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1.
Braz. j. oral sci ; 22: e231137, Jan.-Dec. 2023. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1523140

RESUMO

The purpose of this in vitro study was to analyze the influence of nicotine on the extracellular polysaccharides in Fusobacterium nucleatum biofilm. Methods: F. nucleatum (ATCC 10953) biofilms supplemented with different concentrations of nicotine (0, 0.5, 1, 2, 4, and 8 mg/mL) were grown in two different BHI broth conditions [no sucrose and 1% sucrose]. Extracellular polysaccharides assay, pH measurements, and a spectrophotometric assay were performed. Data were submitted for ANOVA and Tukey honestly significant difference analyses (HSD) tests (α =.05). Results: Extracellular polysaccharides synthesis was influenced by an interaction between nicotine concentrations and growth medium solution containing sucrose (P<.05). The pH values declined in the sucrose-exposed biofilm were greater than in the group exposed only to nicotine (P<.05). The biofilm exposed to sucrose and nicotine had a higher total biofilm growth (P<.05) than the nicotine-treated biofilm without sucrose. Conclusions: Regardless of sucrose exposure, biofilms exposed to different nicotine concentrations influenced the amount of extracellular polysaccharides


Assuntos
Humanos , Polissacarídeos Bacterianos/síntese química , Fusobacterium nucleatum/crescimento & desenvolvimento , Biofilmes/crescimento & desenvolvimento , Nicotina/farmacologia , Doenças Periodontais/microbiologia , Espectrofotometria , Sacarose/administração & dosagem , Meios de Cultura , Cárie Dentária/microbiologia , Nicotina/administração & dosagem
2.
J. appl. oral sci ; 27: e20180699, 2019. graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1012504

RESUMO

Abstract Objective This study investigated the role of extracellular deoxyribonucleic acid (eDNA) on Enterococcus faecalis ( E. faecalis ) biofilm and the susceptibility of E. faecalis to sodium hypochlorite (NaOCl). Methodology E. faecalis biofilm was formed in bovine tooth specimens and the biofilm was cultured with or without deoxyribonuclease (DNase), an inhibitor of eDNA. Then, the role of eDNA in E. faecalis growth and biofilm formation was investigated using colony forming unit (CFUs) counting, eDNA level assay, crystal violet staining, confocal laser scanning microscopy, and scanning electron microscopy. The susceptibility of E. faecalis biofilm to low (0.5%) or high (5%) NaOCl concentrations was also analyzed by CFU counting. Results CFUs and biofilm formation decreased significantly with DNase treatment (p<0.05). The microstructure of DNase-treated biofilms exhibited less structured features when compared to the control. The volume of exopolysaccharides in the DNase-treated biofilm was significantly lower than that of control (p<0.05). Moreover, the CFUs, eDNA level, biofilm formation, and exopolysaccharides volume were lower when the biofilm was treated with DNase de novo when compared to when DNase was applied to matured biofilm (p<0.05). E. faecalis in the biofilm was more susceptible to NaOCl when it was cultured with DNase (p<0.05). Furthermore, 0.5% NaOCl combined with DNase treatment was as efficient as 5% NaOCl alone regarding susceptibility (p>0.05). Conclusions Inhibition of eDNA leads to decrease of E. faecalis biofilm formation and increase of susceptibility of E. faecalis to NaOCl even at low concentrations. Therefore, our results suggest that inhibition of eDNA would be beneficial in facilitating the efficacy of NaOCl and reducing its concentration.


Assuntos
Animais , Bovinos , Hipoclorito de Sódio/farmacologia , DNA Bacteriano/farmacologia , Enterococcus faecalis/crescimento & desenvolvimento , Enterococcus faecalis/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Biofilmes/efeitos dos fármacos , Desoxirribonucleases/farmacologia , Polissacarídeos Bacterianos/isolamento & purificação , Fatores de Tempo , Microscopia Eletrônica de Varredura , Contagem de Colônia Microbiana , Testes de Sensibilidade Microbiana , Reprodutibilidade dos Testes , Microscopia Confocal , Cavidade Pulpar/microbiologia
3.
J. appl. oral sci ; 27: e20180514, 2019. tab, graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1012510

RESUMO

Abstract Objectives: The aim of this study was to assess the effect of Myracrodruon urundeuva All. and Qualea grandiflora Mart. leaves hydroalcoholic extracts on viability and metabolism of a microcosm biofilm and on enamel demineralization prevention. Methodology: Microcosm biofilm was produced on bovine enamel using inoculum from pooled human saliva mixed with McBain saliva, under 0.2% sucrose exposure, for 14 days. The biofilm was daily-treated with the extracts for 1 min. At the end, it was analyzed with respect to viability by fluorescence, CFU counting and extracellular polysaccharides (phenol-sulphuric acid colorimetric assay) and lactic acid (enzymatic assay) production. The demineralization was measured by TMR. The data were compared using ANOVA or Kruskal-Wallis (p<0.05). Results: M. urundeuva All. at 100, 10 and 0.1 μg/mL and Q. grandiflora Mart. at 100 and 0.1 μg/mL reduced biofilm viability similarly to positive control (chlorhexidine) and significantly more than the negative-vehicle control (35% ethanol). M. urundeuva at 1000, 100 and 0.1 μg/mL were able to reduce both lactobacilli and mutans streptococci CFU counting, while Q. grandiflora (1000 and 1.0 μg/mL) significantly reduced mutans streptococci CFU counting. On the other hand, the natural extracts were unable to significantly reduce extracellular polysaccharides and lactic acid productions neither the development of enamel carious lesions. Conclusions: The extracts showed antimicrobial properties on microcosm biofilm, however, they had no effect on biofilm metabolism and caries protection.


Assuntos
Animais , Masculino , Bovinos , Extratos Vegetais/farmacologia , Desmineralização do Dente/prevenção & controle , Biofilmes/efeitos dos fármacos , Anacardiaceae/química , Myrtales/química , Anti-Infecciosos/farmacologia , Polissacarídeos Bacterianos/metabolismo , Saliva/química , Streptococcus mutans/efeitos dos fármacos , Microrradiografia/métodos , Contagem de Colônia Microbiana , Cariostáticos/farmacologia , Testes de Sensibilidade Microbiana , Reprodutibilidade dos Testes , Folhas de Planta/química , Ácido Láctico/metabolismo , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/microbiologia , Viabilidade Microbiana/efeitos dos fármacos , Lactobacillus/efeitos dos fármacos
4.
J. appl. oral sci ; 26: e20170113, 2018. graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-893693

RESUMO

Abstract Dental caries is a chronic progressive disease occurring in the tooth hard tissue due to multiple factors, in which bacteria are the initial cause. Both Streptococcus mutans and Streptococcus sanguinis are main members of oral biofilm. Helicobacter pylori may also be detected in dental plaque, playing an important role in the development of dental caries. Objective The aim of this study was to investigate the effect of H. pylori culture supernatant on S. mutans and S. sanguinis dual-species biofilm and to evaluate its potential ability on affecting dental health. Material and methods The effect of H. pylori supernatant on single-species and dual-species biofilm was measured by colony forming units counting and fluorescence in situ hybridization (FISH) assay, respectively. The effect of H. pylori supernatant on S. mutans and S. sanguinis extracellular polysaccharides (EPS) production was measured by both confocal laser scanning microscopy observation and anthrone-sulfuric acid method. The effect of H. pylori supernatant on S. mutans gene expression was measured by quantitative real-time PCR (qRT-PCR) assays. Results H. pylori supernatant could inhibit both S. mutans and S. sanguinis biofilm formation and EPS production. S. sanguinis inhibition rate was significantly higher than that of S. mutans. Finally, S. mutans bacteriocin and acidogenicity related genes expression were affected by H. pylori culture supernatant. Conclusion Our results showed that H. pylori could destroy the balance between S. mutans and S. sanguinis in oral biofilm, creating an advantageous environment for S. mutans, which became the dominant bacteria, promoting the formation and development of dental caries.


Assuntos
Streptococcus mutans/fisiologia , Streptococcus sanguis/fisiologia , Helicobacter pylori/fisiologia , Biofilmes , Placa Dentária/microbiologia , Plâncton/crescimento & desenvolvimento , Polissacarídeos Bacterianos/metabolismo , Streptococcus mutans/genética , Streptococcus sanguis/genética , Fatores de Tempo , Contagem de Colônia Microbiana , Expressão Gênica , Helicobacter pylori/genética , Hibridização in Situ Fluorescente , Microscopia Confocal , Cárie Dentária/microbiologia , Reação em Cadeia da Polimerase em Tempo Real
5.
J. appl. oral sci ; 24(5): 487-495, Sept.-Oct. 2016. graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: lil-797977

RESUMO

ABSTRACT Objective: Enterococcus faecalis is the dominant microbial species responsible for persistent apical periodontitis with ability to deeply penetrate into the dentin. Exopolysaccharides (EPS) contribute to the pathogenicity and antibiotic resistance of E. faecalis. Our aim was to investigate the antimicrobial activity of calcium hydroxide (CH), camphorated parachlorophenol (CMCP), and chlorhexidine (CHX) against E. faecalis in dentinal tubules. Material and Methods: Decoronated single-canal human teeth and semicylindrical dentin blocks were incubated with E. faecalis for 3 weeks. Samples were randomly assigned to six medication groups for 1 week (n=10 per group): CH + 40% glycerin-water solution (1:1, wt/vol); CMCP; 2% CHX; CH + CMCP (1:1, wt/vol); CH + CMCP (2:3, wt/vol); and saline. Bacterial samples were collected and assayed for colony-forming units. After dentin blocks were split longitudinally, confocal laser scanning microscopy was used to assess the proportion of viable bacteria and EPS production in dentin. Results: CMCP exhibited the best antimicrobial activity, while CH was the least sensitive against E. faecalis (p<0.05). CHX showed similar antimicrobial properties to CH + CMCP (1:1, wt/vol) (p>0.05). CH combined with CMCP inhibited EPS synthesis by E. faecalis, which sensitized biofilms to antibacterial substances. Moreover, increasing concentrations of CMCP decreased EPS matrix formation, which effectively sensitized biofilms to disinfection agents. Conclusion: The EPS matrix dispelled by CH paste with CMCP may be related to its bactericidal effect; the visualization and analysis of EPS formation and microbial colonization in dentin may be a useful approach to verify medicaments for antimicrobial therapy.


Assuntos
Humanos , Adolescente , Adulto , Adulto Jovem , Polissacarídeos Bacterianos/química , Irrigantes do Canal Radicular/farmacologia , Veículos Farmacêuticos/farmacologia , Hidróxido de Cálcio/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Dentina/efeitos dos fármacos , Antibacterianos/farmacologia , Fatores de Tempo , Cânfora/farmacologia , Contagem de Colônia Microbiana , Clorofenóis/farmacologia , Reprodutibilidade dos Testes , Estatísticas não Paramétricas , Microscopia Confocal , Biofilmes/efeitos dos fármacos , Cavidade Pulpar/efeitos dos fármacos , Cavidade Pulpar/microbiologia , Dentina/microbiologia , Combinação de Medicamentos , Viabilidade Microbiana/efeitos dos fármacos
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