Different antibiotic protocols in the treatment of severe chronic periodontitis: A 1‐year randomized trial

Aim To evaluate the clinical effects of different dosages of metronidazole (MTZ) and durations of MTZ + amoxicillin (AMX) in the treatment of generalized chronic periodontitis (GChP). Material and Methods Subjects with severe GChP were randomly assigned to receive scaling and root planing (SRP)‐only, or combined with 250 or 400 mg of MTZ + AMX (500 mg) thrice a day (TID), for 7 or 14 days. Subjects were monitored for 1 year. Results One hundred and nine subjects were enrolled. At 1 year, 61.9% and 63.6% of the subjects receiving AMX + 250 or 400 mg of MTZ for 14 days, respectively, reached the clinical endpoint for treatment (≤4 sites with probing depth ≥5 mm), against 31.8% of those taking 250 or 400 mg of MTZ for 7 days (p