• Susceptibility to amoxicillin of oral streptococci [ Time Frame: at day 0, day 9 and day 30. ] [ Designated as safety issue: Yes ]
  

• Non-inferiority of clinical efficacy [ Time Frame: at day 9 ] [ Designated as safety issue: Yes ]
  

Amoxicillin treatment starts the day of the inclusion in the study (day 0). Dentists and participants were blinded to treatment assignment for the duration of the study. The infected tooth was extracted 2 days after the beginning of the antibiotic treatment, and the post-operative follow-up was done 1 week after tooth extraction (day 9). An additional follow-up was done one month later (day 30).

Clinical parameters were collected one week after tooth extraction (day 9). Pain was evaluated by its intensity during the days following surgery (using an analog visual scale varying from 0 -no pain- to 10 -very intense pain-), and by the total amount (in mg) of paracetamol ingested. The infectious state was evaluated by local wound healing, regional adenopathy and fever. The wound healing score combined local inflammation and sensitivity, and the presence or absence of a blood clot.

The streptococci resistance was assessed at the patient-level by the proportion of patient with at least one resistant streptococcus, and at the streptococcus-level by the proportion of resistant streptococcus out of the total streptococci flora. Intermediate susceptibility to amoxicillin was defined as a minimum inhibitory concentration (MIC) of 0.5-16 mg/L; resistance was defined as an MIC greater than or equal to 16 mg/L.