Eickholz P, et al. - In this explorative per-protocol collective analysis, researchers analyzed the 345 candidates to assess the influence of systemic amoxicillin/metronidazole in the improvement of periodontitis. Individuals (N=170) were given systemic amoxicillin 500 mg/metronidazole 400 mg (3x/day, 7 days) and placebo to 175 cases for 3 months. They, then, calculated the treatment effect ie, % of sites with new attachment loss ≥ 1.3 mm at 27.5 months after treatment. With adjunctive antimicrobials, they found a reduction in median new attachment loss in individuals < 55 years of age (5.2%), or with ≥ 35% pocket probing depth (PPD) ≥ 5 mm (4.5%), or with a mean attachment level > 5 mm (5.2%) at baseline when compared to the placebo (9.0%, 11.6%, and 12.5%, respectively). Hence, they concluded a dependence of clinical benefits of systemic amoxicillin/metronidazole on the severity of periodontitis and age of the subject.