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Colloids and Surfaces. B, Biointerfaces Jun 2020Dental materials are susceptible to dental plaque formation, which increases the risk of biofilm-associated oral diseases. Physical-chemical properties of dental...
Dental materials are susceptible to dental plaque formation, which increases the risk of biofilm-associated oral diseases. Physical-chemical properties of dental material surfaces can affect salivary pellicle formation and bacteria attachment, but relationships between these properties have been understudied. We aimed to assess the effects of surface properties and adsorbed salivary pellicle on Streptococcus gordonii adhesion to traditional dental materials. Adsorption of salivary pellicle from one donor on gold, stainless steel, alumina and zirconia was monitored with a quartz crystal microbalance with dissipation monitoring (QCM-D). Surfaces were characterized by X-ray photoelectron spectroscopy, atomic force microscopy and water contact angles measurement before and after pellicle adsorption. Visualization and quantification of Live/Dead stained bacteria and scanning electron microscopy were used to study S. gordonii attachment to materials with and without pellicle. The work of adhesion between surfaces and bacteria was also determined. Adsorption kinetics and the final thickness of pellicle formed on the four materials were similar. Pellicle deposition on all materials increased surface hydrophilicity, surface energy and work of adhesion with bacteria. Surfaces with pellicle had significantly more attached bacteria than surfaces without pellicle, but the physical-chemical properties of the dental material did not significantly alter bacteria attachment. Our findings suggested that the critical factor increasing S. gordonii attachment was the salivary pellicle formed on dental materials. This is attributed to increased work of adhesion between bacteria and substrates with pellicle. New dental materials should be designed for controlling bacteria attachment by tuning thickness, composition and structure of the adsorbed salivary pellicle.
Topics: Adsorption; Anti-Bacterial Agents; Chemistry, Physical; Dental Materials; Dental Pellicle; Humans; Microbial Sensitivity Tests; Particle Size; Streptococcus gordonii; Surface Properties
PubMed: 32172164
DOI: 10.1016/j.colsurfb.2020.110938 -
Archives of Oral Biology Apr 2020Aim of this in vitro study was to investigate erosive tooth loss in dependence of the enamel surface structure and presence of an acquired pellicle.
OBJECTIVE
Aim of this in vitro study was to investigate erosive tooth loss in dependence of the enamel surface structure and presence of an acquired pellicle.
METHODS
Enamel specimens from 19 bovine incisors (4 specimens/incisor) were allocated to four experimental groups (n = 19). The surfaces of half of the specimens were polished (two groups), while the other half was left native (two groups). Specimens of one polished and one native group were placed in pooled human saliva (30 min) for the formation of an acquired pellicle. Thereafter, all specimens were demineralized by superfusion with hydrochloric acid (17 min, pH 2.3) with collection of the superfluent. Erosive substance loss was determined by measuring the dissolved calcium content using a colorimetric assay with Arsenazo III reagent. Differences in erosive substance loss were statistically analyzed with respect to enamel surface and pellicle. A linear mixed effects model was fitted to the data and pairwise differences between groups were evaluated (significance level α= 0.05).
RESULTS
Enamel surface structure (p < 0.001) and presence of pellicle (p = 0.01) had a significant effect on erosive substance loss. Polished surfaces with pellicle showed the lowest cumulative calcium release [nmol Ca/mm] (means ± standard deviation: 48+/-5), followed by polished specimens without (51+/-9) and native specimens with pellicle (54+/-10). No significant differences were found between these groups. Highest cumulative calcium release was found for native specimens without pellicle (61+/-9; p < 0.05).
CONCLUSIONS
Both enamel surface structure and the acquired pellicle are important determinants of the susceptibility to erosive tooth loss.
Topics: Animals; Cattle; Citric Acid; Dental Enamel; Dental Enamel Solubility; Dental Pellicle; Humans; Hydrochloric Acid; Saliva; Tooth Erosion
PubMed: 32112967
DOI: 10.1016/j.archoralbio.2020.104686 -
Pakistan Journal of Medical Sciences 2020Chlorhexidine mouthrinses are considered a gold standard as an adjunct treatment of oral infections. However, owing to its toxicity, discoloration of tooth surface and...
OBJECTIVE
Chlorhexidine mouthrinses are considered a gold standard as an adjunct treatment of oral infections. However, owing to its toxicity, discoloration of tooth surface and the emerging prevalence of drug-resistant species, attention is being given to exploring natural alternatives to the drug.
METHODS
The experiment was carried out in Azra Naheed Center for Research and Development (ANCRD), Superior University, Lahore, Pakistan from September 2018 till May 2019. Biofilms and planktonic cells of alone and in combination with streptococci were subjected to chlorhexidine, and individually and to - combination. Kirby-Bauer test, antifungal susceptibility testing, CFU count and drug synergy assessment was done on planktonic cells. Dynamic biofilms were formed to mimic conditions similar to oral cavity and CFU was determined.
RESULTS
MIC of all three agents was higher against mixed species when compared to single species planktonic cells and biofilm. and demonstrated synergistic effects. The decrease in CFU count and minimum biofilm reduction to salivary pellicle caused by was comparable to that of chlorhexidine.
CONCLUSION
Thus, - combination demonstrated antimicrobial effects similar to chlorhexidine against planktonic cells and dynamic biofilm. It could serve as a possible natural, economical alternative to chlorhexidine mouthrinses usually recommended in dental clinics. However, studies are required to determine the correct dosage of these agents.
PubMed: 32063973
DOI: 10.12669/pjms.36.2.1457 -
Scientific Reports Jan 2020Pellicle is the initial proteinaceous layer that is formed almost instantaneously on all solid surfaces in the oral cavity. It is of essential relevance for any...
Pellicle is the initial proteinaceous layer that is formed almost instantaneously on all solid surfaces in the oral cavity. It is of essential relevance for any interactions and metabolism on the tooth surface. Up to now, there is no information on the metabolome of this structure. Accordingly, the present study aims to characterise the metabolomic profile of in-situ pellicle in children with different caries activity for the first time in comparison to saliva. Small molecules such as carbohydrates, amino acids, organic acids, and fatty acids, putatively involved in the formation of caries were quantified using mass spectrometry (MS)-based techniques, such as (stable isotope dilution analysis)-ultra-performance liquid chromatography-tandem MS and gas chromatography/electron ionisation-MS. Pellicle and corresponding saliva samples were collected from caries-active, caries-free and caries-rehabilitated 4- to 6-year-old children. The most abundant analytes in pellicle were acetic acid (1.2-10.5 nmol/cm), propionic acid (0.1-8.5 nmol/cm), glycine (0.7-3.5 nmol/cm), serine (0.08-2.3 nmol/cm), galactose (galactose + mannose; 0.035-0.078 nmol/cm), lactose (0.002-0.086 nmol/cm), glucose (0.018-0.953 nmol/cm), palmitic acid (0.26-2.03 nmol/cm), and stearic acid (0.34-1.81 nmol/cm). Significant differences depending on caries activity were detected neither in saliva nor in the corresponding pellicle samples.
Topics: Acetic Acid; Case-Control Studies; Child; Child, Preschool; Chromatography, Liquid; Dental Caries; Dental Pellicle; Glycine; Humans; Male; Metabolomics; Propionates; Saliva; Tandem Mass Spectrometry
PubMed: 31959821
DOI: 10.1038/s41598-020-57531-8 -
Biological Research Jan 2020The pellicle, the acellular organic material deposited on the surface of tooth enamel, has been thought to be derived from saliva. In this study, protein compositions of... (Comparative Study)
Comparative Study
BACKGROUND
The pellicle, the acellular organic material deposited on the surface of tooth enamel, has been thought to be derived from saliva. In this study, protein compositions of the pellicle, gingival crevicular fluid, and saliva collected from healthy adults were compared to elucidate the origin of pellicle proteins.
RESULTS
The pellicle, gingival crevicular fluid, and saliva from the parotid gland or mixed gland were collected; subsequently, protein expression in samples from the respective individual was compared by SDS-PAGE and mass spectrometry. Following SDS-PAGE, proteins in the major bands were identified by mass spectrometry. The band pattern of pellicle proteins appeared different from those of gingival crevicular fluid, or saliva samples. Using mass spectrometry, 13 proteins in these samples were identified. The relative abundance of the proteins was quantitatively analyzed using mass spectrometry coupled with stable isotope labeling and by western blot. Cystatin S and α-amylase detected in pellicle were enriched in saliva samples, but not in gingival crevicular fluid, by western blot, and their abundance ratios were high in saliva and low in gingival crevicular fluid when analyzed by stable isotope labeling. Serotransferrin, however, was found only in the pellicle and gingival crevicular fluid by western blot and its abundance ratio was low in saliva.
CONCLUSIONS
Our study revealed that the gingival crevicular fluid appears to contribute to pellicle formation in addition to saliva.
Topics: Adult; Blotting, Western; Dental Pellicle; Electrophoresis, Polyacrylamide Gel; Female; Gingival Crevicular Fluid; Humans; Male; Mass Spectrometry; Proteins; Saliva
PubMed: 31941552
DOI: 10.1186/s40659-020-0271-2 -
Scientific Reports Dec 2019The present clinical-experimental study aims to examine the effect of pure experimental fluoride solutions and stannous chloride on the initial oral bioadhesion under in...
The present clinical-experimental study aims to examine the effect of pure experimental fluoride solutions and stannous chloride on the initial oral bioadhesion under in situ conditions. After 1 min of pellicle formation on bovine enamel slabs, 12 subjects rinsed with 8 ml of the fluoride test solutions (NaF, NaPOF, AmF, SnF,) with 500 ppm fluoride concentration each for 1 min. Additionally, rinsing without a solution (control) and rinsing with 1563 ppm SnCl solution took place for 1 min. Afterwards, fluorescence microscopy took place to visualize bacterial adhesion and glucan formation (8 h oral exposition) with DAPI and ConA and the BacLight method. TEM was performed to visualize the pellicle ultrastructure together with EDX to detect stannous ions. The rinsing solutions with pure SnF and SnCl reduced significantly the initial bacterial colonization (DAPI). While, NaF and NaPOF showed no significant effect compared to the control. There was no significant difference between AmF, SnF and SnCl. All tested experimental solutions showed no reducing effect on the glucan formation. Considerable alterations of the pellicle ultrastructure resulted from rinsing with the Sn-containing solutions. SnF appears to be the most effective type of fluoride to reduce initial bacterial colonization in situ. The observed effects primarily have to be attributed to the stannous ions' content.
Topics: Animals; Bacteria; Bacterial Adhesion; Biofilms; Cattle; Dental Caries; Dental Enamel; Fluorides; Glucans; Humans; Ions; Microscopy, Fluorescence; Mouthwashes; Oxygen; Sodium Fluoride; Tin Compounds; Tin Fluorides; Tooth Erosion; Toothpastes; X-Rays
PubMed: 31811248
DOI: 10.1038/s41598-019-55083-0 -
BMC Complementary and Alternative... Nov 2019Dental caries is a biofilm-diet-dependent worldwide public health problem, and approaches against microorganisms in cariogenic biofilms are necessary.
BACKGROUND
Dental caries is a biofilm-diet-dependent worldwide public health problem, and approaches against microorganisms in cariogenic biofilms are necessary.
METHODS
The antimicrobial and antibiofilm activities of 12 Casearia sylvestris extracts (0.50 mg/mL) from different Brazilian biomes (Atlantic Forest, Cerrado, Caatinga, Pampa, and Pantanal) and varieties (sylvestris, lingua, and intermediate) were tested against two species found in cariogenic biofilms (Streptococcus mutans and Candida albicans). The extracts effective against S. mutans were used to evaluate the "adhesion strength" of this bacterium to the salivary pellicle and initial glucan matrix and the S. mutans-GtfB activity. Also, the antimicrobial activity against S. mutans of three fractions (methanol, ethyl acetate, and hexane; 0.25 mg/mL) from the extracts was evaluated.
RESULTS
Three extracts from the Atlantic Forest variety sylvestris (FLO/SC, GUA/CE, PRE/SP) reduced ≥50% (> 3 logs) S. mutans viable population (p < 0.0001 vs. vehicle), while two extracts from the same biome and variety (PAC/CE, PRE/SP) decreased ≥50% of the viable counts of C. albicans (p < 0.0001 vs. vehicle). For S. mutans biofilms, three extracts (GUA/CE, PAC/CE, PRE/SP) reduced the biomass by ≥91% (p > 0.0001 vs. vehicle) and 100% of the microbial population (p < 0.0001 vs. vehicle). However, for the fungal biofilm, two extracts (PAC/CE, PRE/SP) reduced the viable counts by ≥52% (p < 0.0001 vs. vehicle), but none reduced biomass. The extracts with higher antimicrobial and antibiofilm activities presented higher content of clerodane-type diterpenes and lower content of glycosylated flavonoids than the less active extracts. The extracts had no effect on the removal of cells adhered to the pellicle (p > 0.05 vs. vehicle) while promoted the detachment of a larger number of S. mutans cells from GtfB-glucan matrix (p < 0.0031 vs. vehicle), and FLO/SC, GUA/CE and PRE/SP reduced the quantity of glucans (p < 0.0136 vs. vehicle). Only the ethyl acetate fractions reduced the microbial population of S. mutans (p < 0.0001 vs. vehicle), except for one (PAC/CE). Among the ethyl acetate fractions, three from var. lingua (two from Cerrado, and one from Cerrado/Caatinga) reduced ≥83% of the microbial population.
CONCLUSIONS
C. sylvestris extracts from Atlantic Forest var. sylvestris and ethyl acetate fractions from Cerrado and Cerrado/Caatinga var. lingua may be used as a strategy against cariogenic microorganisms.
Topics: Anti-Infective Agents; Biofilms; Brazil; Candida albicans; Casearia; Dental Caries; Ecosystem; Humans; Microbial Sensitivity Tests; Plant Extracts; Streptococcus mutans
PubMed: 31718633
DOI: 10.1186/s12906-019-2717-z -
Scientific Reports Sep 2019Using Sprague-Dawley rats (350-450 g; n = 61) and the recently updated Walker-Mason rat scald burn model, we demonstrated that Pseudomonas aeruginosa readily...
Using Sprague-Dawley rats (350-450 g; n = 61) and the recently updated Walker-Mason rat scald burn model, we demonstrated that Pseudomonas aeruginosa readily formed biofilms within full-thickness burn wounds. Following the burn, wounds were surface-inoculated with P. aeruginosa in phosphate-buffered saline (PBS), while sterile PBS was used for controls. On post-burn days 1, 3, 7, and 11, animals were euthanized and samples collected for quantitative bacteriology, bacterial gene expression, complete blood cell counts, histology, and myeloperoxidase activity. Robust biofilm infections developed in the full-thickness burn wounds inoculated with 1 × 10 CFU of P. aeruginosa. Both histology and scanning electron microscopy showed the pathogen throughout the histologic cross-sections of burned skin. Quantigene analysis revealed significant upregulation of alginate and pellicle biofilm matrix genes of P. aeruginosa within the burn eschar. Additionally, expression of P. aeruginosa proteases and siderophores increased significantly in the burn wound environment. Interestingly, the host's neutrophil response to the pathogen was not elevated in either the eschar or circulating blood when compared to the control burn. This new full-thickness burn biofilm infection model will be used to test new anti-biofilm therapies that may be deployed with soldiers in combat for immediate use at the site of burn injury on the battlefield.
Topics: Animals; Biofilms; Burns; Disease Models, Animal; Male; Neutrophils; Pseudomonas Infections; Pseudomonas aeruginosa; Rats; Rats, Sprague-Dawley; Soft Tissue Injuries; Wound Infection; Wounds and Injuries
PubMed: 31541159
DOI: 10.1038/s41598-019-50003-8 -
Scientific Reports Sep 2019One mechanism of action for the anticaries effect of topical fluoridation is through precipitation of CaF. In this in vitro study energy-dispersive x-ray spectroscopy...
One mechanism of action for the anticaries effect of topical fluoridation is through precipitation of CaF. In this in vitro study energy-dispersive x-ray spectroscopy (EDX) is used as a semiquantitative method to detect enamel fluoride-precipitation under the influence of acidic and neutral pH-value and absence or presence of a salivary pellicle. Crowns of 30 human caries-free third molars were quartered into four specimens and the enamel surface ground flat and polished. Two specimens each were stored in human saliva (120 minutes pellicle formation). Teeth were randomly allocated into 6 treatment groups: NaF_a (experimental acidic sodium fluoride; 12500 ppmF, pH 4.75); NaF_n (experimental neutral sodium fluoride; 12500 ppmF, pH 7.0); GB_a (acidic gel base; 0 ppmF, pH 4.75); GB_n (neutral gel base; 0 ppmF, pH 7.0); AmF-NaF_a (experimental acidic amine/sodium fluoride; 12500 ppmF, pH 4.75); EG_a (acidic amine/sodium fluoride; Elmex Geleé, CP-GABA GmbH; 12500 ppmF, pH 4.75). Each gel was applied for 60 seconds to one specimen with and one specimen without pellicle. Two specimens served as controls (no gel, without/with pellicle). Atomic percent (At%) of O, F, Na, Mg, P, Ca was measured by EDX. ∆At% and Ca/P-ratios were calculated. EDX could semi-quantify superficial enamel fluoride-precipitation. Only specimens treated with acidic fluoride gels showed fluoride-precipitation, a salivary pellicle tended to decrease At%F.
Topics: Administration, Topical; Calcium Fluoride; Dental Enamel; Gels; Humans; Molar, Third; Spectrometry, X-Ray Emission
PubMed: 31530840
DOI: 10.1038/s41598-019-49742-5 -
MSystems Sep 2019Development of dental plaque begins with the adhesion of salivary bacteria to the acquired pellicle covering the tooth surface. In this study, we collected dental...
Development of dental plaque begins with the adhesion of salivary bacteria to the acquired pellicle covering the tooth surface. In this study, we collected dental plaque formed on hydroxyapatite disks for 6 h from 74 young adults and identified initial colonizing taxa based on full-length 16S rRNA gene sequences. A long-read, single-molecule sequencer, PacBio Sequel, provided 100,109 high-quality full-length 16S rRNA gene sequence reads from the early plaque microbiota, which were assigned to 90 oral bacterial taxa. The microbiota obtained from every individual mostly comprised the 21 predominant taxa with the maximum relative abundance of over 10% (95.8 ± 6.2%, mean ± SD), which included species as well as nonstreptococcal species. A hierarchical cluster analysis of their relative abundance distribution suggested three major patterns of microbiota compositions: a / sp. HMT-423-dominant profile, a //-dominant profile, and a complex profile with high diversity. No notable variations in the community structures were associated with the dental caries status, although the total bacterial amounts were larger in the subjects with a high number of caries-experienced teeth (≥8) than in those with no or a low number of caries-experienced teeth. Our results revealed the bacterial taxa primarily involved in early plaque formation on hydroxyapatite disks in young adults. Selective attachment of salivary bacteria to the tooth surface is an initial and repetitive phase in dental plaque development. We employed full-length 16S rRNA gene sequence analysis with a high taxonomic resolution using a third-generation sequencer, PacBio Sequel, to determine the bacterial composition during early plaque formation in 74 young adults accurately and in detail. The results revealed 21 bacterial taxa primarily involved in early plaque formation on hydroxyapatite disks in young adults, which include several streptococcal species as well as nonstreptococcal species, such as / / and Given that no notable variations in the microbiota composition were associated with the dental caries status, the maturation process, rather than the specific bacterial species that are the initial colonizers, is likely to play an important role in the development of dysbiotic microbiota associated with dental caries.
PubMed: 31481603
DOI: 10.1128/mSystems.00360-19