A single dose of amoxicillin and dexamethasone for prevention of postoperative complications in third molar surgery: a randomized, double-blind, placebo controlled clinical trial.

BACKGROUND: The aim of this study was to assess the efficacy of a single prophylactic dose of amoxicillin and/or dexamethasone in preventing postoperative complications (PC) after a surgical removal of a single mandibular third molar (M3). METHODS: This study is a randomized, placebo controlled clinical trial. Four groups were included: Group 1 (G1) included a prophylactic dose of 2 g of amoxicillin and 8 mg of dexamethasone; Group 2 (G2) included a prophylactic dose of 2 g of amoxicillin and 8 mg of placebo; Group 3 (G3) included a prophylactic dose of 8 mg of dexamethasone and 2 g of placebo and; Group 4 (G4) placebo. RESULTS: Fifty patients were included. It was observed one case of alveolar infection (2%) and two of alveolar osteitis (4%) resulting in three PC (6%). No statistical differences were observed between therapeutic groups for development of PC, trismus, pain and edema. The use of antibiotics showed an absolute risk reduction (ARR) for PC development of 3.52% and the number needed to treat (NNT) was 29. CONCLUSION: Prophylactic antibiotics and corticoid in a single dose regimen did not bring any benefit on M3 surgeries.