manager version 5.2. The statistical technique was Mantel-Haenszel. We calculated risk ratios (RR) and 95% confidence intervals (CI) using random-effects models.
Results: This review included 11 clinical trials with a total of 1905 third molars extracted. The outcome variable included infection and dry socket. The use of antibiotic versus placebo reduced the risk of infection by approximately 65%.: RR 0.35 95% CI (0.23, 0.50), P< 0.0001 NNT (range 10- 18), we had to treat between 10 and 18 patients with antibiotic to prevent infection after a third molar extraction. In five clinical trials patients were treated with amoxicillin, (RR 0.4095% CI 0.16 to 1) and in three trials with amoxicillin/clavulanic RR 0.21( 95% CI 0,12 0,40). In nine studies, the antibiotic was administered preoperatively (RR 0.45 (95% CI 0.27 to 0.75) P=0.002. in onl 3 postoperatively (RR 0.15 (95% CI 0.07 to 0.32) P < 0.00001 Antibiotics are associated with an increase in generally mild transitory adverse effects compared to placebo (RR 1.58 (95% CI 0.67 to 3.76)
Conclusions: Routine prescription of antibiotics to prevent post-extraction infection does not seem to be indicated, being less effective the use of amoxicillin than amoxicillin / clavulanic and preoperatively than postoperatively