Influence of oral hygiene in patients with fixed appliances in the oral carriage of antimicrobial-resistant Escherichia coli and Enterococcus isolates

Changes in oral health during aging in a novel non-human primate model

Oral health plays a significant role in the quality of life and overall well-being of the aging population. However, age-related changes in oral health are not well understood due to challenges with current animal models. In this study, we analyzed the oral health and microbiota of a short-lived non-human primate (i.e., marmoset), as a step towards establishing a surrogate for studying the changes that occur in oral health during human aging. We investigated the oral health of marmosets using cadaveric tissues in three different cohorts: young (aged ≤6 years), middle-aged, and older (>10 years) and assessed the gingival bacterial community using analyses of the V3-V4 variable region of 16S rRNA gene. The oldest cohort had a significantly higher number of dental caries, increased dental attrition/erosion, and deeper periodontal pocket depth scores. Oral microbiome analyses showed that older marmosets had a significantly greater abundance of Escherichia-Shigella and Propionibacterium, and a lower abundance of Agrobacterium/Rhizobium at the genus level. Alpha diversity of the microbiome between the three groups showed no significant differences; however, principal coordinate analysis and non-metric multidimensional scaling analysis revealed that samples from middle-aged and older marmosets were more closely clustered than the youngest cohort. In addition, linear discriminant analysis effect size (LEFSe) identified a higher abundance of Esherichia-Shigella as a potential pathogenic biomarker in older animals. Our findings confirm that changes in the oral microbiome are associated with a decline in oral health in aging marmosets. The current study suggests that the marmoset model recapitulates some of the changes in oral health associated with human aging and may provide opportunities for developing new preventive strategies or interventions which target these disease conditions.

The effect of the addition of propolis to resin-modified glass ionomer cement bracket adhesive materials on the growth inhibition zone of Streptococcus mutans

Background: Orthodontic treatments progress alongside the development of adhesive materials. The present study aimed to determine the antibacterial properties of propolis, a natural product, in a mixture of resin-modified glass ionomer cement by observing the growth inhibition zone of  Streptococcus mutans.Methods: This was an in vitro study conducted on 45 samples of adhesive material, which were divided into control group (resin-modified glass ionomer cement bracket adhesive material), two groups of propolis concentrations (15%, and 25%) and duration (0, 15, and 30 days). The antibacterial effect of each sample was evaluated against S. mutans using an agar plate diffusion test. Measurement of the diameter of the growth inhibition zone of S. mutans was carried out. The data obtained were analyzed statisticallyThe significance value of the Kruskal Wallis and Mann-Whitney test was set at p <0.05, while the significance value of the normality and homogeneity test was set at p> 0.05). Datas in this study that were not normally distributed (p = 0.012) but homogeneous (p = 0.110) were analyzed by the Kruskal-Wallis test (p = 0.003) and then the Mann-Whitney test was performed to determine differences in significance between groups. Results: There was a relationship between concentration and duration of propolis to the growth inhibition zone of S. mutans (p=0.003). The addition of 25% propolis concentration inhibited the growth of S. mutans more than the addition of 15% and without propolis (control group). The addition of propolis to resin-modified glass ionomer cement for 15 days was more effective in inhibiting the growth of S. mutans.Conclusion: The addition of propolis to adhesive materials provides an inhibitory effect on the growth of S. mutans, which may be effective in the world of preventive dentistry.

The effect of the addition of propolis to resin modified glass ionomer cement bracket adhesive materials on the growth inhibition zone of Streptococcus mutans

Background: Orthodontic treatments progress alongside the development of adhesive materials. The aim of the present study was to determine the antibacterial properties of propolis, a natural product, in a mixture of resin modified glass ionomer cement by observing the growth inhibition zone of Streptococcus mutans. Methods: This was an in vitro study conducted on 45 samples of adhesive material, which were divided into three groups of propolis concentrations (0%, 15%, and 25%) and duration (0, 15, and 30 days). The antibacterial effect of each sample was evaluated against S. mutans using an agar plate diffusion test. Measurement of the diameter of the growth inhibition zone of S. mutans were carried out. The data obtained were analyzed statistically by Kruskal Wallis test. Results: There was a relationship between concentration and duration of propolis to the growth inhibition zone of S. mutans (p<0.05). The addition of 25% propolis concentration inhibited the growth of S. mutans more than the addition of 15% and 0% propolis concentration. The addition of 0%, 15%, and 25% propolis concentration to resin modified glass ionomer cement for 15 days was more effective in inhibiting the growth of S. mutans.Conclusion: The addition of propolis to adhesive materials provides an inhibitory effect on the growth of S. mutans, which may be effective in the world of preventive dentistry.

Preliminary studies on the inhibition potential of Indian domestic curd against coliforms, an emerging periodontal pathogen

Background:

Coliforms colonize in dental plaques via oral route and may lead to systemic complications. Escherichia coli and its lipopolysaccharide-induced periodontitis is an emerging threat. Clinical management necessitates antibiotic regimens with risk of resistance and upsetting the gut. There is urgent need for better, sustainable, and economical alternative.

Aim:

To investigate the inhibition of coliforms, a potential periodontopathogen directly by Indian domestic curd (IDC) “in situ".

Materials and Methods:

Coliforms from natural habitat (Municipal sewage in Agartala, Tripura), a source of infection through food and water, were used as target organism. Domestically prepared curd without any fortification is used to explore its true inhibition potential. Assays of agar well diffusion performed with IDC (ultraviolet sterilized and pH adjusted 6.5) against isolated pure cultures of coliforms. The study protocol nullified effect of organic acids, volatile compounds, bacteriophages, and peroxides in IDC. Peptide nature of inhibitory ingredient was studied by Sodium Dodecyle Sulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE), urea treatment. Computational phylogenetics revealed structural features of inhibitory ingredient. Statistical comparisons were done by analysis of variance. Second-order polynomial regression was done to evaluate the effect of IDC dilution on coliform inhibition. Mann–Whitney U-test performed to analyze different sample treatments.

Results:

Agar well diffusion (sealed bottom wells) shows inhibition of catalase-negative coliforms (confirmed by Gram staining and triple sugar iron agar assay) in pure culture (MacConkey agar). Activity diminished in urea, potentiated in ethylene diamine tetra acetic acid, remains unchanged by heat treatment (121°C, 15 min). SDS-PAGE revealed three distinct peptides (>10–15KDa). Hence, thermostable inhibitory peptides attached to target cell lead to observed activity (titer up to 1204.82 AU/ml with minimum 8 mm inhibition).

Conclusions:

IDC adequately inhibits sewage coliforms and may prevent dental plaques coliform colonization and its associated risks.

A Decade-Long Commitment to Antimicrobial Resistance Surveillance in Portugal

Antimicrobial resistance (AMR) is a worldwide problem with serious health and economic repercussions. Since the 1940s, underuse, overuse, and misuse of antibiotics have had a significant environmental downside. Large amounts of antibiotics not fully metabolized after use in human and veterinary medicine, and other applications, are annually released into the environment. The result has been the development and dissemination of antibiotic-resistant bacteria due to many years of selective pressure. Surveillance of AMR provides important information that helps in monitoring and understanding how resistance mechanisms develop and disseminate within different environments. Surveillance data is needed to inform clinical therapy decisions, to guide policy proposals, and to assess the impact of action plans to fight AMR. The Functional Genomics and Proteomics Unit, based at the University of Trás-os-Montes and Alto Douro in Vila Real, Portugal, has recently completed 10 years of research surveying AMR in bacteria, mainly commensal indicator bacteria such as enterococci and Escherichia coli from the microbiota of different animals. Samples from more than 75 different sources have been accessed, from humans to food-producing animals, pets, and wild animals. The typical microbiological workflow involved phenotypic studies followed by molecular approaches. Throughout the decade, 4,017 samples were collected and over 5,000 bacterial isolates obtained. High levels of AMR to several antimicrobial classes have been reported, including to β-lactams, glycopeptides, tetracyclines, aminoglycosides, sulphonamides, and quinolones. Multi-resistant strains, some relevant to human and veterinary medicine like extended-spectrum β-lactamase-producing E. coli and vancomycin-resistant enterococci, have been repeatedly isolated even in non-synanthropic animal species. Of particular relevance are reports of AMR bacteria in wildlife from natural reserves and endangered species. Future work awaits as this threatening yet unsolved problem persists. GRAPHICAL ABSTRACTSummary diagram of the antimicrobial resistance surveillance work developed by the UTAD Functional Genomics and Proteomics Unit.

Effects of Fixed and Removable Space Maintainers on Plaque Accumulation, Periodontal Health, Candidal and Enterococcus Faecalis Carriage

OBJECTIVE

To evaluate the effects of space maintainers on plaque accumulation, periodontal health and oral microflora.

SUBJECTS AND METHODS

The study participants comprised 38 patients aged 4-10 years requiring either fixed or removable space maintainers. Plaque index, gingival index, bleeding on probing index, candidal colonization and Enterococcus faecalis were recorded just before the application of space maintainers (T0) and during treatment at the 1st (T1), 3rd (T2) and 6th (T3) month.

RESULTS

The gingival and bleeding on probing index scores increased significantly (gingival index from 0.20 ± 0254 to 0.54 ± 0417 and bleeding on probing index from 7.18 ± 9.946 to 18.07 ± 14.074) in the regions with fixed space maintainers at T3 (p < 0.01). The mean Candida counts also increased (for removable appliances from 1.90 ± 3.638 to 1.98 ± 3.318, p < 0.05, and for fixed appliances from 4.25 ± 4.587 to 4.52 ± 4.431, p < 0.001). The salivary E. faecalis counts at T3 also increased significantly with the use of fixed and removable appliances (for removable appliances from 5.93 ± 2.65 to 85.53 ± 34.1 and for fixed appliances from 4.95 ± 2.94 to 123.59 ± 29.51, p < 0.001). A positive correlation was found between the plaque (r = 0.67), gingival (r = 0.76) and bleeding on probing index scores (r = 0.76) and the candidal colonization for the fixed space maintainers (p < 0.01, p < 0.001).

CONCLUSIONS

In this study, both fixed and removable space maintainers led to an increase in the number of microorganisms in the oral cavity as well as to increases in the periodontal index scores. Patients should be informed that space maintainers may serve as a source of infection and that special attention must be given to their oral hygiene.

Antibacterial and mechanical properties of propolis added to glass ionomer cement

OBJECTIVE

To investigate whether adding ethanolic extracts of propolis (EEP) might influence the antibacterial and mechanical (shear-peel band strength [SPBS]) properties of conventional glass ionomer cement (GIC) used in orthodontic band cementation.

MATERIALS AND METHODS

The cement was divided into four groups: one using the original composition and three with 10%, 25%, and 50% EEP added to the liquid and then manipulated. An antimicrobial assay, broth-dilution method was used to determine the antibacterial capacity of the GIC containing EEP. Eighty teeth were used for the mechanical assay, and an Instron testing machine was used to evaluate the SPBS. Kolmogorov-Smirnov and Kruskal-Wallis tests were used for statistical analyses.

RESULTS

GIC with the addition of 25% and 50% EEP activated inhibition of Streptococcus mutans (ATCC 25175) growth, but this effect did not occur in the group to which 10% EEP was added or in the control GIC group. There was no significant difference between the groups in terms of SPBS (P > .05).

CONCLUSIONS

The addition of EEP may increase antibacterial properties without negatively modifying the mechanical properties of conventional GIC.

Oral carriage of enterobacteriaceae among school children with chronic nail-biting habit

Context:

Onychophagia or habitual nail-biting is widespread among children and adolescents, between 10 and 18 years. Prevalence estimates range from 30% during childhood to 45% in adolescence. Nail-biting habit can result in autoinoculation of pathogens and transmission of infection between body parts.

Aims:

The purpose of the study was to evaluate the differences in prevalence of Enterobacteriaceae (E. coli and Enterobacter spp) in saliva samples from subjects with and without chronic nail-biting habit.

Subjects and Methods:

One hundred and twenty-two subjects with chronic nail-biting habit and 122 subjects with no oral habit were enrolled in the study. All subjects were aged 11-15 years. The saliva samples were collected by oral rinse technique, samples were studied microbiologically.

Statistical Analysis Used:

Two-tailed Student's t-test and Chi-square/Fisher's exact test were used to find the significance of study parameters between the groups.

Results:

Enterobacteriaceae were detected in the saliva samples of 80 of the 122 nail-biting subjects, whereas Enterobacteriaceae were detected in the saliva samples of only 10 of the 122 subjects who were not nail-biters. This difference in prevalence was statistically significant (P < 0.001).

Conclusions:

Our results suggest a higher carriage of Enterobacteriaceae in the individuals having nail-biting habits when compared to individuals with no habits. Further studies need to be done to know the prevalence of Enterobacteriaceae species in different age groups.

A novel and potentially valuable exposure measure: Escherichia coli in oral cavity and its association with child daycare center attendance

This study investigated the occurrence of Escherichia coli, an indicator of fecal contamination, in saliva samples from 141 children up to 36 months old, 53 not attending and 88 attending a child daycare center after exposure to a public daycare center and home environments. Two samples from each child were collected on the same day at 07:00 and 15:00 h and plated on MacConkey agar for identification. Samples E. coli negative in the morning and positive in the afternoon were statistically associated with the condition of the child attending daycare center (Odds ratio = 2.72; 95% confidence interval = 1.15/6.46). Exposure to the daycare center environment favored the potential risk of transmission of enteropathogens, as demonstrated by the presence of E. coli in saliva. The method proved to be easy to sample, non-invasive and feasible in young children. The findings suggest a novel and potentially valuable exposure measure.