Antibiotics to prevent complications following tooth extractions

BACKGROUND: The most frequent indications for tooth extractions, generally performed by general dental practitioners, are dental caries and periodontal infections. Systemic antibiotics may be prescribed to patients undergoing extractions to prevent complications due to infection. This is an update of a review first published in 2012. OBJECTIVES: To determine the effect of systemic antibiotic prophylaxis on the prevention of infectious complications following tooth extractions. SEARCH METHODS: Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health Trials Register (to 16 April 2020), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2020, Issue 3), MEDLINE Ovid (1946 to 16 April 2020), Embase Ovid (1980 to 16 April 2020), and LILACS (1982 to 16 April 2020). The US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. SELECTION CRITERIA: We included randomised, double-blind, placebo-controlled trials of systemic antibiotic prophylaxis in patients undergoing tooth extraction(s) for any indication. DATA COLLECTION AND ANALYSIS: At least two review authors independently performed data extraction and 'Risk of bias' assessment for the included studies. We contacted trial authors for further details where these were unclear. For dichotomous outcomes, we calculated risk ratios (RR) and 95% confidence intervals (CI) using random-effects models. For continuous outcomes, we used mean differences (MD) with 95% CI using random-effects models. We examined potential sources of heterogeneity. We assessed the certainty of the body of evidence for key outcomes as high, moderate, low, or very low, using the GRADE approach. MAIN RESULTS: We included 23 trials that randomised approximately 3206 participants (2583 analysed) to prophylactic antibiotics or placebo. Although general dentists perform dental extractions because of severe dental caries or periodontal infection, only one of the trials evaluated the role of antibiotic prophylaxis in groups of patients affected by those clinical conditions. We assessed 16 trials as being at high risk of bias, three at low risk, and four as unclear.  Compared to placebo, antibiotics may reduce the risk of postsurgical infectious complications in patients undergoing third molar extractions by approximately 66% (RR 0.34, 95% CI 0.19 to 0.64; 1728 participants; 12 studies; low-certainty evidence), which means that 19 people (95% CI 15 to 34) need to be treated with antibiotics to prevent one infection following extraction of impacted wisdom teeth. Antibiotics may also reduce the risk of dry socket by 34% (RR 0.66, 95% CI 0.45 to 0.97; 1882 participants; 13 studies; low-certainty evidence), which means that 46 people (95% CI 29 to 62) need to take antibiotics to prevent one case of dry socket following extraction of impacted wisdom teeth. The evidence for our other outcomes is uncertain: pain, whether measured dichotomously as presence or absence (RR 0.59, 95% CI 0.31 to 1.12; 675 participants; 3 studies) or continuously using a visual analogue scale (0-to-10-centimetre scale, where 0 is no pain) (MD -0.26, 95% CI -0.59 to 0.07; 422 participants; 4 studies); fever (RR 0.66, 95% CI 0.24 to 1.79; 475 participants; 4 studies); and adverse effects, which were mild and transient (RR 1.46, 95% CI 0.81 to 2.64; 1277 participants; 8 studies) (very low-certainty evidence).  We found no clear evidence that the timing of antibiotic administration (preoperative, postoperative, or both) was important. The included studies enrolled a subset of patients undergoing dental extractions, that is healthy people who had surgical extraction of third molars. Consequently, the results of this review may not be generalisable to all people undergoing tooth extractions. AUTHORS' CONCLUSIONS: The vast majority (21 out of 23) of the trials included in this review included only healthy patients undergoing extraction of impacted third molars, often performed by oral surgeons. None of the studies evaluated tooth extraction in immunocompromised patients. We found low-certainty evidence that prophylactic antibiotics may reduce the risk of infection and dry socket following third molar extraction when compared to placebo, and very low-certainty evidence of no increase in the risk of adverse effects. On average, treating 19 healthy patients with prophylactic antibiotics may stop one person from getting an infection. It is unclear whether the evidence in this review is generalisable to patients with concomitant illnesses or patients at a higher risk of infection. Due to the increasing prevalence of bacteria that are resistant to antibiotic treatment, clinicians should evaluate if and when to prescribe prophylactic antibiotic therapy before a dental extraction for each patient on the basis of the patient's clinical conditions (healthy or affected by systemic pathology) and level of risk from infective complications. Immunocompromised patients, in particular, need an individualised approach in consultation with their treating medical specialist.