Clinical and microbiological assessment in a subpopulation of young Argentine patients with severe periodontitis

Aggressive periodontitis (AP) is the most serious entity of periodontal disease (stage III/IV, grade C periodontitis according to the latest classification, 2017). Aim: to enhance knowledge of periodontal microbiota in AP in native Argentine patients and describe the effect of a combined pharmacological-mechanicalperiodontal treatment on clinical and microbiological parameters. Materials andMethod: The study analyzed 42 periodontal sites in 11 patients diagnosed with AP. Clinical periodontal parameters were recorded at baseline, 45, 90 and 180 days. Microbiological samples were taken before treatment and at 180 days. PCR was used to determine presence of the periodontopathic bacteria Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf), Treponema denticola (Td), Prevotella intermedia (Pi) and Fusobacterium nucleatum (Fn). Patients underwent periodontal therapy including antibiotics (Amoxicillin 500mg + Metronidazole 250mg; 8hs/7 days), and were reevaluated at 45, 90 and 180 days. Results: Mean age was 28.4 ± 7.9 years. The initial PCR detected the following frequencies: Aa 14.3%, Pi 61.9%, Pg 71.4%, Tf 81.0%, Fn 95.2% and Td 97.6%. Baseline microbiological samples revealed significantly higher prevalence of Pg over Aa (p=0.012). Clinical parameters improved significantly after treatment (73.8% PS<5 mm; PS, NIC, SS p<0.001). At 180 days, a significant decrease in microbiological detection rates was observed (Fn, Td, Tf, Pi, Aa p<0.05). Aa was no longer detectable while Pg did not decrease significantly (p=0.052). Fn was the only study species detected in 100% (n=11:42) of residual pockets (PS>5 mm) (p=0.053). Conclusion: In the initial samples, there was significant prevalence of Pg over Aa. Significant clinical improvement was achieved after the mechanical-pharmacological treatment, with undetectable levels ofAa, while Fn persisted in residual pockets, and Pg was present at most of the treated sites.