Topical antibiotic prophylaxis for bacteremia after dental extractions

Current prophylaxis for endocarditis in patients undergoing dental procedures consists of oral administration of amoxicillin. There is concern that the risk of anaphylaxis from systemically administered antibiotics might approach the incidence of endocarditis. Emergence of resistance among bacteria is also favored by systemically administered antibiotics. The present study was designed to assess the efficacy of topical amoxicillin given prophylactically as a mouthwash in reducing the incidence of bacteremia after dental extraction.

Thirty-six outpatients in a dental clinic were randomized in a 3:2:2 ratio to experimental prophylaxis of topical amoxicillin (3 g per mouthwash rinse; 15 patients), standard prophylaxis of oral amoxicillin (3 g in a single dose; 11 patients), or no prophylaxis (10 patients), respectively. Patients were stratified by severity of periodontal disease and number of teeth extracted. Data were analyzed for differences in the incidence of bacteremia by means of the 2-tailed Fisher exact test.

Breakthrough bacteremia after dental extraction was observed in 60% (6 of 10 patients) who received topical amoxicillin and in 89% (8 of 9 patients) who received no prophylaxis (P =.30). By comparison, breakthrough bacteremia after dental extraction was observed in 10% (1 of 10 patients) who received standard prophylaxis with oral amoxicillin (60% vs 10%; P =.05).

Topical amoxicillin decreased the incidence of bacteremia in comparison with no prophylaxis, but statistical significance was not achieved (P =.30). Topical amoxicillin was significantly less effective than standard prophylaxis with oral amoxicillin in decreasing the incidence of bacteremia after dental extractions.