The purpose of this study is to examine if the correct use of antibiotics, as well as the
application of one-day-treatment, in the therapy of periodontal diseases. The population of
treated patients (184) are divided in 4 groups; Group 1: Metronidazole + mechanical treatment
in one day, Group 2: Placebo + mechanical treatment in one day Group 3: Metronidazole +
mechanical treatment on day 1 and 21 Group 4: Placebo + mechanical treatment on day 1 and 21
End points, BOP, Plaque, PPD, CAL, RAL, Microbiology will be recorded on all sites at 3
months, 1 -, 3 -, and 5 years post-treatment