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1.
Rev. Fac. Odontol. (B.Aires) ; 36(84): 21-26, 2021. tab
Article in Spanish | LILACS | ID: biblio-1363852

ABSTRACT

La terapia endodóntica tiene como uno de sus objetivos lograr la completa desinfección del sistema de conductos radiculares. Por esto, se deben seleccionar sustancias irrigantes que tengan la capacidad de eliminar todo el contenido de dicho sistema. La acción antimicrobiana es una de las características más importantes a tener en cuenta en la elección. El hipoclorito de sodio (NaOCl) tiene capacidad bactericida sobre muchos de los microorganismos de la flora endodóntica. El Enterococcus faecalis es una bacteria altamente resistente a antibacterianos que sobrevive en condiciones extremas. El ácido hipocloroso (HOCl) es una molécula derivada del NaOCl que ha demostrado tener alto poder bactericida sobre cepas patogénicas bucales. El objetivo de este trabajo fue evaluar y comparar la efectividad antimicrobiana in vitro del NaOCl 2.5% y el HOCl al 5% frente a Enterococcus faecalis. Una suspensión de Enterococcus faecalis (ATCC29212), de turbidez 0.5 en escala de McFarland, fue inoculada en varios tubos de ensayo, los cuales contenían cada antimicrobiano. Se dejaron actuar durante 1, 5 y 10 minutos para luego neutralizarlos e inclubarlos a 37º C en condiciones de capnofilia durante 48 hs. Todo el procedimiento se realizó por quintuplicado. Los resultados se midieron mediante recuento de UFC/ml. No se evidenció presencia de Enterococcus faecalis en las placas que contenían la solución de NaOCl al 2.5% como tampoco en aquellas que contenían HOCl al 5%. In vitro, el HOCl y el NaOCl en las concentraciones probadas, eliminaron completamente las cepas de Enterococcus faecalis (AU)


Subject(s)
Sodium Hypochlorite/therapeutic use , Enterococcus faecalis/drug effects , Hypochlorous Acid/therapeutic use , Anti-Bacterial Agents/therapeutic use , Root Canal Irrigants/therapeutic use , In Vitro Techniques , Colony Count, Microbial , Culture Media , Dental Pulp Cavity/microbiology
2.
Int. j. odontostomatol. (Print) ; 14(4): 632-638, dic. 2020. tab, graf
Article in English | LILACS | ID: biblio-1134550

ABSTRACT

ABSTRACT: The aim of this in vitro study was to investigate the influence of ethylenediaminetetraacetic acid (EDTA) associated with the benzalkonium chloride (BAK) on the adhesion and formation of Enterococcus faecalis biofilms attached to coated dentin. Discs standard bovine dentin blocks were treated with the coating materials evaluated: Saline solution (control), 17 % EDTA, 17 % EDTA associated with 1 % BAK for 5 minutes and subsequently washed with saline solution. Afterwards, biofilms of E. faecalis (ATCC 29212) were grown on the surface of coated dentin blocks for time intervals of 1 hour and 7 days (n = 20) and were subsequently washed with phosphate-buffered saline (PBS). Bacterial viability and total biovolume were analyzed by confocal laser scanning microscopy (CLSM) using the Live/Dead technique. Nonparametric Kruskal-Wallis followed by Dunn tests were used to determine statistical differences (a = 5 %). The 17 % EDTA + 1 % BAK group showed significantly lower biovolume and bacterial viability values at the end of 1 hour (p < 0.05). After 7 days of contamination, the 17 % EDTA and 17 % EDTA + 1 % BAK groups showed similar results that differed statistically from those of the control group (p < 0.05). The saline solution group showed higher values. The use of BAK associated with EDTA on dentin blocks surfaces before exposure to contamination was able to interfere in the adhesion of E. faecalis to dentin. Also, dentin treatment by BAK associated with a chelating agent influences the secondary biofilm formation, which could have important effects on the long-term success of root canal treatment.


RESUMEN: El objetivo del estudio consistió en investigar in vitro, la influencia del ácido etilendiamino-tetraacético (EDTA) con cloruro de benzalconio (BAK) en la adhesión y formación de biopelículas de Enterococcus faecalis a la dentina. Discos de dentina bovina fueron tratadas con solución salina (control), 17 % de EDTA, 17% de EDTA asociado con 1 % de BAK durante 5 minutos y lavadas con solución salina. Las biopelículas de E. faecalis (ATCC 29212) se cultivaron sobre los discos de dentina durante intervalos de tiempo de 1 hora y 7 días (n = 20), lavados con solución salina tamponada con fosfato (PBS). La viabilidad bacteriana y el biovolumen total se analizaron mediante microscopía de barrido por láser (CLSM) utilizando la técnica Live / Dead. Se realizó prueba no paramétrica de Kruskal-Wallis, seguida por Dunn con una diferencia estadística (a = 5 %). El grupo de 17 % EDTA + 1 % BAK mostró valores significativamente menores de biovolumen y viabilidad bacteriana al final de 1 hora (p < 0,05). Después de 7 días de contaminación, los grupos de 17 % EDTA y 17 % EDTA + 1 % BAK mostraron resultados similares que diferían estadísticamente del grupo control (p < 0,05). La solución salina mostró valores más altos. La asociación de BAK con EDTA antes de la contaminación interfirió en la adhesión de E. faecalis. Además, el tratamiento de la dentina por BAK asociado con EDTA influye en la formación de biopelículas secundarias, lo que podría tener efectos importantes sobre el éxito a largo plazo del tratamiento del conducto radicular.


Subject(s)
Animals , Cattle , Bacterial Adhesion/drug effects , Edetic Acid/pharmacology , Enterococcus faecalis/growth & development , Enterococcus faecalis/drug effects , Biofilms/drug effects , Dentin/microbiology , Benzalkonium Compounds/pharmacology , Statistical Analysis , Microscopy, Confocal , Saline Solution
3.
Int. j. odontostomatol. (Print) ; 14(3): 448-456, 2020. tab, graf
Article in English | LILACS | ID: biblio-1114920

ABSTRACT

Enterococci are important nosocomial pathogens due to their intrinsic multiresistance and the acquisition of new antibiotic resistance genes (ARG). Enterococcus faecalis has been shown to be one of the main pathogens in persistent endodontic infections, therefore, the main objective of this study was to evaluate the phenotype and resistance genotype of strains of E. faecalis isolated from teeth with persistent endodontic lesions, to the most commonly prescribed antibiotics in dentistry. Thirteen strains of E. faecalis of different pulsotype were analyzed to evaluate the susceptibility to antibiotics, amoxicillin, amoxicillin/clavulanic acid, tetracycline, erythromycin and metronidazole, using the Epsilometer test (E- test) and the presence of beta-lactamases with nitrocefin test. Finally, the detection of ARG was performed with a molecular polymerase chain reaction (PCR) technique and confirmed by the sequencing of the amplification products. Fisher's exact test was used, using 95 % confidence. Regarding the phenotype of resistance, the evaluated strains, independent of the pulsotype, were totally resistant to the action of metronidazole. Antibiotics with higher minimum inhibitory concentration (MIC) after metronidazole include tetracycline and erythromycin. In contrast, lower MIC are applied to the combination of amoxicillin with clavulanic acid. The nitrocefin test was positive only in one strain. Genotypically, two genetically distant strains isolated from a single patient, presented a genotype of resistance to erythromycin, determined by the presence of the ermB gene. No statistically significant relationship was found between phenotypic resistance and the presence of ARG in relation to erythromycin (p> 0.05). It was concluded that isolates of E. faecalis from persistent endodontic infections showed phenotypes of resistance to several antimicrobial agents, all of which were susceptible to amoxicillin/clavulanic acid. Periodic evaluation of susceptibility to antibiotics is suggested as an important practice for the surveillance of antibiotic resistance in oral strains.


Los enterococos son importantes patógenos nosocomiales debido a su multi resistencia intrínseca y la adquisición de nuevos genes de resistencia a los antibióticos (ARG). Enterococcus faecalis es uno de los principales patógenos en infecciones endodónticas persistentes, por lo tanto, el objetivo principal de este estudio fue evaluar el fenotipo y el genotipo de resistencia de cepas de E. faecalis aisladas de dientes con lesiones endodóncicas persistentes, a los antibióticos comúnmente recetados en odontología. Se analizaron 13 cepas de E. faecalis de diferentes pulsotipos para evaluar la susceptibilidad a los antibióticos, amoxicilina, amoxicilina / ácido clavulánico, tetraciclina, eritromicina y metronidazol, utilizando la prueba de Epsilometría (E-test) y la presencia de beta-lactamasas con prueba de nitrocefina. Finalmente, la detección de ARG se realizó con una técnica molecular de reacción en cadena de la polimerasa (PCR) y se confirmó mediante la secuenciación de los productos de amplificación. Se utilizó la prueba exacta de Fisher, con un 95 % de confianza. En cuanto al fenotipo de resistencia, las cepas evaluadas, independientes del pulsotipo, fueron totalmente resistentes a la acción del metronidazol. Los antibióticos con los valores más altos de concentración mínima inibitoria (CMI) después del metronidazol incluyen tetraciclina y eritromicina. En contraste, las CMI mas bajas se aplican a la combinación de amoxicilina con ácido clavulánico. La prueba de nitrocefina fue positiva solo en una cepa. Genotípicamente, dos cepas distantes genéticamente, aisladas de un mismo paciente fueron positivas para el gen ermB. No se encontró una relación estadísticamente significativa entre la resistencia fenotípica y la presencia de ARG en relación con la eritromicina (p> 0,05). Se concluyó que los aislamientos de E. faecalis de infecciones endodónticas persistentes mostraron fenotipos de resistencia a varios agentes antimicrobianos, todos los cuales fueron susceptibles a amoxicilina / ácido clavulánico. Se sugiere una evaluación periódica de la susceptibilidad a los antibióticos como una práctica importante para la vigilancia de la resistencia a los antibióticos en las cepas orales.


Subject(s)
Humans , Enterococcus faecalis/drug effects , Enterococcus faecalis/genetics , Dental Pulp Cavity/microbiology , Anti-Bacterial Agents/pharmacology , Tetracycline , Microbial Sensitivity Tests , Erythromycin , Polymerase Chain Reaction , Clavulanic Acid/pharmacology , Drug Resistance, Bacterial/genetics , Amoxicillin/pharmacology , Metronidazole
4.
Int. j. odontostomatol. (Print) ; 14(3): 367-372, 2020. tab, graf
Article in Spanish | LILACS | ID: biblio-1114909

ABSTRACT

Este estudio in vitro evaluó la influencia de la dentina sobre el efecto antibacteriano contra Enterococcus faecalis ATCC 29212 de dos concentraciones de Hipoclorito de Sodio (NaOCl) 2,5 % y 5 %. Se empleó polvo de dentina a partir de dientes humanos (84 µg/ml) y la supervivencia de la bacteria se evaluó realizando recuento de unidades formadoras de colonias (UFC) a los 10, 30 y 60 segundos. Los datos se analizaron con la prueba estadística ANOVA factorial no encontrándose diferencias estadísticamente significativas entre los grupos con dentina y sin dentina. En conclusión, la dentina en este estudio no influyó en el efecto antibacteriano del Hipoclorito de Sodio en ninguna concentración, ni en los tiempos.


This in vitro study evaluated the influence of dentin on the antibacterial effect against Enterococcus faecalis ATCC 29212 of two concentrations of Sodium Hypochlorite NaOCl 2.5 % and 5 %. Dentin powder was used from human teeth (84 mg/ml) and the survival of the bacteria was evaluated by counting colony forming units (CFU) at 10, 30 and 60 seconds. The data were analyzed with the statistical ANOVA factorial test, finding no statistically significant differences between the groups with and without dentin. In conclusion, the dentin in this study had no inhibitory effect on antibacterial activity of Sodium Hypochlorite and any concentration, nor over time.


Subject(s)
Humans , Sodium Hypochlorite/pharmacology , Enterococcus faecalis/drug effects , Dentin/drug effects , Anti-Bacterial Agents/pharmacology , Powders , In Vitro Techniques , Microbial Sensitivity Tests , Analysis of Variance , Factor Analysis, Statistical , Enterococcus faecalis/growth & development , Dentin/microbiology
5.
J. appl. oral sci ; 28: e20190516, 2020. graf
Article in English | LILACS, BBO | ID: biblio-1090775

ABSTRACT

Abstract This study investigated the effect of a calcium hydroxide (CH) paste (CleaniCal®) containing N-2-methyl pyrrolidone (NMP) as a vehicle on Enterococcus faecalis (E. faecalis) biofilms compared with other products containing saline (Calasept Plus™) or propylene glycol (PG) (Calcipex II®). Methodology Standardized bovine root canal specimens were used. The antibacterial effects were measured by colony-forming unit counting. The thickness of bacterial microcolonies and exopolysaccharides was assessed using confocal laser scanning microscopy. Morphological features of the biofilms were observed using field-emission scanning electron microscopy (FE-SEM). Bovine tooth blocks covered with nail polish were immersed into the vehicles and dispelling was observed. The data were analyzed using one-way analysis of variance and Tukey tests (p<0.05). Results CleaniCal® showed the highest antibacterial activity, followed by Calcipex II® (p<0.05). Moreover, NMP showed a higher antibacterial effect compared with PG (p<0.05). The thickness of bacteria and EPS in the CleaniCal® group was significantly lower than that of other materials tested (p<0.05). FE-SEM images showed the specimens treated with Calasept Plus™ were covered with biofilms, whereas the specimens treated with other medicaments were not. Notably, the specimen treated with CleaniCal® was cleaner than the one treated with Calcipex II®. Furthermore, the nail polish on the bovine tooth block immersed in NMP was completely dispelled. Conclusions CleaniCal® performed better than Calasept Plus™ and Calcipex II® in the removal efficacy of E. faecalis biofilms. The results suggest the effect might be due to the potent dissolving effect of NMP on organic substances.


Subject(s)
Animals , Cattle , Pyrrolidinones/pharmacology , Root Canal Irrigants/pharmacology , Calcium Hydroxide/pharmacology , Enterococcus faecalis/drug effects , Biofilms/drug effects , Anti-Bacterial Agents/pharmacology , Potassium Chloride/pharmacology , Potassium Chloride/chemistry , Pyrrolidinones/chemistry , Root Canal Irrigants/chemistry , Materials Testing , Calcium Chloride/pharmacology , Calcium Chloride/chemistry , Calcium Hydroxide/chemistry , Microscopy, Electron, Scanning , Sodium Chloride/pharmacology , Sodium Chloride/chemistry , Colony Count, Microbial , Reproducibility of Results , Analysis of Variance , Sodium Bicarbonate/pharmacology , Sodium Bicarbonate/chemistry , Statistics, Nonparametric , Microscopy, Confocal , Drug Combinations
6.
J. appl. oral sci ; 27: e20180699, 2019. graf
Article in English | LILACS, BBO | ID: biblio-1012504

ABSTRACT

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.


Subject(s)
Animals , Cattle , Sodium Hypochlorite/pharmacology , DNA, Bacterial/pharmacology , Enterococcus faecalis/growth & development , Enterococcus faecalis/drug effects , Biofilms/growth & development , Biofilms/drug effects , Deoxyribonucleases/pharmacology , Polysaccharides, Bacterial/isolation & purification , Time Factors , Microscopy, Electron, Scanning , Colony Count, Microbial , Microbial Sensitivity Tests , Reproducibility of Results , Microscopy, Confocal , Dental Pulp Cavity/microbiology
7.
J. appl. oral sci ; 27: e20180157, 2019. tab, graf
Article in English | LILACS, BBO | ID: biblio-975884

ABSTRACT

Abstract Objectives The aim of this study was to evaluate the influence of surfactants 0.2% or 0.1% cetrimide (Cet) or 0.008% benzalkonium chloride (BAK) on 2.5% calcium hypochlorite (Ca(OCl)2), and compare to sodium hypochlorite (NaOCl), regarding the properties of pH, free chlorine content, surface tension, contact angle, pulp dissolution and antimicrobial activity. Material and Methods The pH and free chlorine content were evaluated by digital pHmeter and by titration, respectively. Surface tension was measured by the platinum ring technique with a Du Noüy tensiometer. The solution's contact angle in human dentin surfaces was checked by Drop Shape Analyzer software. Bovine pulps were used for pulp dissolution analysis and the dissolving capacity was expressed by percent weight loss. Antimicrobial activity over Enterococcus faecalis was evaluated by the agar diffusion method. Results Surfactants addition to Ca(OCl)2 and NaOCl did not alter the pH, free chlorine content and pulp dissolution properties. Ca(OCl)2 had the highest surface tension among all tested solutions. When surfactants were added to Ca(OCl)2 and NaOCl, there was a significant reduction of surface tension and contact angle values. The addition of 0.2% or 0.1% Cet enhanced antimicrobial activity of both Ca(OCl)2 and NaOCl. Conclusion Surfactant addition to 2.5% Ca(OCl)2 has shown acceptable outcomes for pH, free chlorine content, surface tension, contact angle, pulp dissolution and antimicrobial activity. Furthermore, the addition of 0.2% Cet showed better results for all tested properties.


Subject(s)
Humans , Animals , Cattle , Root Canal Irrigants/chemistry , Sodium Hypochlorite/chemistry , Surface-Active Agents/chemistry , Benzalkonium Compounds/chemistry , Calcium Compounds/chemistry , Cetrimonium/chemistry , Reference Values , Sodium Hypochlorite/pharmacology , Surface-Active Agents/pharmacology , Surface Properties , Benzalkonium Compounds/pharmacology , Materials Testing , Chlorine/analysis , Reproducibility of Results , Analysis of Variance , Enterococcus faecalis/drug effects , Calcium Compounds/pharmacology , Statistics, Nonparametric , Dental Pulp/drug effects , Dentin/drug effects , Cetrimonium/pharmacology , Hydrogen-Ion Concentration
8.
J. appl. oral sci ; 27: e20180183, 2019. tab, graf
Article in English | LILACS, BBO | ID: biblio-975880

ABSTRACT

Abstract Objectives: This study investigated the physical and mechanical properties, antibacterial effect and biocompatibility of novel elastomeric temporary resin-based filling materials (TFMs) containing zinc methacrylate (ZM). Material and Methods: Experimental TFMs were prepared by mixing the zinc methacrylate with monomer, co-monomer, photoinitiator and fillers. A ZM concentration of 0 (control), 0.5% (Z0.5); 1% (Z1), 2% (Z2), or 5% (ZM5) wt% was added to the TFMs. Fermit-N (F) was used for comparison with the experimental material. Microleakage, water sorption/solubility, degree of conversion, depth of cure, ultimate tensile strength, and hardness were determined and compared. A modified direct contact test (DCT) with Enterococcus faecalis and a Streptococcus mutans' biofilm accumulation assay was carried out to evaluate the antimicrobial effect and cytotoxicity of the assay. Statistical comparisons were performed (α=5%). Results: The results showed that the physical and mechanical properties of the experimental TFMs with ZM are comparable with the properties of the commercial reference and some properties were improved, such as lower microleakage and water sorption, and higher ultimate tensile strength values. TFMs with ZM killed E. faecalis only after 1 h. Biofilm development of S. mutans was not affected by the inclusion of ZM in the experimental TFMs. Conclusions: The present findings suggest that the physical, mechanical and biological properties of the experimental TFMs with ZM are comparable with the properties of the commercial reference. However, some properties were improved, such as lower microleakage and water sorption, and higher ultimate tensile strength values.


Subject(s)
Animals , Cattle , Zinc/chemistry , Composite Resins/chemistry , Elastomers/chemistry , Dental Restoration, Temporary/methods , Methacrylates/chemistry , Reference Values , Solubility , Streptococcus mutans/drug effects , Tensile Strength , Time Factors , Zinc/pharmacology , Materials Testing , Colony Count, Microbial , Random Allocation , Reproducibility of Results , Enterococcus faecalis/drug effects , Composite Resins/pharmacology , Elastomers/pharmacology , Dental Leakage , Hardness Tests , Methacrylates/pharmacology , Anti-Bacterial Agents/pharmacology
9.
Braz. j. biol ; 78(4): 619-624, Nov. 2018. tab, graf
Article in English | LILACS | ID: biblio-951603

ABSTRACT

Abstract Leaves and roots of Acanthospermum australe (Asteraceae) have been used in Brazilian folk medicine for the treatment of various ailments including diarrhea, skin diseases, blennorrhagia, dyspepsia, parasitic worms and malaria. The aim of study was to characterize the chemical profiles of the aqueous and hydroalcoholic extracts of leaves and roots of A. australe, and to evaluate their antimicrobial activities against diarrhea-inducing bacteria (Enterococcus faecalis, Shigella dysenteriae and Yersinia enterocolitica), as well as their cytotoxic properties. Aqueous leaf extracts were obtained by infusion, while aqueous root extracts were obtained by decoction. The hydroalcoholic leaf and root extracts were prepared by maceration in 90% ethanol for 3 days. Antimicrobial activity was assessed using standard techniques and cytotoxicity was evaluated using Chinese hamster ovary cells CHO-K1. Chemical analysis revealed the presence of tannins, flavonoids, saponins and phenolic compounds in the extracts. Although root extracts were not effective against E. faecalis, leaf extracts at concentrations of 20 mg/mL exhibited bactericidal activities against this microorganism. The hydroalcoholic root extract was unique in presenting a bactericidal effect against S. dysenteriae. None of the extracts showed bacteriostatic or bactericidal activities against Y. enterocolitica. The results presented herein demonstrate that the Gram-positive E. faecalis and the Gram-negative S. dysenteriae were susceptible to A. australe extracts, although bacteriostatic/bactericidal activities were only observed at concentrations considered too high for clinical application. Our results support the ethnopharmacological use of A. australe in the treatment of gastrointestinal disorders, particularly diarrhea caused by infectious bacteria, although further studies are required to determine the anti-diarrhea effects and the toxicities of the extracts in vivo.


Resumo Folhas e raízes de Acanthospermum australe (Asteraceae) têm sido usadas na medicina popular brasileira para o tratamento de várias doenças, incluindo diarreia, doenças de pele, blenorragia, dispepsia, vermes parasitas e malária. O objetivo deste estudo foi caracterizar os perfis químicos dos extratos aquosos e hidroalcoólicos das raízes e folhas de A. australe, e avaliar as suas atividades antimicrobianas contra as bactérias indutoras de diarreia (Enterococcus faecalis, Shigella dysenteriae e Yersinia enterocolitica), bem como sua citotoxicidade. Os extratos aquosos de folhas foram obtidos por infusão, enquanto que os extratos aquosos de raízes foram obtidos por decocção. Os extratos hidroalcoólicos de folhas e raízes foram preparados por maceração em etanol a 90% durante 3 dias. A atividade antimicrobiana foi avaliada utilizando técnicas padrão e a citotoxicidade foi avaliada utilizando células de ovário de hamster chinês CHO-K1. A análise química revelou a presença de taninos, flavonóides, saponinas e compostos fenólicos nos extratos. Apesar de extratos de raiz não foram eficazes contra E. faecalis, extratos de folhas em concentrações de 20 mg/mL apresentaram atividades bactericidas contra este microrganismo. O extrato hidroalcoólico de raiz foi o único a apresentar um efeito bactericida contra S. dysenteriae. Nenhum dos extratos apresentaram atividades bacteriostáticas ou bactericidas contra Y. enterocolitica. Os resultados apresentados demonstram que a bactéria Gram-positiva E. faecalis e a Gram-negativa S. dysenteriae foram suscetíveis aos extratos de A. australe, embora as atividades bacteriostáticos/bactericidas tenham sido apenas observados em concentrações consideradas elevadas para aplicação clínica. Os nossos resultados apoiam a utilização de etnofarmacológica de A. australe no tratamento de perturbações gastrointestinais, especialmente diarreia causadas por bactérias infecciosas, embora sejam necessários mais estudos para determinar os efeitos anti-diarreia e as toxicidades dos extratos in vivo.


Subject(s)
Shigella dysenteriae/drug effects , Yersinia enterocolitica/drug effects , Plant Extracts/pharmacology , Enterococcus faecalis/drug effects , Asteraceae/chemistry , Diarrhea/microbiology , Anti-Bacterial Agents/pharmacology , Plants, Medicinal , Brazil , Plant Extracts/chemistry , Microbial Sensitivity Tests , Toxicity Tests , Plant Roots/chemistry , Plant Leaves/chemistry , Medicine, Traditional
10.
Braz. dent. j ; 29(5): 459-464, Sept.-Oct. 2018. tab
Article in English | LILACS | ID: biblio-974175

ABSTRACT

Abstract The aim of this study was to compare the efficacy of grape seed extract (GSE), calcium hypochlorite [Ca(ClO)2], and sodium hypochlorite (NaOCl) irrigant solutions with rotary or reciprocating instrumentation for disinfection of root canals inoculated with Enterococcus faecalis. The mesiobuccal root canals of mandibular molars were prepared and inoculated with Enterococcus faecalis for 21 days. The roots were then randomly divided into the following eight experimental groups (n=11) according to the instrumentation technique and disinfection protocol: ProTaper Next or Reciproc R25 with sodium chloride (control group), 6% NaOCl, 6% Ca(ClO)2, or 50% GSE used for irrigation during instrumentation. The antimicrobial activity was determined on the basis of a reduction in colony-forming units (CFUs) counted on bacterial samples collected before and after root canal instrumentation and expressed as a percentage of reduction. Data were evaluated by two-way ANOVA followed by Tukey HSD post-hoc tests (p<0.05). No significant differences were observed in bacterial reduction between the ProTaper Next and Reciproc R25 systems (p>0.05), regardless of the irrigant solution used. Furthermore, all active solutions (6% NaOCl, 50% GSE, and 6% Ca(ClO)2) showed similar potential to reduce bacterial counts (p>0.05) and were significantly more effective than sodium chloride (control) (p<0.05). The results suggest that the GSE and Ca(ClO)2 have potential clinical application as irrigant solutions in endodontic therapy since they present bactericidal efficacy against Enterococcus faecalis.


Resumo O objetivo deste estudo foi comparar a eficácia do extrato de semente de uva (ESU), hipoclorito de cálcio [Ca(ClO)2] e hipoclorito de sódio (NaOCl) como soluções irrigadores quando utilizadas com instrumentos reciprocantes e rotatórios para desinfecção de canais radiculares infectados com Enterococcus faecalis. Raízes mesio-vestibulares de molares inferiores foram preparados e inoculados com E. faecalis por 21 dias. As raízes foram aleatoriamente divididas em 8 grupos (n=11) de acordo com a técnica de instrumentação e protocolo de irrigação: ProTaper Next ou Reciproc R25 associados com soro fisiológico (grupo controle), Ca(ClO)2 6%, NaOCl 6% ou ESU 50%. A atividade antimicrobiana foi determinada pela redução do número de Unidades Formadoras de Colonias (UFCs) coletadas antes e após a instrumentação e expressas em porcentagens de redução. Os dados foram analisados estatisticamente pelos testes ANOVA seguido pelo teste complementar de Tukey HSD (p<0,05). Não foi encontrado diferença estatisticamente significante na redução bacteriana entre os sistemas ProTaper Next e Reciproc R25 (p>0.05), independente da solução irrigadora usada. Além disso, todas as soluções ativas (NaOCl, ESU e Ca(ClO)2) mostraram similar potencial em reduzir a quantidade de bactérias (p>0.05) e foram significativamente mais efetivas que o soro fisiológico (p<0.05). Pode-se concluir que o ESU e o Ca(ClO)2 apresentam potencial para aplicação clínica como irrigantes endodônticos uma vez que apresentaram efetividade antimicrobiana contra o E. faecalis.


Subject(s)
Humans , Root Canal Irrigants/pharmacology , Disinfection/methods , Enterococcus faecalis/drug effects , Anti-Bacterial Agents/pharmacology , Sodium Hypochlorite/pharmacology , Stem Cells , In Vitro Techniques , Calcium Compounds/pharmacology , Composite Resins/chemistry , Dental Instruments , Dental Pulp Cavity/microbiology , Grape Seed Extract/pharmacology , Molar
11.
Braz. j. microbiol ; 49(1): 184-188, Jan.-Mar. 2018. tab, graf
Article in English | LILACS | ID: biblio-889206

ABSTRACT

ABSTRACT Removal of bacterial biofilm from the root canal system is essential for the management of endodontic disease. Here we evaluated the antibacterial effect of N-acetylcysteine (NAC), a potent antioxidant and mucolytic agent, against mature multispecies endodontic biofilms consisting of Actinomyces naeslundii, Lactobacillus salivarius, Streptococcus mutans and Enterococcus faecalis on sterile human dentin blocks. The biofilms were exposed to NAC (25, 50 and 100 mg/mL), saturated calcium hydroxide or 2% chlorhexidine solution for 7 days, then examined by scanning electron microscopy. The biofilm viability was measured by viable cell counts and ATP-bioluminescence assay. NAC showed greater efficacy in biofilm cell removal and killing than the other root canal medicaments. Furthermore, 100 mg/mL NAC disrupted the mature multispecies endodontic biofilms completely. These results demonstrate the potential use of NAC in root canal treatment.


Subject(s)
Humans , Acetylcysteine/pharmacology , Streptococcus mutans/drug effects , Actinomyces/drug effects , Enterococcus faecalis/drug effects , Biofilms/drug effects , Dental Pulp Diseases/microbiology , Lactobacillus salivarius/drug effects , Anti-Bacterial Agents/pharmacology , Streptococcus mutans/physiology , Actinomyces/physiology , Calcium Hydroxide/pharmacology , Chlorhexidine/pharmacology , Enterococcus faecalis/physiology , Dental Pulp Cavity/microbiology , Microbial Viability/drug effects , Lactobacillus salivarius/physiology
12.
An. acad. bras. ciênc ; 90(1): 73-84, Mar. 2018. tab
Article in English | LILACS | ID: biblio-886885

ABSTRACT

ABSTRACT The adhesion ability of bacteria to abiotic surfaces has important implications in food industries, because these organisms can survive for long periods through the biofilm formation. They can be transferred from one place to another in the industry causing contamination of the food processing environment. In this study, the antibacterial and antibiofilm activities of the antimicrobial peptide P34, characterized as a bacteriocin-like substance (BLS P34) were tested against planktonic and sessile cells of Staphylococcus aureus and Enterococcus faecalis isolated from foods. The BLS P34 showed inhibitory effect against all planktonic cells of E. faecalis. The inhibition of biofilm formation and the eradication of pre-formed biofilm were evaluated with the crystal violet assay and with the reduction of 3-bromide [4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium. The BLS P34 promoted a reduction of percentage of adhered microbial cells on the surface, not being able to perform the complete elimination of biofilm formation. The metabolic activity of S. aureus biofilms decreased considerably between 41-95%. However, E. faecalis cells showed up metabolically stimulated. The BLS P34 has the potential antibiofilm for the species S. aureus. Studies suggest more detailed approaches to a better understanding of the interactions between the antimicrobial and bacterial cells within the biofilm structure.


Subject(s)
Animals , Oligopeptides/pharmacology , Staphylococcus aureus/drug effects , Bacteriocins/pharmacology , Enterococcus faecalis/drug effects , Biofilms/drug effects , Anti-Bacterial Agents/pharmacology , Bacillus/isolation & purification , Bacillus/metabolism , Bacteriocins/isolation & purification , Bacterial Adhesion/drug effects , Microbial Sensitivity Tests , Analysis of Variance
13.
J. appl. oral sci ; 26: e20170562, 2018. tab, graf
Article in English | LILACS, BBO | ID: biblio-954492

ABSTRACT

Abstract The objective of this study was to compare selective physical-mechanical properties, antibacterial effects and cytotoxicity of seven temporary restorative materials (TRM): five resin-based materials [Bioplic (B), Fill Magic Tempo (FM), Fermit inlay (F), Luxatemp LC (L) and Revotek LC (R)], and zinc oxide-eugenol cement (IRM) and glass ionomer cement (GIC) as the controls. Material and methods The physical-mechanical properties were evaluated by determining microleakage (ML), ultimate tensile strength (UTS) and Shore D hardness (SDH). In addition, the polymerization rate (Pr-1), depth of cure (DC), water sorption and solubility (WS/SL) were evaluated. The antimicrobial effects of the materials were assessed by biofilm accumulation of Streptococcus mutans (BT) and the direct contact test (DCT) by exposure to Enterococcus faecalis for 1 and 24 h, and cytotoxicity by MTT assay. The data were analyzed by ANOVA or Kruskall-Wallis tests, and a complementary post-hoc method (p<0.05). Results Group B, followed by FM and GIC had significantly lower percentages of microleakage in comparison with the other groups; Groups FM and L showed the highest WS, while Groups R and FM showed the significantly lowest SL values (p<0.05). Group R showed the statistically highest UTS mean and the lowest DC mean among all groups. Group F showed the lowest S. mutans biofilm accumulation (p=0.023). Only the Group L showed continued effect against E. faecalis after 1 h and 24 h in DCT. The L showed statistically lower viability cell when compared to the other groups. Conclusions These findings suggest the antibacterial effect of the temporary materials Fill Magic and Bioplic against S. mutans, while Luxatemp showed in vitro inhibition of S. mutans biofilm accumulation and E. faecalis growth. Regarding the cell viability test, Luxatemp was the most cytotoxic and Fill Magic was shown to be the least cytotoxic.


Subject(s)
Animals , Cattle , Mice , Streptococcus mutans/drug effects , Enterococcus faecalis/drug effects , Composite Resins/pharmacology , Composite Resins/chemistry , Fibroblasts/drug effects , Anti-Bacterial Agents/blood , Anti-Bacterial Agents/pharmacology , Polymethacrylic Acids/pharmacology , Polymethacrylic Acids/chemistry , Root Canal Filling Materials/pharmacology , Root Canal Filling Materials/chemistry , Solubility , Tensile Strength , Time Factors , Zinc Oxide-Eugenol Cement/pharmacology , Zinc Oxide-Eugenol Cement/chemistry , Materials Testing , Cell Survival/drug effects , Reproducibility of Results , Bisphenol A-Glycidyl Methacrylate/pharmacology , Bisphenol A-Glycidyl Methacrylate/chemistry , Dental Restoration, Temporary/methods , Glass Ionomer Cements/pharmacology , Glass Ionomer Cements/chemistry , Hardness Tests , Methylmethacrylates/pharmacology , Methylmethacrylates/chemistry
14.
J. appl. oral sci ; 26: e20160608, 2018. graf
Article in English | LILACS, BBO | ID: biblio-954490

ABSTRACT

Abstract Objective Relacin is a synthetic molecule that targets RelA, an essential protein in a conserved bacterial stress response system. It was shown to inhibit bacterial growth. The aims of this study were to evaluate the antimicrobial effect of relacin combined with sodium hypochlorite (NaOCl) on Enterococcus faecalis biofilms and to evaluate the cytotoxicity of relacin. Material and Methods 48-h E. faecalis OG1RF biofilms were treated by various concentrations of relacin in order to determine its inhibitory concentration. Then, the 48-h biofilms were treated either with 1-min NaOCl (0.01%, 0.05%) alone, or in combination of relacin. As a means of comparison, the biofilms of ΔrelA were also treated by 1-min NaOCl (0.01%, 0.05%, 0.25%). The treatment efficacy was determined by agar plate count assays. The cytotoxicity of relacin was examined on human gingival epithelial cells Ca9-22 and murine fibroblasts NIH-3T3 by a methyl thiazolyltetrazolium (MTT) assay and a lactate dehydrogenase assay. Statistical analysis was performed by one-way or two-way analysis of variance (ANOVA) with Bonferroni's post-hoc test and an independent Student's t-test. A significance level of p<0.05 was used. Results Relacin inhibited the growth of OG1RF biofilms partially at 8 mM and fully at 14 mM. The relacin (14 mM) and NaOCl combined treatment resulted in significantly higher treatment efficacy than NaOCl treatment alone. At 0.05% NaOCl, the combined treatment resulted in 5.65 (±0.19) log reduction in biofilm viability. The ΔrelA biofilms were more susceptible to NaOCl treatment than the wild type biofilms at 0.25% NaOCl. Relacin at 14 mM was not toxic to host epithelial cells and fibroblasts. Conclusions The combination of relacin with a low concentration of NaOCl was effective and not cytotoxic.


Subject(s)
Humans , Animals , Sodium Hypochlorite/pharmacology , Enterococcus faecalis/drug effects , Biofilms/drug effects , Deoxyguanosine/analogs & derivatives , Dipeptides/pharmacology , Anti-Bacterial Agents/pharmacology , Tetrazolium Salts , Time Factors , Colony Count, Microbial , Microbial Sensitivity Tests , Reproducibility of Results , Analysis of Variance , Enterococcus faecalis/physiology , Biofilms/growth & development , NIH 3T3 Cells/drug effects , Deoxyguanosine/pharmacology , Epithelial Cells/drug effects , Formazans , Gingiva/cytology
15.
J. appl. oral sci ; 26: e20170374, 2018. tab
Article in English | LILACS, BBO | ID: biblio-893735

ABSTRACT

Abstract Objectives To determine the concentration of calcium, iron, manganese and zinc ions after the application of chelator to Enterococcus faecalis biofilms. Material and Methods Fifty bovine maxillary central incisors were prepared and inoculated with E. faecalis for 60 days. The following were used as irrigation solutions: 17% EDTA (pH 3, 7 and 10), 2.5% sodium hypochlorite (NaOCl) combined with 17% EDTA (pH 3, 7 and 10), distilled water (pH 3, 7 and 10), and 2.5% NaOCl. Each solution was kept in the root canal for five minutes. Fifteen uncontaminated root canals were irrigated with 17% EDTA (pH 3, 7 and 10). Six teeth were used as bacterial control. The number of calcium, iron, manganese and zinc ions was determined using flame atomic absorption spectrometry. Mean ± standard deviation (SD) values were used for descriptive statistics. Results Calcium chelation using 17% EDTA at pH 7 was higher than at pH 3 and 10, regardless of whether bacterial biofilm was present. The highest concentration of iron occurred at pH 3 in the presence of bacterial biofilm. The highest concentration of manganese found was 2.5% NaOCl and 17% EDTA at pH 7 in the presence of bacterial biofilm. Zinc levels were not detectable. Conclusions The pH of chelating agents affected the removal of calcium, iron, and manganese ions. The concentration of iron ions in root canals with bacterial biofilm was higher after the use of 17% EDTA at pH 3 than after the use of the other solutions at all pH levels.


Subject(s)
Animals , Cattle , Chelating Agents/pharmacology , Enterococcus faecalis/drug effects , Biofilms/drug effects , Dental Pulp Cavity/drug effects , Dental Pulp Cavity/microbiology , Root Canal Irrigants/pharmacology , Root Canal Irrigants/chemistry , Sodium Hypochlorite/pharmacology , Sodium Hypochlorite/chemistry , Spectrophotometry, Atomic , Materials Testing , Water/chemistry , Chelating Agents/chemistry , Calcium/analysis , Edetic Acid/pharmacology , Edetic Acid/chemistry , Enterococcus faecalis/chemistry , Dental Pulp Cavity/chemistry , Hydrogen-Ion Concentration , Ions , Iron/analysis , Manganese/analysis
16.
Braz. oral res. (Online) ; 32: e46, 2018. tab, graf
Article in English | LILACS | ID: biblio-889469

ABSTRACT

Abstract: The aim of this study was to evaluate the antimicrobial action of different endodontic pastes against Enterococcus faecalis ATCC 29212, isolated from the urinary tract, and compare the action with E. faecalis ATCC 4083, isolated from the root canal. For this purpose, dentin blocks were infected for 21 days with both bacteria at different time-intervals to ensure there would be no cross contamination. After this period, blocks were immersed in the test medications for 7 days, according to the following groups: CH/S, CH/P, CH/CMCP, CH/CHX, CH/DAP and TAP. Images of the samples were captured with a confocal microscope and the percentage of live cells was computed by means of the Bioimage program. The ATCC 29212 strain was shown to be more resistant to CH/SS, Calen, CH/DAP, and TAP than the ATCC 4083 strain. The antimicrobial action of the medications against each strain were divergent concerning the order of susceptibility. The authors concluded that the strains behaved in a different manner: in general, those extracted from the urinary tract were more resistant to the tested medications. Therefore, when E. faecalis must be used for in vitro research in endodontics, we suggest the use of ATCC 4083 strain to obtain results that are closer to the clinical reality.


Subject(s)
Animals , Cattle , Calcium Hydroxide/pharmacology , Chlorhexidine/pharmacology , Enterococcus faecalis/drug effects , Biofilms/drug effects , Dental Pulp Cavity/microbiology , Anti-Bacterial Agents/pharmacology , Microscopy, Electron, Scanning , Enterococcus faecalis/classification , Enterococcus faecalis/ultrastructure , Microscopy, Confocal , Biofilms/classification , Dental Pulp Cavity/ultrastructure
17.
J. appl. oral sci ; 25(6): 641-649, Nov.-Dec. 2017. tab, graf
Article in English | LILACS, BBO | ID: biblio-893677

ABSTRACT

Abstract The aim of this study was evaluate the influence of ultrasonic activation (UA) of AH Plus to improve canal and isthmus filing, and analyse the antimicrobial effect against Enterococcus faecalis within dentinal tubules. Material and Methods: Thirty mesial roots of mandibular first molars were selected and divided into 2 groups (n = 15): with and without UA of the sealer. Then the root canals were filled by using the single cone technique, and the specimens were sectioned at 2, 4 and 6 mm from the apex for stereomicroscope and confocal laser scanner microscopy (CLSM) analysis. In addition, 30 bovine incisors were contaminated with Enterococcus faecalis and divided into 3 groups (n = 10). The specimens were obturated by using the single cone technique with (G1) and without (G2) UA of the sealer and G3 as the control group. All were sectioned into 6 mm-long cylinders and stained with LIVE/DEAD to assess bacterial viability by CLSM. Results: The UA of the sealer significantly reduced the presence of unfilled areas in the canal and isthmus area in all sections (p<0.05), and there was a significant increase in sealer penetration in both canals and isthmuses (p<0.05). As regards gaps, a significant reduction was found at 2 and 6 mm in the isthmus area of the UA group (p<0.05). Moreover, UA of the sealer significantly reduced bacterial viability in the superficial dentine when compared with the other groups (p<0.05). Conclusion: Ultrasonic activation of the AH Plus sealer promoted a better quality of root canal filling and increased the intratubular penetration of sealer, especially in the isthmus area. Additionally, ultrasonic activation of the sealer increased the intradentinal antimicrobial action against Enterococcus faecalis, mainly in the superficial dentine of the root canal.


Subject(s)
Humans , Root Canal Filling Materials/pharmacology , Root Canal Obturation/methods , Ultrasonics , Enterococcus faecalis/drug effects , Dental Pulp Cavity/microbiology , Epoxy Resins , Microscopy, Confocal
18.
J. oral res. (Impresa) ; 6(12): 316-318, dic. 30, 2017. tab
Article in English | LILACS | ID: biblio-1118779

ABSTRACT

Objective: to compare the in vitro antibacterial effect of the root canal cements Endobalsam, Top Seal, Apexit and Endofill against enterococcus faecalis ATCC 29212. Materials and method: Eighty-five applications of cements on enterococcus faecalis, cultured in vitro on solid media in Petri dishes, were analyzed. five groups were evaluated: four for each cement, and the fifth for the positive control (amoxicillin). the antibacterial effect was measured by the diameters of the bacterial inhibition halos at 24 hours, 48 hours, and seven days. student´s t-test, ANOVA and the Tukey test were used for the statistical analysis. results: no statistically significant differences were found at 24 hours (p>0.05); at 48 hours and seven days, Endofill and Apexit had the greatest effect (p<0.05); finally, on day 7 only Endofill showed an effect similar to the positive control (p>0.05). conclusion: enterococcus faecalis ATCC 29212 was susceptible to all cements. Endofill had greater in vitro antibacterial effect than Apexit, Top Seal and Endobalsam.


Subject(s)
Root Canal Filling Materials/pharmacology , Gram-Positive Bacterial Infections , Enterococcus faecalis/drug effects , Dental Cements/pharmacology , Dental Pulp Cavity/microbiology , Peru , In Vitro Techniques , Treatment Outcome , Anti-Bacterial Agents
19.
Braz. dent. j ; 28(3): 372-379, May-June 2017. tab, graf
Article in English | LILACS | ID: biblio-888654

ABSTRACT

Abstract Psidium cattleianum (PC) has been displaying inhibitory effect against a variety of microorganisms, but this effect has not yet been tested against endodontic pathogens. The aim of this study was to evaluate the antimicrobial activity and biocompatibility of the aqueous (PCAE) and hydroethanolic (PCHE) extracts from Psidium cattleianum (PC) leaves. Minimum inhibitory concentration (MIC) and minimum lethal concentration (MLC) were determined using the microdilution broth method in order to analyze the antimicrobial effect against Enterococcus faecalis, Pseudomonas aeruginosa, Actinomyces israelii and Candida albicans in planktonic conditions. Biofilm assays were conducted only with the extracts that were able to determine the MLC for microorganisms in planktonic conditions. Immediate and late tissue reactions against PC extracts were evaluated using edemogenic test and histological analysis of subcutaneous implants in Wistar rats. The results showed that the MIC and MLC values ranged between 0.25 and 4 mg/mL. The MLC obtained for PCHE inhibited 100% growth of all the tested strains, except for C. albicans. PCAE had the same effect for E. faecalis and P. aeruginosa. Both PC extracts were able to eliminate E. faecalis biofilms and only the PCHE eliminated P. aeruginosa biofilms. The positive controls inhibited the growth of all tested strains in MIC and MLC essays, but no CHX tested concentrations were able to eliminate A. israelii biofilm. PCAE caused a discrete increase in the edema over time, while PCHE caused a higher initial edema, which decreased progressively. Both PCAE and PCHE extracts were biocompatible, but PCHE showed better results with slight levels of inflammation at 28 days. In conclusion, PCHE was biocompatible and presented better antimicrobial effect against important pathogens associated with persistent endodontic infections


Resumo Psidium cattleianum (PC) tem apresentado atividade inibitória frente diversos microrganismos, entretanto esse efeito ainda não foi testado contra microrganismos de interesse endodôntico. O objetivo desse estudo foi avaliar a atividade antimicrobiana e a biocompatibilidade dos extratos aquoso (EAPC) e hidroetanólico (EHPC) das folhas de Psidium cattleianum. As concentrações inibitória mínima (CIM) e letal mínima (CLM) foram determinadas pelo método de microdiluição em caldo, com o objetivo de analisar o efeito antimicrobiano frente Enterococcus faecalis, Pseudomonas aeruginosa, Actinomyces israelii e Candida albicans em condições planctônicas. Os ensaios de biofilme foram realizados somente com os extratos em que se determinou a CLM frente os microrganismos em condições planctônicas. Respostas teciduais imediata e tardia frente aos extratos de Psidium cattleianum foram avaliadas por teste edemogênico e análise histológica de implantes subcutâneos em ratos Wistar. Os resultados mostraram que CIM e CLM variaram entre 0,25 e 4 mg/mL. As CLMs determinadas pelo EHPC inibiram 100% do crescimento de todas as cepas testadas, exceto Candida albicans. EAPC apresentou o mesmo efeito para E. faecalis e P. aeruginosa. Ambos os extratos de PC conseguiram eliminar o biofilme de E. faecalis, e somente o EHPC eliminou o biofilme de P. aeruginosa. Os controles positivos inibiram o crescimento de todos os microrganismos testados nos ensaios de CIM e CLM, mas nenhuma das concentrações de clorexidina testadas foi capaz de eliminar o biofilme de A. israelii. O EAPC provocou um discreto aumento de edema com o tempo, enquanto EHPC provocou um edema inicial severo, que diminuiu progressivamente. Ambos os extratos EAPC e EHPC foram biocompatíveis, entretanto, EHPC apresentou melhores resultados com baixos níveis de inflamação em 28 dias. Pode-se concluir que EHPC foi biocompatível e apresentou melhor efeito antimicrobiano frente importantes patógenos associados a infecções endodônticas persistentes.


Subject(s)
Animals , Male , Anti-Infective Agents/pharmacology , Biocompatible Materials , Plant Extracts/pharmacology , Psidium/chemistry , Root Canal Therapy , Actinobacteria/drug effects , Biofilms , Candida albicans/drug effects , Enterococcus faecalis/drug effects , Microbial Sensitivity Tests , Pseudomonas aeruginosa/drug effects , Rats, Wistar
20.
Bauru; s.n; 2017. 118 p. ilus, tab.
Thesis in English | LILACS, BBO | ID: biblio-879689

ABSTRACT

When endodontic treatment fails, an alternative could be root canal retreatment. During this procedure, all filling material should be removed to allow a new root canal preparation and new obturation of the root canal system. Bacteria are the main cause of endodontic treatment failure, and persistent infection may be related to microorganism ability to penetrate into dentinal tubules. Therefore, this requires the use of irrigating solutions with antimicrobial action and low toxicity. The aim of this study was to evaluate the performance of instruments made of different alloys in root canal re-instrumentation during endodontic retreatment of lateral incisors with apical curvature, using computed microtomography and assessment of these samples by scanning electron microscopy after irrigant activation. Furthermore, the antimicrobial action of a root canal irrigant containing silver nanoparticles, 2% chlorhexidine and 2.5% sodium hypochlorite was evaluated against Enterococcus faecalis biofilm and dentin infected with this microorganism. Thirty extracted maxillary lateral incisors with apical curvature were selected. The teeth were instrumented, filled and divided into three different groups according to the protocol for removal of filling material: Group 1: re-instrumentation with Reciproc R25 instruments, Mtwo 40 and ProDesign Logic 50.01; Group 2: re-instrumentation with ProDesign R, ProDesign Logic 40 and ProDesign Logic 50.01; Group 3: re-instrumentation with Gates-Glidden drills and manual instruments K-file and Hedstroem files. For filling material removal analysis, the samples were scanned in a microtomograph device SkyScan 1174, for comparison of images taken before and after removing the root canal filling, and in each sample the volume was calculated at four levels (apical 1, apical 2, middle and cervical). These samples were split and analyzed by scanning electron microscopy to visualize filling material residues before and after irrigant activation with an ultrasonic device and with the EasyClean system used in continuous rotary motion. Statistical analyses were performed using Kruskal-Wallis, Friedman, Wilcoxon and Dunn tests. Furthermore, the minimum inhibitory concentration of an irrigating solution containing silver nanoparticles was determined against strains of Enterococcus faecalis, by using the microdilution method. Additionally, the antimicrobial activity of silver nanoparticle solution, 2% chlorhexidine and 2.5% sodium hypochlorite was tested against Enterococcus faecalis biofilm in vitro. For biofilm formation, bovine dentin blocks were placed in 24-well culture plates and Enterococcus faecalis biofilm was developed for 21 days. The dentin blocks were divided into 9 experimental groups of 5 blocks each, according to the irrigating solution used and the time in contact with the irrigant (5, 15 and 30 minutes). The samples were stained with Live/Dead reagent for analysis by confocal laser scanning microscopy (CLSM). Finally, the antimicrobial action of these solutions was tested after dentinal tubules were contaminated with Enterococcus faecalis. Dentin tubes were made from bovine incisors, taken to a centrifuge and infected with Enterococcus faecalis. The dentin tubes were treated with silver nanoparticle solution, 2% chlorhexidine and 2.5% sodium hypochlorite, and analyzed by CLSM to assess the antimicrobial activity of these solutions against bacteria in the dentinal tubules. The results showed that residues of filling material were found after root canal reinstrumentation in all groups. No significant difference was observed in removal of filling material between the reciprocating instruments Reciproc and ProDesign R and between rotary instruments Mtwo 40 and ProDesign Logic 40. The ProDesign Logic 50/.01 instrument significantly improved the removal of filling material compared with the use of Reciproc and ProDesign R instruments. The apical levels presented greater amount of remnant filling material compared with middle and cervical levels. After canal reinstrumentation, the passive ultrasonic irrigation and irrigant agitation with EasyClean significantly improved the removal of residual filling material in all root canal thirds. There was no significant difference between the performance of ultrasonics and EasyClean regarding the removal of residual filling material, as well no significant difference was observed in the removal of these residues when comparing apical, middle and cervical thirds. Regarding the action of the irrigating solutions against Enterococcus faecalis, the minimum inhibitory concentration of silver nanoparticle solution capable of eliminating this microorganism in broth and agar plates was 94 ppm. After the irrigation of Enterococcus faecalis biofilm, the silver nanoparticle solution was significantly less effective in killing bacteria compared with chlorhexidine when used for time of contact of 5 minutes. The sodium hypochlorite solution presented antimicrobial activity significantly higher compared with the silver nanoparticle solution and chlorhexidine. This solution also presented higher ability to dissolve biofilm in all times tested, whereas the silver nanoparticle solution presented higher ability to dissolve biofilm compared with chlorhexidine in times of 5 and 15 minutes. In infected intratubular dentin with Enterococcus faecalis, the sodium hypochlorite solution presented significant higher effectiveness than the silver nanoparticle solutions and chlorhexidine, especially in middle third and deep areas of the root canal. When comparing the antimicrobial activity of these solutions in biofilm and infected intratubular dentin, it was shown that when the silver nanoparticle solution was used for shorter periods of time, it was more effective in intratubular dentin compared with biofilm. On the other hand, with longer time of 30 minutes, the number of viable bacteria was higher in intratubular dentin than in biofilm, which was also observed when using the sodium hypochlorite solution in this time of action. It was concluded that to increase the rate of success in endodontic retreatment, the combination of the use of reciprocating and rotary instruments in the removal of filling material, the agitation of irrigants and the use of antimicrobial agents could be used in an attempt to eliminate bacteria that resisted to endodontic treatment. (AU)


Em casos de insucesso do tratamento endodôntico, uma alternativa seria o retratamento do canal radicular. Durante este procedimento deve haver remoção de todo o material obturador para que seja realizada novo preparo biomecânico e nova obturação do sistema de canais radiculares. Bactérias são o principal fator etiológico em casos de fracasso da terapia endodôntica, e esta infecção persistente pode estar relacionada à capacidade dos microganismos em penetrar nos túbulos dentinários. Por este motivo é necessário o uso de soluções na irrigação do canal radicular com ação antimicrobiana e com boa tolerância tecidual. O objetivo deste trabalho foi avaliar o desempenho dos instrumentos de diferentes ligas metálicas na desobturação do canal radicular durante o retratamento endodôntico de incisivos laterais superiores com curvatura apical, por meio da microtomografia computadorizada e análise destas amostras no microscópio eletrônico de varredura após a ativação de irrigantes. Posteriormente foi avaliada a capacidade antimicrobiana de um irrigante do canal radicular contendo nanopartículas de prata, clorexidina a 2% e hipoclorito de sódio a 2,5% frente ao biofilme de Enterococcus faecalis e à dentina contaminada com este mesmo microrganismo. Foram selecionados trinta incisivos laterais superiores humanos extraídos que apresentavam curvatura apical. Os dentes foram instrumentados, obturados e divididos em três diferentes grupos de acordo com o protocolo de remoção do material obturador do canal radicular: no Grupo 1: a desobturação foi realizada com os instrumentos Reciproc R25, Mtwo 40 e ProDesign Logic 50.01; no Grupo 2: foram utilizados os instrumentos ProDesign R, ProDesign Logic 40 e ProDesign Logic 50.01; e no Grupo 3: a desobturação foi realizada com brocas de Gates-Glidden e instrumentos manuais tipo K e Hedstroem. Para a análise da remoção do material obturador, as amostras foram escaneadas em micrótomogafo SkyScan 1174 para que fossem comparadas as imagens antes e após a desobturação do canal radicular, e em cada amostra este volume foi calculado nos quatro níveis (apical 1, 2, médio e cervical). Estas amostras posteriormente foram clivadas e analisadas no microscópio eletrônico de varredura, para a visualização de resíduos de material obturador antes e após a ativação de irrigantes com o ultrassom e com o sistema EasyClean utilizado em rotação contínua. Para a análise estatística dos resultados foram utilizados os testes de Kruskal-Wallis, Friedman, Wilcoxon e Dunn. Posteriormente, foi determinada a concentração inibitória mínima de uma solução irrigadora do canal contendo nanopartículas de prata frente a cepas de Enterococcus faecalis, através do método de diluição em caldo. Em seguida, foi testada a atividade antimicrobiana das soluções de nanopartículas de prata, da clorexidina a 2% e do hipoclorito de sódio a 2,5% sobre o biofilme de Enterococcus faecalis in vitro. Para isso, foram utilizados blocos de dentina bovina colocados em placas de 24 poços e biofilme de Enterococcus faecalis foi formado durante 21 dias. Os blocos de dentina foram divididos em 9 grupos experimentais com 5 blocos cada um, em função dos irrigantes avaliados e do tempo de exposição à solução irrigadora (5, 10 e 15 minutos). As amostras foram coradas com corante Live/Dead para posterior análise no microscópio confocal de varredura a laser (MCVL). Por fim, foi testada a atividade antimicrobiana destas soluções irrigadoras após a contaminação de túbulos dentinários com Enterococcus faecalis. Foram confeccionados tubos de dentina a partir de incisivos bovinos que foram levados à centrífuga e contaminados com Enterococcus faecalis. Os tubos de dentina receberam tratamento com a solução de nanopartículas de prata, com clorexidina a 2% e com hipoclorito de sódio a 2,5%, e foram analisados no MCVL para avaliar a atividade antimicrobiana das soluções sobre bactérias presentes nos túbulos dentinários. Os resultados demonstraram que resíduos de material obturador foram encontrados após a desobturação do canal em todos os grupos. Não houve diferença significante na remoção de material obturador entre os instrumentos reciprocantes Reciproc e ProDesign R e entre os instrumentos rotatórios Mtwo 40 e ProDesign Logic 40. O instrumento ProDesign Logic 50/.01 melhorou significantemente a remoção de material obturador comparado com o uso dos instrumentos Reciproc e ProDesign R. Os níveis apicais apresentaram uma maior quantidade de material obturador remanescente comparados com os níveis médio e cervical. Após a desobturação do canal radicular, a irrigação ultrassônica passiva e agitação dos irrigantes com o EasyClean melhoraram significantemente a remoção de resíduos de material obturador em todos os terços do canal radicular. Não houve diferença significante no desempenho do ultrassom e do EasyClean em relação à remoção de resíduos de material obturador, assim como não foi observada diferença significante na remoção destes resíduos quando comparados terços apical, médio e cervical. No que diz respeito à ação das soluções irrigadoras sobre o Enterococcus faecalis, a concentração inibitória mínima da solução de nanopartículas de prata capaz de eliminar este microrganimo em meio de cultura e ágar foi de 94 ppm. Após a irrigação no biofilme de Enterococcus faecalis, a solução de nanopartículas de prata foi significantemente menos efetiva em matar bactérias comparada com a clorexidina quando utilizadas pelo tempo de 5 minutos. A solução de hipoclorito de sódio apresentou atividade antimicrobiana significantemente maior comparada com as soluções de nanopartículas de prata e clorexidina. Essa solução ainda apresentou maior capacidade de dissolução do biofilme em todos os tempos testados, enquanto que a solução de nanopartículas de prata apresentou maior capacidade de dissolver o biofilme comparada à clorexidina nos tempos de 5 e 15 minutos. Na dentina intratubular infectada com Enterococcus faecalis, a solução de hipoclorito de sódio apresentou efetividade significantemente maior que as soluções de nanopartículas de prata e clorexidina, principalmente no terço médio e na região profunda do canal radicular. Quando comparada a atividade antimicrobiana destas soluções no biofilme e na dentina intratubular infectada, verificou-se que quando a solução de nanopartículas de prata foi utilizada por um tempo mais curto, foi mais efetiva na dentina intratubular comparada com o biofilme. De maneira contrária, com tempo maior de 30 minutos, o número e bactérias viáveis foi maior na dentina intratubular do que no biofilme, o que ocorreu também com a solução de hipoclorito de sódio neste tempo de ação. Conclui-se que para se aumentar a chance de sucesso em tratamentos retratamentos endodônticos, a combinação do uso de instrumentos reciprocantes e rotatórios na desobturação do canal, agitação de irrigantes e uso de agentes com capacidade antimicrobiana podem ser utilizados na tentativa de se eliminar bactérias resistente ao tratamento endodôntico. (AU)


Subject(s)
Humans , Chlorhexidine/pharmacology , Enterococcus faecalis/drug effects , Metal Nanoparticles/chemistry , Root Canal Irrigants/pharmacology , Root Canal Obturation/methods , Sodium Hypochlorite/pharmacology , Anti-Infective Agents/pharmacology , Biofilms/drug effects , Dental Pulp Cavity/microbiology , Materials Testing , Microscopy, Electron, Scanning , Reproducibility of Results , Retreatment/methods , Root Canal Obturation/instrumentation , X-Ray Microtomography
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