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Journal of Conservative Dentistry : JCD 2020The aim was (1) to study the cytotoxicity of novel Bioactive Caries-detecting Dye solution (BCD) and its antimicrobial activity against , , , and and (2) comparative...
Novel bioactive caries-detecting dye solution: Cytotoxicity, antimicrobial activity, scanning electron microscope, and stereomicroscopic analysis in diagnosis of dental caries.
AIM
The aim was (1) to study the cytotoxicity of novel Bioactive Caries-detecting Dye solution (BCD) and its antimicrobial activity against , , , and and (2) comparative assessment of BCD and Carie-Care for efficient removal of caries (stereomicroscope) and dentin tubule occlusion (scanning electron microscope [SEM]).
MATERIALS AND METHODS
For BCD cytotoxic study (direct contact method), colorimetric MTT assay, and cell line study(L929 mouse fibroblast NCTC clone 929 strain L) was performed. Xenetix 350, chitosan, nanohydroxyapatite (nHA), BCD, and Carie-Care solutions were subjected to the antimicrobial activity through blood agar well diffusion method, and the minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were determined. On 20 extracted human carious teeth a comparative pilot study was done for BCD (Group A, = 10) and Carie-Care (Group B, = 10), and evaluated visually and radiographically. After mechanical excavation of caries with a spoon excavator, teeth sectioned longitudinally and stereomicroscopically were evaluated (8x-40x) by two observers. The percentage of dentinal tubule occlusion was evaluated with SEM for both solutions. Statistical kappa analysis of agreement was 0.7-0.8 ( < 0.01). Mann-Whitney test ranks and Wilcoxon signed-rank test ( = 0.01) were applied.
RESULTS
Cytotoxicity test revealed BCD to be nontoxic and biocompatible. Antimicrobial tests (zone of inhibition) showed BCD > chitosan > chlorhexidine > Carie-Care > Xenetix 350 > nHA. MIC and MBC values suggested chlorhexidine > BCD > Carie-Care. Stereomicroscopic analysis showed effective mechanical removal of caries in BCD without residual dye in the dentinal tubules as compared to Carie-Care. Dentinal tubule occlusion (SEM analysis) was 80%-85% for BCD and 10% for Carie-Care.
CONCLUSIONS
Profound synergistic effect for BCD was observed with advantage of radiographic assessment.
PubMed: 33223647
DOI: 10.4103/JCD.JCD_154_20 -
Microorganisms Nov 2020may be key in tooth biofilm formation, but information about demographics, bacterial partners, and binding ligands is limited. The aims of this study were to explore 's...
may be key in tooth biofilm formation, but information about demographics, bacterial partners, and binding ligands is limited. The aims of this study were to explore 's demography by age and colonization site (plaque and saliva), in vitro bacterial-bacterial interactions in coaggregation and coadhesion assays, and glycolipids as potential binding ligands in thin-layer chromatogram binding assays. prevalence increased from 3 months to 18 years old, with 90% and 100% prevalence in saliva and tooth biofilm, respectively. aggregated in saliva in a dose-dependent manner but lacked the ability to bind to saliva-coated hydroxyapatite. In vivo, abundance paralleled that of sp. , subsp. , and sp. In vitro, bound both planktonic and surface-bound , , and . In addition, exhibited the ability to bind glycolipids isolated from human erythrocytes (blood group O), human granulocytes, rabbit intestine, human meconium, and rat intestine. Binding assays identified candidate carbohydrate ligands as isoglobotriaosylceramide, Galα3-isoglobotriaosylceramide, lactotriaosylceramide, lactotetraosylceramide, neolactotetraosylceramide, and neolactohexaosylceramide. Thus, likely uses specific plaque bacteria to adhere to the biofilm and may interact with human tissues through carbohydrate interactions.
PubMed: 33202844
DOI: 10.3390/microorganisms8111780 -
Frontiers in Microbiology 2020In view of increasing resistance against antibiotics and antiseptics, antimicrobial photodynamic therapy (aPDT) may be a promising approach for use in dentistry. The aim...
INTRODUCTION
In view of increasing resistance against antibiotics and antiseptics, antimicrobial photodynamic therapy (aPDT) may be a promising approach for use in dentistry. The aim of this study was to investigate the mechanism of action of aPDT with the phenalene-1-one derivatives SAPYR and SA-PN-05 as photosensitizers by evaluating bacterial ability to replicate, membrane integrity, metabolic activity, and formation of reactive oxygen species (ROS) in biofilms of , , and .
MATERIALS AND METHODS
Single-species biofilms (, , and ) were cultured under aerobic conditions for 48 h followed by treatment with the photosensitizers SAPYR and SA-PN-05 at various concentrations (0, 50, 100, 500 μM) and different incubation periods of 5, 10, 20, and 30 min and subsequent irradiation for 10 min (Waldmann PIB 3000; λ = 360-600 nm; 50 mW/cm; 30 J/cm). Control samples were treated with dHO and kept in dark for the same periods. Bacterial ability to replicate was evaluated by colony forming unit (CFU) assay. The cytoplasmic membrane integrity was investigated by flow cytometry using SYBR Green and propidium iodide and visualized by scanning and transmission electron microscopy. For SAPYR, metabolic activity and formation of intracellular ROS after irradiation were evaluated via luminescence and fluorometric assays, respectively.
RESULTS
SAPYR showed antimicrobial effects (>3 log CFU reduction) on after 5 min and on after 20 min incubation and light activation. For , CFU reduction was >2 log after 30 min of incubation. SA-PN-05 showed an antimicrobial effect after 5 min for all bacteria. Membrane damage upon aPDT with SAPYR was observed for , but not for and . Following treatment with SA-PN-05, irradiated samples and dark controls of all three species showed loss of membrane integrity. Luminescence and fluorometric assays showed a reduction in metabolic activity and an increase in formation of intracellular ROS in all three species upon aPDT treatment with SAPYR.
CONCLUSION
The observed loss in ability to replicate upon aPDT with SAPYR in single-species biofilms may be due to an increase in formation of intracellular ROS upon photodynamic treatment.
PubMed: 33193252
DOI: 10.3389/fmicb.2020.589364 -
Antibiotics (Basel, Switzerland) Oct 2020Actinomycosis is a chronic bacterial infection characterized by continuous local spread, irrespective of anatomical barriers, and granulomatous suppurative inflammation....
Actinomycosis is a chronic bacterial infection characterized by continuous local spread, irrespective of anatomical barriers, and granulomatous suppurative inflammation. Due to its expansive local growth, it can simulate a malignant tumour. Subsequent hematogenous dissemination to distant organs can mimic metastases and further increase suspicion for malignancy. A case of severe disseminated pelvic actinomycosis associated with intrauterine device is described here. The patient presented with a pelvic mass mimicking a tumour, bilateral ureteral obstruction, ascites, multinodular involvement of the liver, lungs and spleen, inferior vena cava thrombosis and extreme cachexia. Actinomycosis was diagnosed by liver biopsy and confirmed by culture of from extracted intrauterine contraceptive device (IUD). Prolonged treatment with aminopenicillin and surgery resulted in recovery with moderate sequelae.
PubMed: 33137889
DOI: 10.3390/antibiotics9110748 -
Journal of Oral Microbiology Oct 2020: Due to the increasing emergence of multi-resistant bacteria the search for alternative antimicrobial substances is of high interest. Promising agents are antimicrobial...
: Due to the increasing emergence of multi-resistant bacteria the search for alternative antimicrobial substances is of high interest. Promising agents are antimicrobial peptides which are host defense molecules of the innate immune system in a wide range of different species. : The aim of this study was to assess the activity of nisin, melittin, lactoferrin, parasin-1 and LL-37 against 35 oral bacteria and employing the gold standard method for anaerobic susceptibility testing. : The activity of the peptides was determined by an agar dilution method under anaerobic and aerobic conditions. The test media contained final peptide concentrations between 0.125 µg/ml and 8 µg/ml (melittin, lactoferrin, parasin-1, LL-37) and between 0.125 µg/ml and 128 µg/ml (nisin). : Nisin completely inhibited the growth of sp., and . Melittin and lactoferrin reduced the growth of sp., (melittin) and (lactoferrin). Parasin-1 and LL-37 showed no activity. : AMPs, especially nisin and to a smaller degree lactoferrin, might be promising alternatives to antibiotics because of their antimicrobial activity, high resistance to environmental conditions and partially low costs.
PubMed: 33133417
DOI: 10.1080/20002297.2020.1829405 -
Microorganisms Oct 2020is a commensal polymorphic and opportunistic fungus, which usually resides as a small community in the oral cavities of a majority of humans. The latter eco-system...
is a commensal polymorphic and opportunistic fungus, which usually resides as a small community in the oral cavities of a majority of humans. The latter eco-system presents this yeast varied opportunities for mutualistic interactions with other cohabitant oral bacteria, that synergizes its persistence and pathogenicity. Collectively, these communities live within complex plaque biofilms which may adversely affect the oral health and increase the proclivity for oral candidiasis. The proteome of such oral biofilms with myriad interkingdom interactions are largely underexplored. Herein, we employed limma differential expression analysis, and cluster analysis to explore the proteomic interactions of biofilms with nine different common oral bacterial species, , , , , , , , , and . Interestingly, upon exposure of biofilms to the foregoing heat-killed bacteria, the proteomes of the fungus associated with cellular respiration, translation, oxidoreductase activity, and ligase activity were significantly altered. Subsequent differential expression and cluster analysis revealed the subtle, yet significant alterations in the proteome, particularly on exposure to bacteria with dissimilar cell morphologies, and Gram staining characteristics.
PubMed: 33036329
DOI: 10.3390/microorganisms8101541 -
IDCases 2020Pott's puffy tumor is characterized by forehead swelling from subperiosteal abscess and frontal bone osteomyelitis. It is encountered mainly in children; rarely in...
Pott's puffy tumor is characterized by forehead swelling from subperiosteal abscess and frontal bone osteomyelitis. It is encountered mainly in children; rarely in adults. When it does occur in the latter population, the most common risk factors include head trauma, sinusitis, or cocaine abuse. Generally, the organisms thought to be involved include streptococci, staphylococci and oral anaerobic flora. We present a case of a 53 year old female who presented with forehead swelling of 3 month duration after a dental procedure, found to be secondary to . Actinomyces is a very rare etiology of this disease and has been reported only twice earlier in the literature. We present an uncommon infectious disease along with summary of clinical characteristics of this entity in the adult population.
PubMed: 33033689
DOI: 10.1016/j.idcr.2020.e00974 -
Dental Materials Journal Jan 2021Zinc-fluoride glass nanoparticles (Zinc-F) release several ions, such as fluoride, zinc and calcium ions, through acid-base reactions. The aim of this study was to...
Zinc-fluoride glass nanoparticles (Zinc-F) release several ions, such as fluoride, zinc and calcium ions, through acid-base reactions. The aim of this study was to evaluate the antibacterial and cytotoxic properties of Zinc-F. Antibacterial tests showed that a Zinc-F eluting solution significantly reduced the turbidity and colony-forming units of Streptococcus mutans and Actinomyces naeslundii, compared to that of calcium-fluoroaluminosilicate glass nanoparticles without zinc ions. In live/dead staining, Zinc-F eluate significantly decreased green-stained bacterial cells, indicating live cells, compared with the control (no application). Human dentin coated with Zinc-F showed suppressed S. mutans and A. naeslundii biofilm formation. Additionally, Zinc-F eluate showed low cytotoxic effects in osteoblastic and fibroblastic cells. Therefore, our findings suggested that Zinc-F exhibits antibacterial and biocompatible properties through multiple-ion release.
Topics: Actinomyces; Anti-Bacterial Agents; Biofilms; Fluorides; Humans; Nanoparticles; Streptococcus mutans; Zinc
PubMed: 32999216
DOI: 10.4012/dmj.2019-176 -
Nutrients Sep 2020In search for natural products with antimicrobial properties for use in the prevention and treatment of periodontitis, the purpose of this investigation was to evaluate...
In search for natural products with antimicrobial properties for use in the prevention and treatment of periodontitis, the purpose of this investigation was to evaluate the antimicrobial activity of two omega-3 fatty acids, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), using an in vitro multi-species subgingival biofilm model including , , , , , and . The antimicrobial activities of EPA and DHA extracts (100 µM) and the respective controls were assessed on 72 h biofilms by their submersion onto discs for 60 s. Antimicrobial activity was evaluated by quantitative polymerase chain reaction (qPCR), confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). ANOVA with Bonferroni correction was used to evaluate the antimicrobial activity of each of the fatty acids. Both DHA and EPA significantly reduced ( < 0.001 in all cases) the bacterial strains used in this biofilm model. The results with CLSM were consistent with those reported with qPCR. Structural damage was evidenced by SEM in some of the observed bacteria. It was concluded that both DHA and EPA have significant antimicrobial activity against the six bacterial species included in this biofilm model.
Topics: Analysis of Variance; Anti-Bacterial Agents; Biofilms; Docosahexaenoic Acids; Eicosapentaenoic Acid; Gingiva; Humans; Microbial Viability; Microscopy, Confocal; Models, Biological; Real-Time Polymerase Chain Reaction
PubMed: 32937742
DOI: 10.3390/nu12092812 -
Antibiotics (Basel, Switzerland) Aug 2020(1) Background: Antimicrobial agents such as chlorhexidine (CHX) are commonly used in oral plaque control. However, sometimes those agents lack antimicrobial efficiency...
(1) Background: Antimicrobial agents such as chlorhexidine (CHX) are commonly used in oral plaque control. However, sometimes those agents lack antimicrobial efficiency or cause undesired side effects. To identify alternative anti-infective agents, the present study investigated the antibacterial activity of all-fruit juices derived from blackcurrant, redcurrant, cranberry and raspberry on common oral pathogenic gram-positive and gram-negative bacteria (, , , , , , , ). (2) Methods: Antibacterial efficiency was evaluated by agar diffusion assay and in direct contact with bacteria in planktonic culture. Furthermore, cytotoxicity on human gingival fibroblasts was determined. (3) Results: Blackcurrant juice was most efficient at suppressing bacteria; followed by the activity of redcurrant and cranberry juice. Raspberry juice only suppressed significantly. Only high-concentrated blackcurrant juice showed minimal cytotoxic effects which were significantly less compared to the action of CHX. (4) Conclusion: Extracts from natural berry juices might be used for safe and efficient suppression of oral pathogenic bacterial species.
PubMed: 32847029
DOI: 10.3390/antibiotics9090533