The Qualitative and Quantitative Structure of Oral Microbiocenosis in Rats with Periodontitis in a Setting of Hyper- and Hypothyroidism

Abstract

Background and aims. Oral microbial flora is a highly sensitive indicator system producing qualitative and quantitative responses to changes in various individual organs and systems. The aim of study was to perform a comparative analysis of qualitative and quantitative structure of oral microbiocenosis in rats with comorbidity-free periodontitis and in animals with periodontitis in a setting of hyper- and hypothyroidism. Material and methods. Experimental studies were conducted on 48 mature male white rats. Samples for microbiological tests were taken from dental surfaces (on the border between hard tissue and gums in the interdental spaces). The isolated pure cultures were identified by their morphological, tinctorial, cultural and biochemical properties and the signs of pathogenecity. Results. We found that the oral dysbiosis occurring in a setting of periodontitis in rats is chiefly characterized by increased quantity of coccal forms and by increased candidal inoculation; these organisms cumulatively inhibit the growth of normal microbial flora, such as Lactobacilli, bacteroids and Bifidobacteria. Thyroid dysfunction exacerbates changes in the qualitative and quantitative structure of oral microbiocenosis. Conclusions. The periodontitis in a setting of thyroid dysfunction increases both the species variety and the quantitative counts of oral microbial flora, with predominance of such microbial organisms as Staph. aureus, E. coli, E. faecalis, Candida albicans and P. aeruginosa.