A new antimicrobial prophylactic regimen to prevent bacteraemia following dental procedures

Abstract

Purpose: Despite the controversy about the risk of developing bacterial endocarditis of oral origin, numerous Expert Committees in different countries continue to publish prophylactic regimens. To date, the literature is unclear about the role of antimicrobial prophylaxis in the prevention of bacteremia following dental procedures. The aim of this study was to evaluate the efficacy of prophylactic dosage with Amoxicillin (AMX), Clindamycin (CM), a Chlorhexidine (CHX) mouthwash, and a combination of a CHX mouthwash and amoxicillin-clavulanate (AMX-CLV) in the prevention of bacteremia following dental extractions. Methods: A study group composed by 100 adults who required dental extractions under general anaesthesia were randomly assigned to: control group (receiving no prophylaxis), AMX group (receiving 2 g AMX i.v.), CM group (receiving 600 mg CM i.v.), CHX group (receiving a single 0.2% CHX mouthwash for 30 seconds) and CHX/AMX-CLV group (receiving a CHX mouthwash and 1000/200mg AMX-CLV i.v.). Venous blood samples were collected from each patient at 30 seconds, 15 minutes and 1 hour after tooth extractions. Samples were inoculated in BACTEC plus aerobic and anaerobic blood culture bottles, and were processed in the Bactec 9240. The subculture and further identification of the isolated bacteria were performed by conventional microbiological techniques. Results: The prevalences of BDE in the control group, AMX group, CM group, CHX group and CHX/AMX-CLV group were 96/46/85/79/5% at 30 seconds, 64/11/70/29/0% at 15 minutes, and 20/4/22/7/0% at 1 hour later. Streptococci were the most frequently identified bacteria in all groups (40-65%). Conclusions: Amoxicillin and a chlorhexidine mouthwash reduce the risk of bacteremia following dental extractions. Clindamycin prophylaxis was non effective. The new antimicrobial regimen combining a CHX mouthwash and amoxicillin-clavulanate showed the highest efficacy in reducing the prevalence and duration of bacteremia following dental extractions.