Abstract: Accumulated hard tissue debris (AHTD) in root canal irregularities may negatively impact adequate root canal disinfection. In light of this, the efficacy of passive ultrasonic irrigation (PUI) to reduce AHTD has been largely studied in in vitro studies, which have adopted different analytic methods of varying accuracy to determine the extent of AHTD more correctly. Therefore, the aim of this study was to compare how well PUI and non-activated irrigation (NAI) systems perform in reducing AHTD during final irrigation protocols, based exclusively on studies whose analyses used microCT scanning. A systematic search of the studies published up to April 2020 was performed using MeSH terms and free terms, in the following databases: PubMed, Scopus, Web of Science, BVS (Lilacs and BBO) and Embase. The inclusion criteria consisted of laboratory studies that evaluated the amount of AHTD, and compared PUI with NAI protocols using microCT analysis. The risk of bias in the selected studies was assessed critically by two reviewers. A meta-analysis was performed using the RevMan software program (P<0.05), and included studies providing the standardized mean difference (SMD), using a fixed effect model, and adopting a confidence interval of 95%. In all, 3495 studies were identified, three of which met the inclusion criteria. All three were considered as having a low risk of bias. The meta-analysis comparing the ability of PUI and NAI protocols to remove hard tissue debris showed a higher percentage of AHTD reduction (P<0.01) for PUI, with a confidence interval of 1.41 [0.79, 2.02]. The heterogeneity among the studies was 82% (I2). Considering the limitations of the present study, this systematic review and meta-analysis showed that PUI was more effective than NAI in removing hard tissue debris, based exclusively on studies that used microCT scanning to provide a more precise analysis of the two techniques used. The findings presented in the present study reinforce the concept that PUI can increase residue removal and improve the cleanliness of the root canal in endodontic treatments.

Resumo Esse estudo investigou a resistência de união de dois cimentos endodônticos experimentais à base de MTA e butiletilenoglicol dissalicilato: MTAe e MTAe. Os materiais de referência utilizados para comparação foram os cimentos endodônticos MTA Fillapex e AH Plus. Vinte incisivos superiores humanos foram selecionados e um slice dentinário de 1 mm de espessura foi obtido do terço cervical de cada raiz. Na superfície coronária de cada slice, quatro orifícios com 0,9 mm de diâmetro foram confeccionados através da dentina. Uma irrigação padronizada foi realizada e os orifícios foram preenchidos com um dos quatro cimentos endodônticos avaliados: AH Plus, MTA Fillapex, MTAe, e MTAe-HA. Os slices preenchidos foram armazenados em solução PBS (pH 7,2) durante 7 dias a 37°C. O ensaio de push-out foi realizado por meio de um dispositivo com 0,7 mm de diâmetro. A carga foi aplicada com a velocidade de 0,5 mm/min até a obtenção de deslocamento do material obturador. Os resultados foram expressos em MPa. O teste de Kruskal-Wallis foi aplicado para avaliar o efeito da resistência de união de cada cimento endodôntico. O teste de Mann-Whitney com correção de Bonferroni foi utilizado para isolamento das diferenças. O erro do tipo-alfa foi fixado em 0,05. Diferenças significantes entre os valores de medianas obtidos pelos materiais foram observados (p<0,001). O AH Plus demonstrou os maiores valores de resistência de união (p<0,001). Em contraste, o MTA Fillapex apresentou a menor resistência de união entre todos os cimentos testados (p<0,001). Os cimentos experimentais demonstraram valores intermediários, com ausência de diferenças estatísticas entre si (p>0,05). Em conclusão, os cimentos endodônticos experimentais à base de MTA e butiletilenoglicol dissalicilato apresentaram resultados adequados de resistência de união quando comparados ao MTA Fillapex.

Abstract This study investigated the bond strength of two experimental root canal sealers based on MTA and butyl ethylene glycol disalicylate: MTAe and MTAe-HA. The reference materials used for comparison were AH Plus and MTA Fillapex. Twenty human upper incisors were selected and one 1 mm slice was obtained from the cervical third of each root. On the coronal surface of each slice, four 0.9 mm wide holes were drilled through the dentine. Standardized irrigation was performed and holes were filled with one of the four tested sealers: AH Plus, MTA Fillapex, MTAe, and MTAe-HA. The filled slices were stored in a PBS solution (pH 7.2) for 7 days at 37 °C. A push-out assessment was performed with a 0.7 mm plunger tip. Load was applied at a crosshead speed of 0.5 mm/min until sealer displacement. The results were expressed in MPa. The Kruskal-Wallis test was applied to assess the effect of each sealer on the push-out bond strength. Mann-Whitney with Bonferroni correction was used to isolate the differences. The alpha-type error was set at 0.05. Significant differences among medians values obtained by materials were observed (p<0.001). AH Plus displayed the highest value of bond strength (p<0.001). In contrast, MTA Fillapex presented the lowest bond strength among all tested sealers (p<0.001). Experimental sealers showed intermediary bond strength values, with no statistical differences between them (p>0.05). In conclusion, experimental root canal sealers presented suitable bond strength outcomes when compared to MTA Fillapex.

The present study aimed to assess the prevalence of apical periodontitis (AP) in an urban Brazilian population according to gender, age group and tooth type. Data were collected from clinical files containing the medical and dental histories and periapical radiographs of 1,126 patients treated at the School of Dentistry at Universidade do Estado do Rio de Janeiro between March 2000 and December 2010. A total of 15,724 periapical radiographs were evaluated. All the radiographs were evaluated by two independent, previously calibrated endodontists (kappa = 0.88). Periapical areas on the radiographs were classified as N (normal) or AR (apical radiolucency). The frequency of AP and the 95% Confidence Interval (95%CI) were calculated according to gender, age group and tooth type. Differences between groups were calculated using the Z-test at a significance level of 5% (p < 0.05). AP was present in 7.87% of the samples, with 16.70% occurring on previously endodontically treated teeth and 44.65% occurring on teeth referred for endodontic treatment (TR-RCT). The frequency of AP was higher among females (64%) than among males (35%). The central and lateral maxillary incisors were the most frequently affected teeth. The frequency of AP was higher among individuals between 30 and 49 years of age. In this population, AP was more prevalent among females and among individuals between 30 and 49 years of age, and the central and lateral maxillary incisors were the most frequently affected teeth.

O objetivo do presente estudo foi avaliar a capacidade de alguns irrigantes endodônticos em induzir danos genéticos e/ou morte celular in vitro. Células de fibroblastos murinos foram expostas ao ácido etilenodiaminotetracético (EDTA), hipoclorito de sódio (NaOCl), MTAD™ e ácido cítrico em concentrações crescentes durante 3 h a 37°C. O grupo controle negativo foi tratado com solução tampão fosfato - PBS por 3 h a 37° C e o grupo controle positivo foi tratado com metilmetanesulfonato a 1 μM por 3 h a 37° C. A citotoxicidade foi testada pelo azul de tripan e a genotoxicidade foi avaliada pelo teste do cometa. Os resultados apontaram que a exposição ao NaOCl a 2,5% e 5%, e ácido cítrico a 21% resultou em efeitos citotóxicos significativos. O NaOCl, EDTA e o ácido cítrico não produziram efeitos genotóxicos no que diz respeito aos dados obtidos pelo ensaio do Cometa em todas as concentrações testadas. Embora o MTAD não tenha sido um agente citotóxico, mostrou efeitos genotóxicos significativos em todas as concentrações testadas (ANOVA e teste de Tuckey; p<0,05). O NaOCl, o EDTA e o ácido cítrico mostraram-se citotóxicos de maneira dose-dependente, mas não genotóxicos. Por outro lado, apesar do MTAD não ter causado a morte celular, foi genotóxico em todas as concentrações testadas.

The aim of the present study was to evaluate the capacity of some root canal irrigants to induce genetic damage and/or cellular death in vitro. Murine fibroblast cells were exposed to ethylenediaminetetraacetic acid (EDTA), sodium hypochlorite (NaOCl), MTAD™ and citric acid in increasing concentrations for 3 h at 37ºC. The negative control group was treated with vehicle control (phosphate buffer solution - PBS) for 3 h at 37°C, and the positive control group was treated with methylmetanesulfonate, 1 μM. for 3 h at 37°C. Cytotoxicity was assessed by the trypan blue test and genotoxicity was evaluated by the single cell gel (comet) assay. The results showed that exposure to 2.5% and 5% NaOCl and 8.5% citric acid resulted in a significant cytotoxic effect. NaOCl, EDTA and citric acid did not produce genotoxic effects with respect to the comet assay data for all evaluated concentrations. Although MTAD was not a cytotoxic agent, it showed significant genotoxic effects at all tested concentrations (ANOVA and Tukey's test; p<0.05). NaOCl, EDTA and citric acid were found to be cytotoxic in a dose-dependent manner, but they were not genotoxic. MTAD did not cause cell death, but presented genotoxic effects.

Este relato de caso apresenta os procedimentos clínicos envolvidos no tratamento de um caso de fratura corono-radicular complicada de um incisivo superior esquerdo com ápice aberto de um paciente de 10 anos de idade devido à queda da própria altura. O tratamento envolveu pulpotomia cervical e fixação do fragmento. Após 1 ano, os exames clínicos e radiográficos demonstraram necrose pulpar e lesão perirradicular associada. O tratamento endodôntico foi realizado com a utilização de pasta de hidróxido de cálcio, obturação endodôntica e extrusão ortodôntica. Após aproximadamente 16 semanas, o processo de extrusão foi finalizado e o dente restaurado com pino e coroa protética. Após acompanhamento de 3 anos, não havia evidência de lesão perirradicular e o dente estava estética e funcionalmente satisfatório.

This report describes the clinical procedures involved in the treatment of a complicated crown-root fracture in the maxillary left central incisor with a wide open apex of a 10-year-old male patient, due to fall from his own height. Post-trauma treatment comprised cervical pulpotomy and adhesive tooth fragment reattachment. After 1 year, clinical and radiograph examinations showed pulp necrosis and an associated periapical lesion. Endodontic therapy with calcium hydroxide-base intracanal dressing, root canal filling and orthodontic extrusion were performed. Extrusion was completed within approximately 16 weeks and the tooth was restored with a post-core system and a prosthetic crown. After a 3 years of follow-up, there was no evidence of apical periodontitis and the tooth was satisfactory both esthetically and functionally.

Este estudo in vitro avaliou, por um modelo de infiltração bacteriano, se a medicação intracanal com hidróxido de cálcio associado a diferentes veículos, tem efeito inibitório na penetração coronária de bactéria. Quarenta caninos humanos instrumentados foram medicados com Ca(OH)2 p.a. associados à G1= água destilada; G2= polietilenoglicol (PG); G3= polietilenoglicol e paramonoclorofenol canforado (PMCP); e G4= glicerina. Cinco dentes hígidos foram utilizados como grupo controle negativo e cinco dentes instrumentados sem medicação intracanal serviram como grupo controle positivo. Todos os dentes foram montados em um aparato de duas câmaras e expostos a saliva humana por 63 dias. A infiltração foi verificada através da observação do turvamento do meio de cultura na câmara inferior. Cinqüenta por cento das amostras do G1 e G2, 10% do G3 e 80% do G4 foram totalmente contaminadas após 9 semanas. Diferenças estatisticamente significantes foram observadas quando foram realizadas comparações pareadas entre G3 e G4 (p=0,0069), com G3 alcançando um melhor selamento contra infiltração bacteriana do que G4.

This in vitro study evaluated, using a bacterial leakage model, whether intracanal medication with calcium hydroxide [Ca(OH)2]-based pastes prepared with different vehicles, has inhibitory effect on corono-apical leakage of bacteria. Forty instrumented human canines were dressed with Ca(OH)2 p.a. associated with: G1= distilled water; G2= polyethylene glycol (PG); G3= PG + CMCP; and G4= glycerin. Five teeth with intact crowns served as negative controls and 5 instrumented teeth without temporary dressing served as positive controls. All teeth were mounted in a 2-chamber apparatus and then exposed to human saliva for 63 days. Leakage was recorded when turbidity was observed in the lower chamber. Fifty percent of the samples of G1 and G2, 10% of G3 and 80% of G4 were fully contaminated after 9 weeks. Statistically significant differences were observed with paired comparisons G3 and G4 (p=0.0069), with G3 achieving better seal against bacterial leakage than G4.

O objetivo do presente trabalho foi avaliar in vitro a atividade antimicrobiana do hipoclorito de sódio (1% e 5%) e da clorexidina (0,12%, 0,5% e 1%). Cepas (ATCC) de Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Porphyromonas gingivalis e Fusobacterium nucleatum foram submetidas ao teste por contato. As amostras foram analisadas em diferentes intervalos de tempo: imediatamente, 5 minutos, 15 minutos e 30 minutos após o contato com cada solução e repetidas 10 vezes. Os resultados demonstraram que a solução de clorexidina a 0,12% não foi capaz de eliminar as amostras de E. faecalis em nenhum intervalo de tempo testado enquanto que a clorexidina a 0,5% e 1% eliminaram todas as cepas testadas assim como as 2 concentrações de hipoclorito de sódio. Estes resultados nos permitem concluir que para se obter melhores respostas quanto a atividade antimicrobiana, a solução de clorexidina deve ser utilizada numa concentração superior a 0,12%.

The purpose of this study was to analyze the in vitro antimicrobial activity of sodium hypochlorite (1% and 5%) and chlorhexidine (0.12%, 0.5% and 1%). Bacterial samples (ATCC) of Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Porphyromonas gingivalis and Fusobacterium nucleatum were submitted to a contact test. Solutions were evaluated at different time intervals: immediately, 5 min, 15 min, and 30 min after contact and repeated 10 times. The results of the contact test showed that 0.12% chlorhexidine did not eliminate E. faecalis at any time interval, while 0.5% and 1% chlorhexidine and 1% and 5% sodium hypochlorite did. These results permit us to conclude that to obtain better antimicrobial activity, chlorhexidine in a concentration greater than 0.12% should be used.