 After controlling for normal distribution CAL-V gain and PD reduction for the 2 test groups DOXYPLAC are compared using an independent t test. Intragroup comparisons baseline1224 months are calculated using the paired t test. Inter and intragroup comparisons for radiographic bone, PI and GI are calculated using Mann Whitney U and Wilcoxon test, respectively. To explore the impact of subgingival microflora on the primary and secondary outcome variables we compare CAL-V gain independent t test 6 months and bony fill Mann Whitney U 12 months after therapy according to presenceabsence of the tested periodontal pathogens. 