28 PP
MICROBIOLOGY OF SUBGINGIVAL PLAQUES IN ARGENTINEAN ADULT PERIODONTITIS

Fernández Canigia L ¹*, Nogueira Moreira A², Furman C^1,3, Piovano S³, Bianchini Hsup1. 1- Centro de Educacion e Investigaciones Clinicas (CEMIC); 2- Facultad de Odontologia, UBA; 3- Facultad de Odontologia de la Universidad Maimonides. Buenos Aires, Argentina.

We report the microbiological features of subgingival plaques from 45 patients (range 30-65 years) with adult periodontitis. Thus, 138 sites displaying disease of periodontitis were assessed. Samples from subgingival plaque were collected by inserting two paper point into the periodontal pocket and were stored in VMGIII medium until used. They were cultured onto Chocolate agar, K vitamin-supplemented Brucella agar with and without amikacin and colistin and a selective medium (TSBV) for Actinobacillus actinomycetemcomitans. Dark field examination was also performed in order to estimate the relative frequency of different morphotypes. All samples were processed within the 60 min after collection. Plates were incubated in both anaerobic and 10% CO₂ atmospheres for 14 days. Pigmented anaerobic rods were identified by 4- metilumbeliferil substrates. Significant differences in motile organisms were observed between healthy and sick sites (19% versus 73%, respectively, p < 0.01). Prevotella intermedia, Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis were frequently isolated (80%, 47% and 20%, respectively) from the sick sites, while they were not found in healthy sites. Microbiological assecment of adult periodontitis may be of interest for the management and understanding of this complex pathology.