Changes in pH of irrigating solutions after contact with human root dentin / Variaciones del ph de soluciones de irrigación endodónticas en contacto con dentina radicular humana

El objetivo de este trabajo fue estudiar in vitro el comportamiento del pH de diferentes soluciones de irrigación endodónticas, usadas solas o en forma consecutiva, después del contacto con dientes humanos extraídos. Se seleccionaron premolares inferiores. El tercio medio radicular se dividió en 6 partes. Los especímenes obtenidos se dividieron en 6 grupos,de acuerdo a la solución de irrigación empleada: 1) agua destilada; 2) NaClO 1 por ciento; 3) Ácido Cítrico 1 por ciento (AC); 4) EDTA 17 por ciento; 5) AC 1 por ciento + NaClO 1 por ciento ; 6) EDTA 17 por ciento + NaClO 1 por ciento. Los especímenes fueron sumergidos en 1 mL de cada solucióna 37°C. Aquellos del grupo 1, 2 y 3 durante 5 minutos, y el resto, consecutivamente 2,5 minutos. Se determinaron pH inicial y final para cada solución. Los datos fueron analizados utilizando Test T, ANOVA y Test de comparaciones múltiples de Tukey. A los 2,5 y 5 minutos de exposición hubo diferencias estadísticamente significativas entre el pH inicial y final en todas las soluciones. El pH disminuyó en el caso de agua destilada e NaClO, mientras que aumentó en AC y EDTA. In vitro, el pH de todas las soluciones se modificó después del contacto con dentina radicular humana en ambos períodos de tiempo (2,5 y 5 minutos).

The aim of this study was to analyze the in vitro behavior of the pH of different irrigating solutions, used alone or consecutively, after contact with extracted human teeth. Mandibular human premolars were selected. The middle thirds were divided into 6 parts. The specimens obtained were divided into 6 groups and treated with irrigating solutions: 1) distilled water; 2) 1% NaOCl; 3) 1% Citric Acid (CA); 4) 17% EDTA; 5) 1% CA + 1% NaOCl; 6) 17% EDTA + 1% NaOCl. Specimens were immersed in 1 mL of each solution at 37ºC, those of groups 1, 2, 3 and 4, for 5 minutes, and the rest, consecutively for 2.5 minutes in each solution. Initial and final pH of the solutions were determined. Data were analyzed by the T Test, one-way analysis of variance (ANOVA) and Tukey multiple comparison Test. At 2.5 and 5 minutes there were significant differences between the initial and final pH for all solutions. The pH values decreased for distilled water and NaOCl, while they increased for CA and EDTA. In vitro, the pH of all solutions was modified after contact with root dentin at both test times (2.5 and 5 min).

Avaliação histoquímica da permeabilidade dentinária após a utilização do edta como auxiliar na irrigação do canal radicular / Histochemical evaluation of dentin permeability after using edta as auxiliar irrigation of the root canal

O presente estudo avaliou a permeabilidade dentinária em toda a extensão do canal radicular após o uso do EDTA associado a diferentes concentrações de NaOCl. Foram utilizados cinquenta incisivos bovinos divididos em cinco grupos experimentais (n=10) de acordo com as soluções irrigantes empregadas: G1- NaOCl 1%; G2- NaOCl 5,25%; G3- NaOCl 1% + EDTA; G4- NaOCl 5,25% + EDTA; G5- Água destilada (grupo controle). Após o preparo biomecânico, as raízes foram submetidas ao método de coloração histoquímico com sulfato de cobre a 10% e ácido rubeânico a 1% para identificação da permeabilidade dentinária. Para a análise morfométrica as amostras foram seccionadas transversalmente, obtidas três secções de cada terço, desidratadas e clarificadas. Analisadas em microscopia óptica para quantificar a penetração dos íons cobre na dentina radicular. Após a análise estatística dos dados, os resultados indicaram que, houve diferença significativa entre os terços analisados seguindo uma ordem de efetividade do terço cervical maior que o médio e este maior que o apical. Entretanto, nenhuma diferença significante em relação à permeabilidade foi encontrada quando se comparou as diferentes soluções estudadas. Concluiu-se que o uso do EDTA associado com diferentes concentrações de hipoclorito de sódio, como irrigante final, não promoveu alteração na permeabilidade dentinária no canal radicular em relação as soluções usadas isoladamente.

This study evaluated the dentine permeability on the length of the root canal after the use of EDTA associated with different concentrations of NaOCl. Fifty bovine incisors were used divided into five experimental groups (n = 10) according to the irrigating solutions used: G1- 1% NaOCl; G2- 5.25% NaOCl; G3- 1% NaOCl + EDTA; G4- 5.25% NaOCl + EDTA; G5- distilled water (control group). After biomechanical preparation, the roots were subjected to histochemical staining method with 10% copper sulfate and then in 1% rubeanic acid alcohol solution for identification of dentin permeability. For the morphometric analysis the samples were cross sectioned, obtained three sections of each third, dehydrated and clarified. Analyzed with light microscopy to quantify the penetration of copper ions in the root dentin. After statistical analysis, the results indicated that there were significant differences among thirds analyzed by an order of effectiveness of the cervical third larger than the middle and this larger than the apical. However, no significant difference in relation to the permeability was found when comparing the different solutions studied. In conclusion, the use of EDTA associated with different concentrations of sodium hypochlorite, as final rinse, did not cause changes in dentin permeability in relation solutions used alone.

Effect of sodium hypochlorite and edta irrigation, individually and in alternation, on dentin microhardness at the furcation area of mandibular molars

The aim of this study was to evaluate the effect of irrigation regimens on dentin microhardness at the furcation area of mandibular molars, using sodium hypochlorite and ethylenediaminetetraacetic acid (EDTA), individually and in alternation. The occlusal surface and the roots of 20 non-carious extracted human permanent mandibular molars were cut transversally and discarded. The tooth blocks were embedded in acrylic resin and randomly assigned to 4 groups (n=5) according to the irrigating regimens: 1% NaOCl solution, 17% EDTA solution, 1% NaOCl and 17% EDTA and distilled water (control). Knoop microhardness of dentin at the furcation area was evaluated. Data were analyzed using one-way ANOVA and Tukey's multiple comparison tests (α=0.05). The results of this study indicated that all irrigation solutions, except for distilled water (control), decreased dentin microhardness. EDTA did not show a significant difference with NaOCl/EDTA (p>0.05), but showed a significant difference with NaOCl (p<0.01). EDTA and NaOCl/EDTA showed a maximum decrease in microhardness. The 17% EDTA solution, either alone or in combination with 1% NaOCl reduced significantly dentin microhardness at the furcation area of mandibular molars.

A proposta desse estudo foi avaliar o efeito do NaOCl 1% e do ácido etilenodiaminotetracético 17% (EDTA), de forma isolada e alternada, sobre a microdureza dentinária da região da furca de molares inferiores. A superfície oclusal e as raízes de vinte molares inferiores, recém extraídos, foram cortadas transversalmente e descartadas. Os espécimes foram distribuídos em 4 grupos (n=5) de acordo com a solução irrigante utilizada. As soluções empregadas foram EDTA 17% (I), NaOCl 1% (II), NaOCl 1% e EDTA 17% (III), e água destilada (IV) (controle). Os dentes foram incluídos em blocos de resina acrílica e cortados transversalmente. A hemi-secção que melhor representou a furca dental foi lixada e polida para a avaliação da microdureza Knoop. As medidas obtidas foram analisadas utilizando-se teste ANOVA seguido do teste de comparação múltipla de Tukey (α=0,05). Os resultados desse estudo mostraram que todas as soluções, exceto o grupo controle, diminuíram a microdureza dentinária. O EDTA não apresentou diferença estatística significante em relação ao NaOCl/EDTA (p>0,05), mas foi diferente do NaOCl (p<0,01). Os grupos do EDTA e NaOCl/EDTA mostraram a maior redução da microdureza. A solução de EDTA 17%, associada ou não ao NaOCl 1% reduz, significantemente, a microdureza dentinária da furca de molares inferiores.

Effect of endodontic irrigating solutions on the microhardness and roughness of root canal dentin: An in vitro study.

Context: To evaluate the effect of widely used endodontic irrigating solutions on root dentin microhardness and surface roughness. Materials and Methods: One hundred twenty, non-carious extracted human permanent incisor teeth were selected. The crowns of the teeth were sectioned and the roots were separated longitudinally to get 240 specimens. These specimens were then divided into six groups according to the irrigating solutions used. The solutions used were 5% and 2.5% NaOCl solutions, 3% H2 O2 , 17% EDTA solution, 0.2% chlorhexidine gluconate, and distilled water. Then, the specimens were subjected to microhardness and roughness testing. The data were analyzed using ANOVA and Tukey's multiple comparison tests. Results: The results of this study indicated that all irrigation solutions, except 0.2% chlorhexidine gluconate, decreased the microhardness of root dentin, and 3% H2 O2 and 0.2% chlorhexidine gluconate had no effect on surface roughness. Conclusions: Within the limitation of this study, it is concluded that 0.2% chlorhexidine gluconate seems to be an appropriate irrigation solution, because of its harmless effect on the microhardness and surface roughness of root canal dentin.

Accuracy Of A New Apex Locator Apex NRG Blue-- An Invitro Study.

The purpose of this study was to test in an in-vitro model the accuracy of a new multi frequency third generation apex locator Apex NRG blue both in dry and various wet environments. 60 extracted teeth were taken. The teeth were divided into 6 groups of 10 each. The actual length of the root canal of each tooth was determined and then the teeth were embedded in an alginate model. The radiographic working length was determined and later the electronic working length was taken using different irrigating solutions, (3%H2O2, 3%Naocl, 0.2% chlorhexidine, normal saline and 17%EDTA). The results were compared and sent for statistical analysis. This study showed that the new multi frequency electronic apex locator NRG blue is quiet reliable in determining the root canal length both in dry as well as in wet environment.

Cleaning of flattened root canals with different irrigating solutions and nickel-titanium rotary instrumentation

The aim of this study was to evaluate the cleaning capacity of Profile .04 files combined with different irrigating solutions in flattened root canals using histological, morphometrical and SEM analyses. Eighty human mandibular incisors were prepared with Profile .04 instruments and randomly divided into 4 groups according to the irrigating solutions used (n=20): G1: distilled water (control); G2: 1 percent sodium hypochlorite (NaOCl); G3: 1 percent NaOCl alternated with 17 percent EDTA, and G4: 1 percent NaOCl with RCPrep cream. Ten teeth of each group were evaluated with an optical microscope to determine the percentage of root canal debris. The remaining teeth were evaluated under scanning electron microscopy (SEM). Data were analyzed statistically by ANOVA and Tukey's test (á=0.01).There was a significant difference (p<0.001) among the groups regarding the percentage of debris left in the canals (distilled water: 18.82 ± 5.55; 1 percent NaOCl: 6.29 ± 5.55; 1 percent NaOCl + 17 percent EDTA: 12.47 ± 6.92; 1 percent NaOCl + RCPrep: 7.82 ± 1.91). The SEM analysis showed the best results for 1 percent NaOCl + 17 percent EDTA on smear layer removal. It may be concluded that the combination of Profile .04 rotary instrumentation and the tested solutions was not able to totally remove debris and smear layer from flattened root canals.

O objetivo deste estudo foi avaliar a capacidade de limpeza dos instrumentos Profile .04 associados a diferentes soluções irrigantes, em canais radiculares achatados, por meio de análises histológica, morfométrica e MEV. Oitenta incisivos inferiores humanos foram submetidos ao preparo biomecânico com instrumentos Profile .04 e aleatoriamente distribuídos em 4 grupos de acordo com as soluções irrigantes usadas (n=20): G1 - água destilada (controle); G2 - NaOCl 1 por cento; G3 - NaOCl 1 por cento alternado com EDTA 17 por cento e G4 - NaOCl 1 por cento com RCPrep creme. Dez dentes de cada grupo foram avaliados em microscopia óptica para determinação da porcentagem de debris do canal radicular. Os demais dentes foram avaliados em microscopia eletrônica de varredura. A análise estatística mostrou diferença significante (p<0,001) entre os grupos ao considerar a porcentagem de debris remanescente nos canais (água destilada: 18,82 ± 5,55; NaOCl: 6,29 ± 5,55; NaOCl + EDTA: 12,47 ± 6,92; NaOCl + RCPrep: 7,82 ± 1,91). A análise em MEV evidenciou melhores resultados na remoção da camada de smear com o NaOCl 1 por cento alternado com EDTA 17 por cento. Pode-se concluir que a associação entre a instrumentação rotatória com Profile .04 e as soluções testadas não foi capaz de remover totalmente debris e camada de smear de canais radiculares achatados.

Efficacy of sodium hypochlorite and chlorhexidine against Enterococcus faecalis: a systematic review

The efficacy of the sodium hypochlorite (NaOCl) and chlorhexidine (CHX) on Enterococcus faecalis was evaluated by systematic review and meta-analysis. The search strategies included search in electronic biomedical journal databases (MEDLINE, EMBASE, CENTRAL) and handsearching records, using different matches of keywords for NaOCl, CHX and Enterococcus faecalis. From 41 in vivo studies, 5 studies met the inclusion criteria. In a sample containing 159 teeth, E. faecalis was detected initially in 16 (10%) teeth by polymerase chain reaction (PCR) and 42 (26.4%) teeth by microbial culture techniques. After root canal disinfection, this species was observed in 11 (6.9%) teeth by PCR and 12 (7.5%) teeth by culture. Risk differences of included studies were combined as generic inverse variance data type (Review Manager Version 5.0 _ Cochrane Collaboration, http://www.cc-ims.net, accessed 15 May 2008), taking into account the separate tracking of positive and negative cultures/PCR. The level of statistical significance was set at p<0.05. In conclusion, NaOCl or CHX showed low ability to eliminate E. faecalis when evaluated by either PCR or culture techniques.

Estudo in vitro da infiltração marginal em restaurações provisórias após tratamento endodôntico / In vitro study of lateral leakage in temporary restorations after endodontic treatment

O presente estudo avaliou in vitro a infiltração marginal de dois materiais restauradores utilizados como seladores provisórios após tratamento endodôntico. Foram selecionados 40 molares íntegros, nos quais, após o tratamento endodôntico, padronizou-se cavidades com 4mm de profundidade e 2mm de espessura de parede dentária bpara inserção do material selador; originando dois grupos com 20 corpos-de-prova cada: Grupo I - Coltosol e Grupo II - Vitremer. Procedeu-se então a termociclagem e a impermeabilização dos espécimes, onde foi aplicado o cianocrilato em toda a superfície do dente, com exceção de 1 mm da interface dente/material. Logo após, metade de cada grupo foi imerso no corante azul de metileno a 2 por cento, com ph 7,2, por 7 dias, enquanto que a outra metade permaneceu imerso na solução corante por 30 dias...

This in vitro study evaluated the marginal leakage of two temporary coronal filling materials after root canal treatment. Standardized cavities accesses were prepared in 40 intact human permanent molar teeth. They were divided into two groups consisting of 20 samples. The teeth were restored using one of the temporary filling materials, namely: Coltosol and Vitremer. After thermocycling, the experimental teeth applied on the coronal enamel, leaving a clear area of 1mm around the filling material. Then the samples were immersed in 2 percent methylene blue dye solution for leakage assessment

Estudo in vitro da atividade antimicrobiana de soluções irrigadoras na eliminação de Enterococcus faecalis / In vitro study of antimicrobial activity of irrigating solutions in the elimination of Enterococcus faecalis

Bactérias facultativas como Enterococcus faecalis têm sido isoladas de patologias ligadas a canais radiculares, sendo consideradas uma das espécies mais resistentes da cavidade oral e uma das possíveis causas de falha nos tratamentos endodônticos. O objetivo deste estudo foi avaliar, in vitro, a efetividade de várias soluções irrigadoras na eliminação de Enterococcus faecalis. Foi aplicado o teste de disco-difusão em ágar neste trabalho. A bactéria utilizada foi Enterococcus faecalis (ATCC29212), e as soluções irrigadoras foram NaOCl 0,5%, 1%, 2,5% e 5%; clorexidina 0,12% e 2%; EDTA 17%; e H2O2 10 vol. A clorexidina 2% e NaOCl 5% foram as soluções irrigadoras mais eficientes, e NaOCl 0,5%, EDTA 17% e H2O2 mostraram-se inefetivas na eliminação dessa espécie. Os resultados sugerem que a eliminação de E. faecalis depende da concentração e do tipo de solução irrigadora utilizada

Facultative bacteria such as Enterococcus faecalis, have been isolatedfrom pathologically involved root canals, being considered one of themost resistant species in the oral cavity one of the possible causes offailure of root canal treatment. The aim of this study was to assess, invitro, the effectiveness of the several irrigating solutions in theelimination of Enterococcus faecalis. The disk-diffusion in agar testwas utilized in this study. The bacteria utilized was Enterococcus faecalisATCC 29212 and the irrigating solutions were NaOCl 0,5%, 1%, 2,5%and 5%; chlorhexidine 0,12% and 2%; EDTA 17% and H2O2 10 vol. Chlorhexidine 2% and NaOCl 5% were the most effective irrigators andNaOCl 0,5%; EDTA 17% and H2O2 showed ineffectiveness in theelimination of this specie. These results suggest that the elimination ofE. faecalis depends on the concentration and type of irrigator used