Effectiveness of nanoparticles solutions and conventional endodontic irrigants against Enterococcus faecalis biofilm

To overcome the challenge imposed by the presence of biofilm and reach significant bacterial reduction of the root canals, many irrigants have been indicated during endodontic treatment, among them nanoparticles solutions. Aims: This study aims to evaluate the effectiveness of experimental solutions containing silver and zinc oxide nanoparticles (ZnO Np) and conventional endodontic irrigants against Enterococcus faecalis biofilm, in root canals. Methods: Seventy-six extracted human teeth were biomechanically prepared and sterilized. The root canal surface was exposed to E. faecalis suspension to form a 7-day-old biofilm. Four teeth were analyzed by scanning electron microscopy (SEM) to confirm the presence of biofilm. The remaining teeth were randomly divided into 6 groups (n = 12) and treated with passive ultrasonic irrigation and different solutions: G1 – 0.85% saline (control); G2 – 2% chlorhexidine gluconate (CHX); G3 – 5% sodium hypochlorite (NaOCl); G4 – 1% NaOCl; G5 – 1% silver nanoparticles (Ag Np) solution; and G6 – 26% ZnO Np solution. The susceptibility of E. faecalis biofilms to disinfecting solutions (n = 10) was determined by quantification of colony-forming units. SEM analysis was also carried out to examine the biofilm structure after treatments (n = 2). Data were analyzed by Kruskal–Wallis and Dunn post hoc tests (P < 0.05). Results: All tested solutions showed superior effectiveness compared to 0.85% saline (P < 0.05). Overall, 2% CHX presented the most effective action against E. faecalis biofilm, followed by 5% NaOCl, 1% Ag Np, 26% ZnO Np, and 1% NaOCl. Conclusions: 1% Ag Np and 26% ZnO Np were effective against E. faecalis biofilm similarly to conventional endodontic irrigants.

A atuação do odontolegista do Instituto Médico Legal de Florianópolis (SC) no processo de identificação Post Mortem / The forensic dentistry action in the Legal Medical Institute Of Florianópolis (SC) in the process of Post Mortem indentification

O objetivo deste estudo foi avaliar a atuação do odontolegista no processo de identificação post mortem do Instituto Médico Legal da cidade de Florianópolis, SC. Para tanto, foi realizada uma análise retrospectiva dos casos de identificação post mortem registrados no Instituto Médico Legal no período de 2005 a 2014. Destes, foram selecionados apenas os laudos periciais de identificação post mortem odontológicos. Foram avaliados 6.511 laudos: os quais 26 foram laudos de identificação post mortem realizados pelo odontolegista. Dentre os 26 laudos, 13 casos foram identificados, sendo que 7 (53,84%) por meio do prontuário odontológico da vítima, 4 (30,76%) por prontuário e exame radiográfico, 1 (7,1%) por prontuário/registro de mordida e placa de acrílico e 1 (7,1%) por foto extrabucal. Os outros 13 casos resultaram em não identificação, pois 12 (46,2%) casos não apresentaram prontuário e em 1 (3,8%) caso houve o incompleto preenchimento do prontuário odontológico, resultando na impossibilidade de identificação dos cadáveres. Conclui-se que a atuação do odontolegista no processo de identificação post mortem no IML Florianópolis forneceu informações eficazes para a identificação de 13 casos em 9 anos e que o método de comparação de prontuário odontológico ante e post mortem foi o mais utilizado nas identificações

The purpose of this study is to evaluate the acting of the forensic dentist in the process of the post mortem iden-tification in the National Legal Medicine Institute of Florianópolis, SC. For this matter, a retrospective analysis of post mortem cases identification registered in the National Legal Medicine Institute of Florianópolis, in the period of 2005 to 2014, was done. From these, were selected only the expert reports of odontological post mortem identification. 6.511 expert report were evaluated, though 26 was post mortem identification reports made by the forensic dentist. Among the 26 reports, 13 cases were identified of which 7 (53,84%) through dental records of the victim, 4 (30,76%) mecial record and radiographic examination, 1 (7,1%) record/bite registration material and acrylic plate, and 1 (7,1%) by extraoral photo. The other 13 cases were resulted in no identification, for 12 (46,2%) cases did not present records and in 1 (3,8%) case there was the incomplete filling of the odontological record, resulting in the impossibility of the identification of the corpses. In conclu¬sion, the acting of the forensic dentist in the process of the post mortem identification in the National Legal Medicine Institute of Florianópolis provided effective informations to an identification of 13 cases in 9 years that the method of comparison of the ondontological record ante mortem and post mortem was the most used in the identifications

Potencial capacidade de selamento de um novo cimento à base de própolis, utilizado como tampão apical, comparado ao MTA / Potential sealing ability of a new propolis based cement, used as a buffer apical, compared to MTA

Objetivo: o principal objetivo desse estudo foi avaliar e comparar a capacidade de selamento de um cimento ex-perimental à base de própolis (EPC) e do agregado de trióxido mineral (MTA), empregados na forma de tampão apical, utilizando o sistema de infltração de glicose. Em se-guida, um teste de infltração bacteriana foi utilizado para avaliar a capacidade de selamento do EPC. Métodos: para o teste de infltração de glicose, trinta segmentos radiculares (12mm) foram divididos aleatoriamente em dois grupos experimentais (n = 15) de acordo com o cimento utilizado na confecção do tampão apical, conforme se-gue: G1 = MTA; G2 = EPC. Os segmentos radiculares foram preparados e a quantidade de glicose infltrada foi mensurada, seguindo uma reação enzimática, e quantif-cada por meio de um espectrofotômetro. Os dados foram analisados pelo teste t de Student (p < 0,05). Para o teste de infltração bacteriana, outros 15 dentes foram submeti-dos aos procedimentos de apexifcação, preenchidos com EPC e montados em um aparato específco. O número de espécimes infiltrados foi observado, semanalmente, durante 70 dias. Resultados: o EPC foi signifcativamente superior ao MTA (p < 0,001). A capacidade de selamento do EPC foi 100% e 60% efciente nos testes de infltração de glicose e bactérias, respectivamente. Conclusão: o cimento experimental à base de própolis, na forma de tam-pão apical, promoveu superior capacidade de selamento, comparado ao MTA, e excelente desempenho em ambos os testes de infiltração.

Influence of phosphate buffered saline on the bond strength of endodontic cement to dentin

Aim: To analyze the influence of exposure and time of exposure to phosphate buffered saline (PBS) on the push-out bond strength (BS) of Biodentine to dentine. Methods: Eighty 2-mm-thick dentin discs were obtained from transversal sections of human teeth roots. The space of the canal was enlarged using #2-#5 Gates-Glidden burs to obtain 1.3-mm-diameter standardized cavities. The discs were immersed in 17% EDTA followed by 1% NaOCl and dried. The spaces of the canals were filled with Biodentine and the samples were divided into 2 groups (n=40) according to the storage: G1: exposure to moistened cotton pellet; G2: exposure to PBS. After 30 min, 1, 3 and 28 days, 10 samples of each group were subjected to the push-out test. Data were analyzed using ANOVA and Tukey test (p < 0.05). Results: The specimens exposed to PBS had lower BS (p < 0.05), except for the 1-day period (p = 0.6017). In specimens of Group 1 the BS increased up to 3 days (p < 0.05). In specimens in Group 2, the BS increased from 30 min to 1 day (p < 0.0001) and remained stable up to 3 days (p = 0.9876). At 28 days, a significant decrease was observed in the BS values of both groups (p < 0.05). Conclusions: The exposure of Biodentine to PBS led to lower BS values. In general, the BS increased gradually up to 3 days and reduced at 28 days.

Avaliação ex vivo da infiltração coronária em canais obturados com MTA FILLAPEX e AH Plus / Ex vivo evaluation of coronal leakage in root canals filled with MTA FILLAPEX and AH Plus

O objetivo deste estudo foi avaliar a infiltração coronária em canais obturados com AH Plus e MTA FILLAPEX. Trinta pré-molares unirradiculados foram divididos aleatoriamente em 2 grupos (n = 15) de acordo com o cimento obturador utilizado: G1: MTA FILLAPEX e G2: AH Plus. O teste de infiltração do corante nanquim foi conduzido sob pressão de 60 KPa, por 8 min. Após diafanização, foi avaliada a penetração do corante nos terços radiculares. Houve infiltração em 8 e 7 amostras dos G1 e G2, respectivamente. Em nenhuma amostra do G2, o corante atingiu o terço apical. Em quatro amostras do G1, o corante foi visualizado no terço apical. O AH Plus demonstrou uma qualidade de selamento superior ao MTA FILLAPEX.

The aim of this study was evaluate the coronal leakage in root canals filled with AH Plus and MTA FILLAPEX. Thirty single-rooted premolars were randomly divided into two experimental groups (n = 15) according to the sealer used: G1: MTA FILLAPEX and G2: AH Plus. The dye leakage test ink was conducted under pressure of 60 kPa for 8 min. After diaphanization, the dye penetration was evaluated by root thirds. Results: Eight samples form G1 and seven samples from G2 showed infiltration. In any sample from G2, the dye reached the apical third. In four samples from G1, the dye was visualized in the apical third. The AH Plus showed a superior sealing quality of the MTA FILLAPEX.