ABSTRACT
Objective@#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.@*Methods@#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.@*Results@#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. @*Conclusion @#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.
ABSTRACT
Objective@#Metagenomic sequencing was used to explore the species composition and internal functional metabolic pathway of saliva and supragingival plaque microbial communities in healthy adults to provide a theoretical reference for the biological prevention and treatment of oral diseases.@*Methods@#Saliva and supragingival plaque samples were collected from healthy adults, total DNA was extracted, and a metagenomic library was constructed. The qualified library was sequenced via metagenomics, and the sequencing data were analyzed using bioinformatics and statistics. @*Results @#The main bacterial phyla in healthy oral samples were Proteobacteria (32.51%), Bacteroidetes (30.81%), and Actinobacteria (16.23%), and the main bacterial species were Corynebacterium matruchotii (3.84%), Haemophilus parainfluenzae (2.91%), and Prevotella melaninogenica (2.76%). The alpha diversity of the supragingival plaque group was higher than that of the saliva group, and there was a significant difference in the composition of the microbial community between the two groups (P<0.05). At the species level, Prevotella melaninogenica, Fusobacterium periodonticum, and Prevotella intermedia were more abundant in saliva samples than in supragingival plaque samples, while Corynebacterium matruchotii, Propionibacterium acidifaciens, and Rothia dentocariosa were more abundant in supragingival plaque samples than in saliva samples (P<0.05). High-quality gene sets of saliva and supragingival plaque in healthy adults were constructed based on metagenomic sequencing. The results of KEGG pathway functional metabolic differences showed that starch and sucrose metabolism, leucine and isoleucine degradation, and arginine biosynthesis in salivary microorganisms were more abundant than in supragingival plaque, while glycolysis/gluconeogenesis and carbon metabolism in supragingival plaque were more abundant than in saliva.@* Conclusion@#There are significant differences in the species composition and functional gene metabolic pathways of saliva and supragingival plaque microecology in healthy adults. The sensitivity of dominant species in different microecological regions to the identification of oral diseases may be different. In the microbiological study of oral diseases, appropriate samples should be selected according to different diseases.
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Objective To compare oral hygiene practices, education and social background, food intake and oral malodor of Algerian adults suffering from dental caries with normal controls, and to determine and compare the bacterial composition of the supragingival plaques from the above-mentioned groups. Methods Participants completed a questionnaire and were clinically examined for dental caries using decayed, missing and filled teeth index according to the criteria laid down by the World Health Organization. Supragingival plaque samples were collected from 50 caries-free adults (CF) and 50 caries-active adults (CA). Standard procedures of culture and identification of aerobic and anaerobic bacteria were used. Data were analyzed using Chi-square test. Results A total of 117 bacterial strains were isolated from supragingival plaques in CF group subjects, 76 (64.96%) of them belonged to 9 aerobic genera, and 41 (35.04%) to 9 anaerobic genera (P < 0.05). While in the second group, 199 strains were isolated, 119 (59.80%) of the strains belonged to 10 aerobic genera and 80 (40.20%) to 10 anaerobic bacteria (P < 0.05). Streptococcus mutans, Enterococcus faecium, Aerococcus viridans, Actinomyces meyeri, Lactobacillus acidophilus and Eubacterium limosum showed a significantly higher prevalence in the CA group (P < 0.05). The findings revealed that CA group had a high sugar intake (80%). A significantly higher frequency of tooth brushing (P < 0.000) and a significantly less self-reported oral malodor (P < 0.000) and tooth pain (P < 0.000) were found in CF group, while there was no association of socioeconomic levels and intake of meal snacks with dental caries. Conclusions This study confirms the association of some aciduric bacteria with caries formation, and a direct association of sugar intake and cultural level with dental caries. Furthermore, oral hygiene practices minimize the prevalence of tooth decay.
ABSTRACT
Objective: To compare oral hygiene practices, education and social background, food intake and oral malodor of Algerian adults suffering from dental caries with normal controls, and to determine and compare the bacterial composition of the supragingival plaques from the above-mentioned groups. Methods: Participants completed a questionnaire and were clinically examined for dental caries using decayed, missing and filled teeth index according to the criteria laid down by the World Health Organization. Supragingival plaque samples were collected from 50 caries-free adults (CF) and 50 caries-active adults (CA). Standard procedures of culture and identification of aerobic and anaerobic bacteria were used. Data were analyzed using Chi-square test. Results: A total of 117 bacterial strains were isolated from supragingival plaques in CF group subjects, 76 (64.96%) of them belonged to 9 aerobic genera, and 41 (35.04%) to 9 anaerobic genera (P<0.05). While in the second group, 199 strains were isolated, 119 (59.80%) of the strains belonged to 10 aerobic genera and 80 (40.20%) to 10 anaerobic bacteria (P<0.05). Streptococcus mutans, Enterococcus faecium, Aerococcus viridans, Actinomyces meyeri, Lactobacillus acidophilus and Eubacterium limosum showed a significantly higher prevalence in the CA group (P<0.05). The findings revealed that CA group had a high sugar intake (80%). A significantly higher frequency of tooth brushing (P<0.000) and a significantly less self-reported oral malodor (P<0.000) and tooth pain (P<0.000) were found in CF group, while there was no association of socioeconomic levels and intake of meal snacks with dental caries. Conclusions: This study confirms the association of some aciduric bacteria with caries formation, and a direct association of sugar intake and cultural level with dental caries. Furthermore, oral hygiene practices minimize the prevalence of tooth decay.