-
PloS One 2017Dental caries is the most prevalent disease in humans globally. Efforts to control it have been invigorated by an increasing knowledge of the oral microbiome...
Dental caries is the most prevalent disease in humans globally. Efforts to control it have been invigorated by an increasing knowledge of the oral microbiome composition. This study aimed to evaluate the bacterial diversity in occlusal biofilms and its relationship with clinical surface diagnosis and dietary habits. Anamneses were recorded from thirteen 12-year-old children. Biofilm samples collected from occlusal surfaces of 46 permanent second molars were analyzed by 16S rRNA amplicon sequencing combined with the BLASTN-based search algorithm for species identification. The overall mean decayed, missing and filled surfaces modified index [DMFSm Index, including active white spot lesions (AWSL)] value was 8.77±7.47. Biofilm communities were highly polymicrobial collectively, representing 10 bacterial phyla, 25 classes, 29 orders, 58 families, 107 genera, 723 species. Streptococcus sp_Oral_Taxon_065, Corynebacterium matruchotii, Actinomyces viscosus, Actinomyces sp_Oral_Taxon_175, Actinomyces sp_Oral_Taxon_178, Actinomyces sp_Oral_Taxon_877, Prevotella nigrescens, Dialister micraerophilus, Eubacterium_XI G 1 infirmum were more abundant among surfaces with AWSL, and Streptococcus gordonii, Streptococcus sp._Oral_Taxon_058, Enterobacter sp._str._638 Streptococcus australis, Yersinia mollaretii, Enterobacter cloacae, Streptococcus sp._Oral_Taxon_71, Streptococcus sp._Oral_Taxon_F11, Centipeda sp._Oral_Taxon_D18 were more abundant among sound surfaces. Streptococcus mutans was detected on all surfaces in all patients, while Streptococcus sobrinus was detected only in three patients (mean relative abundances 7.1% and 0.6%, respectively). Neither species differentiated healthy from diseased sites. Diets of nine of the subjects were scored as high in fermentable carbohydrates (≧2X/day between meals). A direct association between relative abundances of bacteria and carbohydrate consumption was observed among 18 species. High consumption of fermentable carbohydrates and sound surfaces were associated with a reduction in bacterial diversity. PCoA plots displayed differences in bacterial community profiles between sound and diseased surfaces. Our study showed that, in addition to mutans streptococci, other species may be associated with the initiation of dental caries on occlusal surfaces, and that biofilm diversity of tooth surfaces is influenced by carbohydrate consumption and a surface's health status.
Topics: Bacteria; Brazil; Child; Cross-Sectional Studies; Dental Caries; Diet; Female; Humans; Male; Microbiota; Mouth; Surface Properties
PubMed: 28678838
DOI: 10.1371/journal.pone.0180621 -
International Journal of Dentistry 2022The application of herbal and/or chemical antimicrobial mouthwashes in addition to the mechanical methods of bacteria removal helps reduce the periopathogens and thus...
BACKGROUND
The application of herbal and/or chemical antimicrobial mouthwashes in addition to the mechanical methods of bacteria removal helps reduce the periopathogens and thus increase the periodontal tissues' health. The present study aimed to evaluate the antibacterial effect of Thymex (TMX) syrup on three periodontal facultative anaerobes in vitro and compare it with 0.2% chlorhexidine (CHX) mouthwash.
METHODS
In this in vitro experiment, the disc diffusion method was used to measure the inhibitory halo diameter (IhD) of , , and . The paper discs containing TMX and CHX were placed on Mueller-Hinton agar media and cultured with the mentioned bacteria. Moreover, a blank disc containing distilled water was used as a control. From each of the three bacterial species, five samples were taken, and after 18 hours of storage in the incubator, the IhDs were measured in millimeters. A one-way ANOVA test and an independent sample -test were used to compare the mean differences of IhDs between groups. The significance level was considered to be 0.05.
RESULTS
The IhDs ranged between 6.2-8.8 mm and 12.3-34 mm for TMX and CHX, respectively. CHX showed a more inhibitory effect on all three species of bacteria compared to TMX mouthwash ( < 0.001).
CONCLUSIONS
Despite the inhibitory effect of TMX on bacterial growth, CHX showed significantly more antibacterial activity than TMX against three studied bacterial species.
PubMed: 36620479
DOI: 10.1155/2022/6359841 -
Microbiology Spectrum Apr 2024Antimicrobial resistance is one of the greatest challenges to global health. While the development of new antimicrobials can combat resistance, low profitability reduces...
Antimicrobial resistance is one of the greatest challenges to global health. While the development of new antimicrobials can combat resistance, low profitability reduces the number of new compounds brought to market. Elucidating the mechanism of action is crucial for developing new antimicrobials. This can become expensive as there are no universally applicable pipelines. Phenotypic heterogeneity of microbial populations resulting from antimicrobial treatment can be captured through flow cytometric fingerprinting. Since antimicrobials are classified into limited groups, the mechanism of action of known compounds can be used for predictive modeling. We demonstrate a cost-effective flow cytometry approach for determining the mechanism of action of new compounds. Cultures of and were treated with different antimicrobials and measured by flow cytometry. A Gaussian mixture mask was applied over the data to construct phenotypic fingerprints. Fingerprints were used to assess statistical differences between mechanism of action groups and to train random forest classifiers. Classifiers were then used to predict the mechanism of action of cephalothin. Statistical differences were found among the different mechanisms of action groups. Pairwise comparison showed statistical differences for 35 out of 45 pairs for and for 32 out of 45 pairs for after 3.5 h of treatment. The best-performing random forest classifier yielded a Matthews correlation coefficient of 0.92 and the mechanism of action of cephalothin could be successfully predicted. These findings suggest that flow cytometry can be a cheap and fast alternative for determining the mechanism of action of new antimicrobials.IMPORTANCEIn the context of the emerging threat of antimicrobial resistance, the development of novel antimicrobials is a commonly employed strategy to combat resistance. Elucidating the mechanism of action of novel compounds is crucial in this development but can become expensive, as no universally applicable pipelines currently exist. We present a novel flow cytometry-based approach capable of determining the mechanism of action swiftly and cost-effectively. The workflow aims to accelerate drug discovery and could help facilitate a more targeted approach for antimicrobial treatment of patients.
Topics: Humans; Cephalothin; Flow Cytometry; Cost-Benefit Analysis; Anti-Infective Agents; Drug Development; Anti-Bacterial Agents
PubMed: 38483479
DOI: 10.1128/spectrum.03931-23 -
Journal of Ayurveda and Integrative... 2020Dental caries is a biofilm-related infectious disease with a multifactorial etiology, over five billion inhabitants have affected worldwide due to this disease.
BACKGROUND
Dental caries is a biofilm-related infectious disease with a multifactorial etiology, over five billion inhabitants have affected worldwide due to this disease.
OBJECTIVE
Antimicrobial efficacy of a mixed herbal powder extract (MHPE) against cariogenic microorganisms was investigated.
MATERIALS AND METHODS
MIC, MBC, kinetics of killing, biofilm disruption and anticaries effect of MHPE were determined. For biofilm disruption, biofilms of Streptococcus mutans, Lactobacillus casei, Actinomyces viscosus and Candida albicans were treated with MHPE for 30 min and attached cells were quantified after staining. For live/dead staining biofilm assay, S. mutans biofilm treated with MHPE for 1min, 5min and 1 h was examined with confocal laser scanning system after live/dead staining. Efficacy was experimented by structural quality using Scanning Electron Microscope (SEM). Anticaries effect was determined by formation of caries-like lesion in continuous flow biofilm model.
RESULTS
MHPE exhibited inhibition zones ranging from 12.5 to 24.0 mm. The highest inhibition zone was recorded at concentration of 50 μg/ml. MIC for S. mutans was between 12.23 and 36.7 μg/ml, while the MBC values ranged from 36.7 to 110.65 μg/ml. Inhibitory concentration of MHPE was three fold higher than CHLX. Significant reduction of cell count (49-95%) was observed with increasing time and higher concentration. Percentage biofilm reduction compare with negative control was 96.9% (A. viscosus), 94% (C. albicans), 99.8% (L. casei) and 91.7% (S. mutans). For MHPE-treated biofilm, live/dead staining demonstrated significant (p < 0.05) higher in deceased red fluorescence areas in all kinetics points from 53.6% (1min) to 85% (1h). SEM confirmed the damage in the outer layers of S. mutans. MHPE has components with effective antibacterial activity against caries-inducing microorganisms.
CONCLUSION
The anti-adherence and anti-biofilm effect as well as the faster killing activity suggests that MHPE formula has effective antibacterial activity and could be a useful source of anti-cariogenic agents in near future.
PubMed: 30389224
DOI: 10.1016/j.jaim.2018.01.005 -
Frontiers in Microbiology 2016In oral health, the interdental spaces are a real ecological niche for which the body has few or no alternative defenses and where the traditional daily methods for...
In oral health, the interdental spaces are a real ecological niche for which the body has few or no alternative defenses and where the traditional daily methods for control by disrupting biofilm are not adequate. The interdental spaces are the source of many hypotheses regarding their potential associations with and/or causes of cardiovascular disease, diabetes, chronic kidney disease, degenerative disease, and depression. This PCR study is the first to describe the interdental microbiota in healthy adults aged 18-35 years-old with reference to the Socransky complexes. The complexes tended to reflect microbial succession events in developing dental biofilms. Early colonizers included members of the yellow, green, and purple complexes. The orange complex bacteria generally appear after the early colonizers and include many putative periodontal pathogens, such as Fusobacterium nucleatum. The red complex (Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola) was considered the climax community and is on the list of putative periodontal pathogens. The 19 major periodontal pathogens tested were expressed at various levels. F. nucleatum was the most abundant species, and the least abundant were Actinomyces viscosus, P. gingivalis, and Aggregatibacter actinomycetemcomitans. The genome counts for Eikenella corrodens, Campylobacter concisus, Campylobacter rectus, T. denticola, and Tannerella forsythensis increased significantly with subject age. The study highlights the observation that bacteria from the yellow complex (Streptococcus spp., S. mitis), the green complex (E. corrodens, Campylobacter gracilis, Capnocytophaga ochracea, Capnocytophaga sputigena, A. actinomycetemcomitans), the purple complex (Veillonella parvula, Actinomyces odontolyticus) and the blue complex (A. viscosus) are correlated. Concerning the orange complex, F. nucleatum is the most abundant species in interdental biofilm. The red complex, which is recognized as the most important pathogen in adult periodontal disease, represents 8.08% of the 19 bacteria analyzed. P. gingivalis was detected in 19% of healthy subjects and represents 0.02% of the interdental biofilm. T. forsythensis and T. denticola (0.02 and 0.04% of the interdental biofilm) were detected in 93 and 49% of healthy subjects, respectively. The effective presence of periodontal pathogens is a strong indicator of the need to develop new methods for disrupting interdental biofilm in daily oral hygiene.
PubMed: 27313576
DOI: 10.3389/fmicb.2016.00840 -
Journal of Clinical and Diagnostic... Apr 2015To determine and compare the antimicrobial efficacy of ten commercially available herbal dentifrices against specific strains of oral microflora using a standard...
AIM
To determine and compare the antimicrobial efficacy of ten commercially available herbal dentifrices against specific strains of oral microflora using a standard diffusion method at full strength and 1:1 dilution at 24 h.
MATERIALS AND METHODS
The standard strains of Streptococcus. mutans (ATCC 21293), Streptococcus sangius (MTCC 442), Actinomyces viscosus (ATCC 3268), Staphylococcus aureus (ATCC 2592), Streptococcus pyogenes (MTCC 442) and Candida albicans (ATCC 183) were obtained. Antimicrobial efficacy of the dentifrices was tested in triplicate, at full strength and 1:1 dilution with the sterile water using a standard diffusion method for 24 h at 37°C. The antimicrobial efficacy was tested by observing the zones of inhibition in millimeters surrounding disk containing the dentifrice. Mean standard deviation and standard error of mean of the inhibitory zones was calculated for each herbal dentifrice. p<0.05 was considered statistically significant.
RESULTS
Danth Kanthi (DK) was the most effective against all the microorganisms producing larger zones of inhibition at 24 h (F.S - 40±1.5; 1:1 dilution - 40±2.71). Amar Premium (AP) also produced larger zones of inhibition against all microorganisms except S. aureus. Of all the dentifrices, least zones of inhibitions i.e., around 5 mm was observed against S. aureus by Amar Premium (AP) and Dabur Babool (DB) at 24 h.
CONCLUSION
Based on the results of the present study, it can be concluded that all herbal dentifrices exhibited antimicrobial activity against the selected oral microorganisms, with DK being the most effective. Hence, it can be inferred that herbal dentifrices can also be recommended like the conventional formulations.
PubMed: 26023642
DOI: 10.7860/JCDR/2015/11127.5829 -
Infection and Immunity Oct 2022Root caries in geriatric patients is a growing problem as more people are maintaining their natural teeth into advanced age. We determined the levels of various...
Root caries in geriatric patients is a growing problem as more people are maintaining their natural teeth into advanced age. We determined the levels of various bacterial species previously implicated in root caries disease or health using quantitative real-time PCR in a pilot study of 7 patients with 1 to 4 root caries lesions per person. Levels of 12 different species on diseased roots compared to healthy (contralateral control) roots were measured. Four species were found at significantly higher levels on diseased roots (Streptococcus mutans, Veillonella parvula/dispar, Actinomyces naeslundii/viscosus, and Capnocytophaga granulosa) compared across all plaque samples. The level of colonization by these species varied dramatically (up to 1,000-fold) between patients, indicating different patients have different bacteria contributing to root caries disease. Neither of the two species previously reported to correlate with healthy roots (C. granulosa and Delftia acidovorans) showed statistically significant protective roles in our population, although D. acidovorans showed a trend toward higher levels on healthy teeth (0.08). There was a significant positive correlation between higher levels of S. mutans and V. parvula/dispar on the same diseased teeth. mixed biofilm studies demonstrated that co-culturing S. mutans and V. parvula leads to a 50 to 150% increase in sucrose-dependent biofilm mass compared to S. mutans alone, depending on the growth conditions, while V. parvula alone did not form biofilms. The presence of V. parvula also decreased the acidification of S. mutans biofilms when grown in artificial saliva and enhanced the health of mixed biofilms.
Topics: Humans; Aged; Streptococcus mutans; Root Caries; Saliva, Artificial; Pilot Projects; Veillonella; Biofilms; Sucrose; Dental Caries
PubMed: 36129298
DOI: 10.1128/iai.00355-22 -
Brazilian Oral Research Nov 2016The aim of this study was to assess the in vitro antimicrobial effects of chlorhexidine digluconate (CHX), polyhexamethylene biguanide (PHBM), and octenidine...
The aim of this study was to assess the in vitro antimicrobial effects of chlorhexidine digluconate (CHX), polyhexamethylene biguanide (PHBM), and octenidine dihydrochloride (OCT) on cariogenic microorganisms by using their minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). CHX, PHBM, and OCT were diluted in distilled water to the final test concentrations. Using the in-tube dilution method, Streptococcus mutans, Lactobacillus acidophilus, Lactobacillus rhamnosus, and Actinomyces viscosus were cultivated on blood agar and Mueller-Hinton broth (MHB) at 37°C for 48 h. They were read using a spectrophotometer to detect MIC. To determine MBC, samples in the range of the turbidity threshold after 24 h were transferred onto blood agar and evaluated for growth after 24 h. Different MICs and MBCs were observed in all disinfectants against each microorganism. The lowest MIC and MBC against S. mutans (60 mg/L) were obtained from PHBM. The lowest values against L. rhamnosus (15 mg/L, 30 mg/L), A. viscosus (30 mg/L), and L. acidophilus (15 mg/L, 30 mg/L) were determined by OCT. PHBM and OCT have the potential to be replaced with CHX because they were effective against cariogenic microorganisms.
Topics: Agar; Anti-Bacterial Agents; Anti-Infective Agents, Local; Biguanides; Chlorhexidine; Dental Caries; Gram-Positive Bacteria; Imines; Microbial Sensitivity Tests; Pyridines; Reproducibility of Results; Spectrophotometry; Time Factors
PubMed: 27901206
DOI: 10.1590/1807-3107BOR-2016.vol30.0125 -
Scanning 2021To compare the effects of bleaching associated with Er:YAG and Nd:YAG laser on enamel structure and mixed biofilm formation on teeth surfaces.
OBJECTIVE
To compare the effects of bleaching associated with Er:YAG and Nd:YAG laser on enamel structure and mixed biofilm formation on teeth surfaces.
MATERIALS AND METHODS
Sixty-eight enamel samples were randomly divided into four groups ( = 17), control, Opalescence Boost only, Opalescence Boost plus Er: YAG laser, and Opalescence Boost plus Nd:YAG laser. The structure was observed using SEM after bleaching. Subsequently, the treated enamel samples were also cultured in suspensions of , , , and () for 24 and 48 h. Biofilm formation was quantified by crystal violet staining, and the structure was visualized by confocal laser scanning microscopy. The data were analyzed using the Kruskal-Wallis method.
RESULTS
The enamel structure significantly changed after bleaching. There was no obvious difference in the biofilm formation after 24 h; however, after 48 hours, the amount of biofilm increased significantly. Remarkably, the amount was significantly higher on enamel bleached only, however, there was no significant difference between samples bleached with Er:YAG or Nd:YAG laser compared to the control.
CONCLUSIONS
Bleaching only appeared to markedly promote biofilm formation after 48 h, and the biofilms on samples bleached with Er:YAG or Nd:YAG laser did not change significantly, showing that bleaching with Er:YAG or Nd:YAG laser can be safely applied in clinical practice.
Topics: Biofilms; Dental Enamel; Lasers, Solid-State; Tooth Bleaching; Humans
PubMed: 35003484
DOI: 10.1155/2021/6400605 -
Antimicrobial Agents and Chemotherapy Aug 2020Dental caries is the most common disease in the human mouth. is the primary cariogenic bacterium. Propolis is a nontoxic natural product with a strong inhibitory effect...
Dental caries is the most common disease in the human mouth. is the primary cariogenic bacterium. Propolis is a nontoxic natural product with a strong inhibitory effect on oral cariogenic bacteria. The polyphenol-rich extract from propolis inhibits growth and biofilm formation, as well as the genes involved in virulence and adherence, through the inhibition of glucosyltransferases (GTF). However, because the chemical composition of propolis is highly variable and complex, the mechanism of its antimicrobial action and the active compound are controversial and not completely understood. Caffeic acid phenethyl ester (CAPE) is abundant in the polyphenolic compounds from propolis, and it has many pharmacological effects. In this study, we investigated the antibacterial effects of CAPE on common oral cariogenic bacteria (, , , and ) and its effects on the biofilm-forming and cariogenic abilities of CAPE shows remarkable antimicrobial activity against cariogenic bacteria. Moreover, CAPE also inhibits the formation of biofilms and their metabolic activity in mature biofilms. Furthermore, CAPE can inhibit the key virulence factors of associated with cariogenicity, including acid production, acid tolerance, and the bacterium's ability to produce extracellular polysaccharides (EPS), without affecting bacterial viability at subinhibitory levels. In conclusion, CAPE appears to be a new agent with anticariogenic potential, not only via inhibition of the growth of cariogenic bacteria.
Topics: Anti-Bacterial Agents; Anti-Infective Agents; Biofilms; Caffeic Acids; Dental Caries; Humans; Phenylethyl Alcohol; Streptococcus mutans
PubMed: 32540977
DOI: 10.1128/AAC.00251-20