Prevalence of treponema Spp. in endodontic retreatment-resistant periapical lesions

This study investigated the presence of the Treponema species in longstanding endodontic retreatment-resistant lesions of teeth with apical periodontitis, the association of this species with clinical/radiographic features, and the association among the different target species. Microbial samples of apical lesions were collected from twenty-five adult patients referred to endodontic surgery after unsuccessful root canal retreatment. Nested-PCR and conventional PCR were used for Treponema detection. Twenty-three periradicular tissue samples showed detectable levels of bacterial DNA. Treponema species were detected in 28% (7/25) of the cases. The most frequently detected species were T. socranskii (6/25), followed by T. maltophilum (3/25), T. amylovorum (3/25), T. lecithinolyticum (3/25), T. denticola (3/25), T. pectinovorum (2/25) and T. medium (2/25). T. vicentii was not detected in any sample. Positive statistical association was found between T. socranskii and T. denticola, and between T. maltophilum and T. lecithinolyticum. No association was detected between the presence of any target microorganism and the clinical or radiographic features. Treponema spp. are present, in a low percentage, in longstanding apical lesions from teeth with endodontic retreatment failure291CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES302575/2009-0sem informaçã

Evaluation of cytotoxicity, antimicrobial activity and physicochemical properties of a calcium aluminate-based endodontic material

A calcium aluminate-based endodontic material, EndoBinder, has been developed in order to reduce MTA negative characteristics, preserving its biological properties and clinical applications. Objectives: The aim of this study was to evaluate the cytotoxicity, antimicrobial activity, pH, solubility and water sorption of EndoBinder and to compare them with those of white MTA (WMTA). Material and Methods: Cytotoxicity was assessed through a multiparametric analysis employing 3T3 cells. Antimicrobial activity against Enterococcus faecalis (ATCC 29212), Staphylococcus aureus. (ATCC 25923) and Candida albicans (ATCC 10556) was determined by the agar diffusion method. pH was measured at periods of 3, 24, 72 and 168 hours. Solubility and water sorption evaluation were performed following ISO requirements. Data were statistically analyzed by ANOVA and Tukey's test with a significance level of 5%. Results: EndoBinder and WMTA were non-cytotoxic in all tested periods and with the different cell viability parameters. There was no statistical differences between both materials (P>.05). All tested materials were inhibitory by direct contact against all microbial strains tested. EndoBinder and WMTA presented alkaline pH in all tested times with higher values of pH for WMTA (P.05). Conclusion: Under these experimental conditions, we concluded that the calcium aluminate-based endodontic material EndoBinder demonstrated suitable biological and physicochemical properties, so it can be suggested as a material of choice in root resorption, perforations and root-end filling221616

Evaluation of cytotoxicity, antimicrobial activity and physicochemical properties of a calcium aluminate-based endodontic material

A calcium aluminate-based endodontic material, EndoBinder, has been developed in order to reduce MTA negative characteristics, preserving its biological properties and clinical applications. Objectives: The aim of this study was to evaluate the cytotoxicity, antimicrobial activity, pH, solubility and water sorption of EndoBinder and to compare them with those of white MTA (WMTA). Material and Methods: Cytotoxicity was assessed through a multiparametric analysis employing 3T3 cells. Antimicrobial activity against Enterococcus faecalis (ATCC 29212), Staphylococcus aureus. (ATCC 25923) and Candida albicans (ATCC 10556) was determined by the agar diffusion method. pH was measured at periods of 3, 24, 72 and 168 hours. Solubility and water sorption evaluation were performed following ISO requirements. Data were statistically analyzed by ANOVA and Tukey`s test with a significance level of 5%. Results: EndoBinder and WMTA were non-cytotoxic in all tested periods and with the different cell viability parameters. There was no statistical differences between both materials (P>;.05). All tested materials were inhibitory by direct contact against all microbial strains tested. EndoBinder and WMTA presented alkaline pH in all tested times with higher values of pH for WMTA (

Periostin Responds to Mechanical Stress and Tension by Activating the MTOR Signaling Pathway

Current knowledge about Periostin biology has expanded from its recognized functions in embryogenesis and bone metabolism to its roles in tissue repair and remodeling and its clinical implications in cancer. Emerging evidence suggests that Periostin plays a critical role in the mechanism of wound healing; however, the paracrine effect of Periostin in epithelial cell biology is still poorly understood. We found that epithelial cells are capable of producing endogenous Periostin that, unlike mesenchymal cell, cannot be secreted. Epithelial cells responded to Periostin paracrine stimuli by enhancing cellular migration and proliferation and by activating the mTOR signaling pathway. Interestingly, biomechanical stimulation of epithelial cells, which simulates tension forces that occur during initial steps of tissue healing, induced Periostin production and mTOR activation. The molecular association of Periostin and mTOR signaling was further dissected by administering rapamycin, a selective pharmacological inhibitor of mTOR, and by disruption of Raptor and Rictor scaffold proteins implicated in the regulation of mTORC1 and mTORC2 complex assembly. Both strategies resulted in ablation of Periostin-induced mitogenic and migratory activity. These results indicate that Periostin-induced epithelial migration and proliferation requires mTOR signaling. Collectively, our findings identify Periostin as a mechanical stress responsive molecule that is primarily secreted by fibroblasts during wound healing and expressed endogenously in epithelial cells resulting in the control of cellular physiology through a mechanism mediated by the mTOR signaling cascade.This work was funded by the National Institutes of Health (NIH/NCI) P50-CA97248 (University of Michigan Head and Neck SPORE)

Analise microbiologica e suscetibilidade antimicrobiana de alguns microrganismos isolados de canais radiculares infectados associados a lesões periapicais

Orientador : Brenda Paula Figueiredo de Almeida GomesDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: O objetivo deste estudo foi analisar a microbiota de canais radiculares infectados e com lesão periapical de dentes sintomáticos e assintomáticos; correlacionar a presença de bactérias específicas com a sintomatologia endodôntica e investigar a suscetibilidade antimicrobiana de bactérias anaeróbias Gram-negativas isoladas dos canais de dentes sintomáticos com lesão periapical contra 8 antibióticos usando o E-test. Amostras microbiológicas foram coletadas de 48 canais radiculares com polpa necrosada, 29 com dor espontânea e 19 sem dor espontânea no momento da coleta, usando técnicas microbiológicas adequadas. Um total de 218 isolados clínicos foi encontrado, os quais pertenciam a 48 diferentes espécies e 19 diferentes gêneros. Canais radiculares de dentes sintomáticos apresentaram uma predominância de anaeróbios estritos e um número maior de espécies por canal radicular em relação aos dentes assintomáticos. Mais de 70% do total das bactérias isoladas eram anaeróbias estritas. Análise estatística foi feita através dos testes X2 de Person ou de Fisher. Associações foram encontradas entre grupos microbianos específicos, principalmente anaeróbios Gram-negativos e a presença de dor espontânea ou dor prévia, dor à percussão, dor à palpação e edema. Amoxicilina, amoxicilina + ácido c1avulânico e cefac1or foram efetivos contra todas as cepas testadas. A menor taxa de suscetibilidade foi apresentada por Prevotella intermedia/nigrescens contra penicilina G. Nossos resultados sugerem que bactérias específicas estão associadas aos sinais e sintomas endodônticos de dentes com canais contaminados e lesão periapical e que, a maioria das espécies Gram-negativas testadas foram sensíveis aos antibióticos estudadosAbstract: The aim of this study was to analyse the microflora isolated ITom infected root canals of symptomatic or asymptomatic teeth, to correlate the presence of specific bacteria with endodontic symptomatology and to investigate the antibiotic susceptibility of the anaerobic Gram-negative bacteria isolated ITom symptomatic teeth with periapicallesions against 8 antibiotics through the E-test. Microbial samples were taken ITom root canals of 48 teeth with necrotic dental pulp, 29 symptomatic and 19 asymptomatic, using adequate techniques. A total of 218 cultivable isolates were recovered ITom 48 different microbial species and 19 different genera. Root canals ITom symptomatic teeth harboured more obligate anaerobes and a bigger number of bacterial species than the asymptomatic teeth. More than 70% ofthe total bacterial isolates were strict anaerobes. Statistical analysis used a Pearson r test or a one-sided Fisher' s Exact test, as appropriate. Relationships were found between specific microorganisms, especially Gram-negative anaerobes and the presence of pain or histol)' ofpain, tendemess to percussion, pain to palpation and swelling. Amoxicillin, amoxicillin + clavulanate and cephaclor were efIective against all the strains tested. The lowest susceptibility rate was presented by Prevotella intermedia/nigrescens against penicillin G. Our results suggested that specific bacteria are associated with endodontic symptoms of infected teeth and the majority of the Gram-negative bacterial species tested were susceptible to all antibiotics studied.MestradoEndodontiaMestre em Clínica Odontológic

Association of endodontic symptoms with specific microorganisms and endotoxin from infected root canals and antimicrobial susceptibility testing of strict anerobic bacteria isolated.

Orientador: Brenda Paula Figueiredo de Almeida GomesTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: Os objetivos deste estudo foram analisar a microbiota de canais radiculares com necrose e com lesão periapical de dentes sintomáticos e assintomáticos; quantificar a presença de endotoxinas; correlacionar a presença de bactérias específicas e a quantidade de endotoxinas com os sinais e sintomas de origem endodôntica; e investigar a suscetibilidade antimicrobiana de bactérias anaeróbias estritas isoladas dos canais radiculares contra 8 antibióticos, usando o E-test. Amostras microbiológicas foram coletadas de 90 canais radiculares com polpa necrosada e processadas por meio de técnicas microbiológicas. Outras 50 amostras foram obtidas de canais radiculares necrosados, sintomáticos e assintomáticos para realização do teste cromogênico para quantificação das endotoxinas. Análise estatística foi feita pelos testes x2 de Person ou de Fisher. Um total de 400 isolados clínicos foi encontrado, os quais pertenciam a 69 diferentes espécies e 22 diferentes gêneros. Oitenta por cento das bactérias eram anaeróbias estritas e F. nucleatum foi a espécie predominante. Canais radiculares de dentes sintomáticos apresentaram uma predominância de anaeróbios estritos e um número maior de espécies por canal radicular em relação aos dentes assintomáticos. Foi observada uma relação entre grupos microbianos específicos, principalmente anaeróbios Gram-negativos e a presença de dor espontânea ou dor prévia, dor à percussão, dor à palpação e edema. Endotoxinas foram encontradas em altas concentrações em canais radiculares de dentes sintomáticos e houve uma correlação positiva entre os sinais e sintomas e a concentração de endotoxinas. Amoxicilina, amoxicilina associada ao ácido clavulânico e cefaclor foram efetivos contra todas as cepas testadas. Os resultados sugerem que bactérias específicas e endotoxinas estão associadas aos sinais e sintomas de dentes com canais infectados e lesão periapical e que, a maioria das espécies anaeróbias testadas foi suscetível aos antibióticos estudadosAbstract: The aim of this study was to analyse the microflora isolated from infected root canals of symptomatic or asymptomatic teeth, to quantify the presence of endotoxins; to correlate the presence of specific bacteria and the amount of endotoxins with endodontic symptomatology; and to investigate the antibiotic susceptibility of anaerobic bacteria isolated from infected teeth with periapical lesions against 8 antibiotics through the E-test. Microbial samples were taken from 90 root canals of teeth with necrotic dental pulp, and analysed using rigorous culture procedures. Other 50 samples were collected from infected symptomatic or asymptomatic root canals in order to be analysed by a chromogenic test for the endotoxin quantification. Statistical analysis used a Pearson x2 test or a one-sided Fisher's Exact test, as appropriate. A total of 400 cultivable isolates were recovered from 69 different microbial species and 22 different genera. Eight per cent of the bacteria were were strict anaerobes and F. nucleatum was the most frequently isolated species. Root canals from symptomatic teeth harboured more obligate anaerobes and a larger number of bacterial species than the asymptomatic teeth. Relationships were found between specific microorganisms, especially Gram-negative anaerobes and the presence of pain or history of pain, tenderness to percussion, pain to palpation and swelling. High concentrations of endotoxins were found in root canals of symptomatic teeth and there was a positive correlation between endodontic signs and symptoms and the concentration of endotoxins in infected root canals. Amoxicillin, amoxicillin + clavulanate and cephaclor were effective against all the strains tested. Our results suggested that specific bacteria and endotoxins are associated with endodontic symptoms of infected teeth and that the majority of the anaerobic species tested was susceptible to all antibiotics studied.DoutoradoEndodontiaDoutor em Clínica Odontológic

Evaluation of cytotoxicity, antimicrobial activity and physicochemical properties of a calcium aluminate-based endodontic material

A calcium aluminate-based endodontic material, EndoBinder, has been developed in order to reduce MTA negative characteristics, preserving its biological properties and clinical applications. Objectives: The aim of this study was to evaluate the cytotoxicity, antimicrobial activity, pH, solubility and water sorption of EndoBinder and to compare them with those of white MTA (WMTA). Material and Methods: Cytotoxicity was assessed through a multiparametric analysis employing 3T3 cells. Antimicrobial activity against Enterococcus faecalis (ATCC 29212), Staphylococcus aureus. (ATCC 25923) and Candida albicans (ATCC 10556) was determined by the agar diffusion method. pH was measured at periods of 3, 24, 72 and 168 hours. Solubility and water sorption evaluation were performed following ISO requirements. Data were statistically analyzed by ANOVA and Tukey`s test with a significance level of 5%. Results: EndoBinder and WMTA were non-cytotoxic in all tested periods and with the different cell viability parameters. There was no statistical differences between both materials (P>.05). All tested materials were inhibitory by direct contact against all microbial strains tested. EndoBinder and WMTA presented alkaline pH in all tested times with higher values of pH for WMTA (P<.05). Both materials showed values complying with the solubility minimum requirements. However, EndoBinder showed lower solubility than WMTA (P<.05). No statistical differences were observed regarding water sorption (P>.05). Conclusion: Under these experimental conditions, we concluded that the calcium aluminate-based endodontic material EndoBinder demonstrated suitable biological and physicochemical properties, so it can be suggested as a material of choice in root resorption, perforations and root-end filling

Tissue reaction to Aroeira (Myracrodruon urundeuva) extracts associated with microorganisms: an in vivo study

<div><p>Abstract: Based on aroeira's (Myracrodruon urundeuva) antimicrobial activity and a future trend to compose intracanal medication, the aim of this study was to assess in vivo inflamatory tissue response to the extracts by edemogenic and histological analysis containing inactivated facultative and anaerobic microorganisms. For edema quantification, eighteen animals were divided into three groups (n = 3, periods: 3 and 6 hours) and 0.2 mL of 1% Evans blue per 100 g of body weight was injected into the penile vein under general anesthesia. After 30 min the animals received a subcutaneous injection in the dorsal region of aqueous or ethanolic extract of aroeira or saline (control) containing inactivated bacteria. Samples were collected, immersed in formamide for 72h, and evaluated by spectrophotometry (630 m). For histological analysis, polyethylene tubes with the extracts were implanted in the dorsal of 30 male rats. Analysis of the fibrous capsule and inflammatory infiltrate were performed after 7 and 30 days. The aqueous extract group induced less edema in both postoperative periods compared to the other groups, but the differences were not significant (p > 0.05). Tissue repair was significantly better after 30 days than after 7 days (p < 0.01). The aqueous solution showed less inflammatory response than the ethanolic solution (p < 0.05), with tendency for better results than control after 7 days. After 30 days, the response to both extracts was similar to control. The aqueous and ethanolic aroeira extracts containing inactivated microorganisms showed a trend for better results than saline, even when associated with microorganisms, and facilitated the tissue repair process.</p></div