Distribution and function of cariogenic bacteria in supragingival plaque in patients with type 2 diabetes mellitus

To investigate the distribution characteristics and functional genes of cariogenic bacteria in oral microorganisms of patients with type 2 diabetes mellitus and to improve the understanding of the relationship between type 2 diabetes mellitus and dental caries.

The experimental group included 10 patients with type 2 diabetes treated in the Department of Endocrinology, the First Affiliated Hospital of Air Force Medical University. The normal control group included healthy oral subjects without type 2 diabetes in the community population (10 cases). Samples of supragingival plaque from patients with type 2 diabetes mellitus and normal controls were collected and sequenced. Bioinformatics and statistical analysis of cariogenic bacteria such as Streptococcus mutans, Lactobacillus, Actinomyces viscosus and Candida albicans were carried out.

There were slightly fewer cariogenic bacteria such as Streptococcus mutans, Lactobacillus, Actinomyces viscosus and Candida albicans in supragingival plaque samples of type 2 diabetic patients than in normal controls, but the difference was not statistically significant (P＞0.05). The results of KEGG pathway functional metabolic differences showed that the metabolic pathways of D-arginine and D-ornithine metabolism, biofilm formation-Escherichia coli, carolactam degradation and arginine biosynthesis were more abundant in the T2DM group than in the normal control group, while metabolic pathways such as tyrosine metabolism, selenocompound metabolism and pyruvate metabolism showed the opposite trend.

There was no significant difference in the content of cariogenic microorganisms between type 2 diabetic patients and normal control group. The differential metabolic pathways of the functional genes indicated that an increase in the arginine metabolic pathway was beneficial to the maintenance of acid-base balance in the oral microecological environment.