Effects of EDTA gel and chlorhexidine gel on root dentin permeability.

The aim of this study was to evaluate the effect of 24% ethylenediaminetetraacetic acid (EDTA) gel and 2% chlorhexidine gel (CHX) in dentin permeability and smear layer removal from root canals instrumented with NiTi rotary system using histochemical staining and scanning electron microscopy (SEM) analysis. Overall, 43 premolars were classified into two experimental groups, EDTA (n = 20) and CHX (n = 20), and a negative control (NC) (n = 3). All specimens were instrumented and the irrigant solutions were used after each file change. The EDTA group received a final rinse with 5-ml 1% NaOCl followed by a 5-ml 0.9% saline solution; the CHX group received a final rinse with 10-ml 0.9% saline solution; and the negative control group received a final rinse with only 0.9% saline solution. Fifteen teeth from each group were prepared for histochemical staining and evaluation of dentin permeability using the image-scanning software Axion Vision (v.4.8.2). Five remaining teeth were prepared for analysis using SEM for morphological analysis. The study found that 24% EDTA gel increased the permeability of dentin in all thirds evaluated and also demonstrated an increased cleaning ability, with dentinal walls free of smear layer and open dentinal tubules, as compared to 2% CHX gel. It was concluded that EDTA was efficient in cleaning the dentinal tubules and increased dentin permeability.

Effectiveness of home bleaching agents in discolored teeth and influence on enamel microhardness.

OBJECTIVES: This study evaluated the effectiveness of different home bleaching agents on color alteration and their influence on surface and subsurface microhardness of discolored bovine enamel. MATERIAL AND METHODS: Forty-five fragments of bovine incisors were randomly allocated into 3 groups (n=15) according to the bleaching agent: 10% carbamide peroxide gel (CP10), 16% carbamide peroxide gel (CP16) and 6.5%-hydrogen-peroxide-based strip (HP6.5). Before bleaching treatment, initial values of Knoop surface microhardness and color (CIEL a b) were obtained and the fragments were artificially stained in hemolyzed rat blood. Then, bleaching treatments were performed over a 21-day period. Color changes (DeltaE) were assessed at 7, 14 and 21 days, and final surface microhardness reading was done after 21 days. Thereafter, the fragments were bisected to obtain subsurface microhardness. Data were subjected to ANOVA and Tukey's tests (alpha=5%). RESULTS: Color changes produced by CP16 were similar to those of CP10, and the color changes produced by these materials were significantly superior to those produced by HP6.5. Color changes at 21 days were superior to 7 days and similar to 14 days. The time did not influence color changes for CP16, which showed similarity between the 14- and 21-day results. No statistically significant differences were found among the home bleaching agents for surface and subsurface microhardness. CONCLUSIONS: Microhardness of bovine enamel was not affected by the bleaching agents. The 16% carbamide peroxide gel was the most effective for bleaching the stained substrate.

Effectiveness of home bleaching agents in discolored teeth and influence on enamel microhardness

OBJECTIVES: This study evaluated the effectiveness of different home bleaching agents on color alteration and their influence on surface and subsurface microhardness of discolored bovine enamel. MATERIAL AND METHODS: Forty-five fragments of bovine incisors were randomly allocated into 3 groups (n=15) according to the bleaching agent: 10 percent carbamide peroxide gel (CP10), 16 percent carbamide peroxide gel (CP16) and 6.5 percent-hydrogen-peroxide-based strip (HP6.5). Before bleaching treatment, initial values of Knoop surface microhardness and color (CIEL*a*b*) were obtained and the fragments were artificially stained in hemolyzed rat blood. Then, bleaching treatments were performed over a 21-day period. Color changes (ÄE) were assessed at 7, 14 and 21 days, and final surface microhardness reading was done after 21 days. Thereafter, the fragments were bisected to obtain subsurface microhardness. Data were subjected to ANOVA and Tukey's tests (á=5 percent). RESULTS: Color changes produced by CP16 were similar to those of CP10, and the color changes produced by these materials were significantly superior to those produced by HP6.5. Color changes at 21 days were superior to 7 days and similar to 14 days. The time did not influence color changes for CP16, which showed similarity between the 14- and 21-day results. No statistically significant differences were found among the home bleaching agents for surface and subsurface microhardness. CONCLUSIONS: Microhardness of bovine enamel was not affected by the bleaching agents. The 16 percent carbamide peroxide gel was the most effective for bleaching the stained substrate.

Effect of different bleaching systems on the ultrastructure of bovine dentin.

The aim of this study was to evaluate in vitro the effect of different in-office bleaching systems on the surface morphology of bovine dentin. Thirty tooth fragments measuring 4 x 4mm, containing enamel and dentin, were obtained from the crowns of extracted bovine incisors. Samples were subjected to simulated intracoronal bleaching techniques using conventional (Opalescence Endo and Whiteness Super Endo) and light-activated systems (Opalescence Xtra) and Whiteness HP Maxx). Controls were treated with either sodium perborate mixed with 10% hydrogen peroxide or no bleaching agent. The samples were observed under SEM and the recorded images were evaluated for topographic alterations. The ultrastructural alterations of dentin observed in this study varied greatly between groups according to the products used. Higher pH products (Whiteness HP Maxx) and Opalescence Xtra) associated with in-office techniques yielded better maintenance of dentin ultrastructure. Apparently, both low pH and hydrogen peroxide oxidation play a role in altering the ultrastructure of dentin during internal dental bleaching. The use of alkaline products with reduced time of application (in-office techniques) may decrease such morphological alterations.

In vitro study of the pulp chamber temperature rise during light-activated bleaching.

This study evaluated in vitro the pulp chamber temperature rise induced by the light-activated dental bleaching technique using different light sources. The root portions of 78 extracted sound human mandibular incisors were sectioned approximately 2 mm below the cementoenamel junction. The root cavities of the crowns were enlarged to facilitate the correct placing of the sensor into the pulp chamber. Half of specimens (n=39) was assigned to receive a 35% hydrogen peroxide gel on the buccal surface and the other halt (n=39) not to receive the bleaching agent. Three groups (n=13) were formed for each condition (bleach or no bleach) according to the use of 3 light sources recommended for dental bleaching: a light-emitting diode (LED)laser system, a LED unit and a conventional halogen light. The light sources were positioned perpendicular to the buccal surface at a distance of 5 mm and activated during 30 s. The differences between the initial and the highest temperature readings for each specimen were obtained, and, from the temperature changes, the means for each specimen and each group were calculated. The values of temperature rise were compared using Kruskal-Wallis test at 1% significance level. Temperature rise varied significantly depending on the light-curing unit, with statistically significant differences (p<0.01) among the groups. When the bleaching agent was not applied, the halogen light induced the highest temperature rise (2.38+/-0.66 degrees C). The LED unit produced the lowest temperature increase (0.29+/-0.13 degrees C); but there was no significant difference between LED unit and LED-laser system (0.35+/-0.15 degrees C) (p>0.01). When the bleaching agent was applied, there were significant differences among groups (p<0.01): halogen light induced the highest temperature rise (1.41+/-0.64 degrees C), and LED-laser system the lowest (0.33+/-0.12 degrees C); however, there was no difference between LED-laser system and LED unit (0.44+/-0.11 degrees C). LED and LED-laser system did not differ significantly from each other regardless the temperature rise occurred with or without bleaching agent application. It may be concluded that during light-activated tooth bleaching, with or without the bleaching agent, halogen light promoted higher pulp chamber temperature rise than LED unit and LED-laser system. The tested light-curing units provided increases in the pulp chamber temperature that were compatible with pulpal health.

In vitro study of the pulp chamber temperature rise during light-activated bleaching

This study evaluated in vitro the pulp chamber temperature rise induced by the light-activated dental bleaching technique using different light sources. The root portions of 78 extracted sound human mandibular incisors were sectioned approximately 2 mm below the cementoenamel junction. The root cavities of the crowns were enlarged to facilitate the correct placing of the sensor into the pulp chamber. Half of specimens (n=39) was assigned to receive a 35 percent hydrogen peroxide gel on the buccal surface and the other halt (n=39) not to receive the bleaching agent. Three groups (n=13) were formed for each condition (bleach or no bleach) according to the use of 3 light sources recommended for dental bleaching: a light-emitting diode (LED)laser system, a LED unit and a conventional halogen light. The light sources were positioned perpendicular to the buccal surface at a distance of 5 mm and activated during 30 s. The differences between the initial and the highest temperature readings for each specimen were obtained, and, from the temperature changes, the means for each specimen and each group were calculated. The values of temperature rise were compared using Kruskal-Wallis test at 1 percent significance level. Temperature rise varied significantly depending on the light-curing unit, with statistically significant differences (p<0.01) among the groups. When the bleaching agent was not applied, the halogen light induced the highest temperature rise (2.38±0.66ºC). The LED unit produced the lowest temperature increase (0.29±0.13ºC); but there was no significant difference between LED unit and LED-laser system (0.35±0.15ºC) (p>0.01). When the bleaching agent was applied, there were significant differences among groups (p<0.01): halogen light induced the highest temperature rise (1.41±0.64ºC), and LED-laser system the lowest (0.33±0.12ºC); however, there was no difference between LED-laser system and LED unit (0.44±0.11ºC). LED and LED-laser ...

Evaluation of dentin permeability after light activated internal dental bleaching.

The aim of this in vitro study was to assess quantitatively the dentin permeability of human teeth after intracoronal bleaching therapy with 35% hydrogen peroxide activated by LEDs, halogen lamp or using the walking bleach technique. Forty human maxillary central incisors had standard access cavities performed and the cervical thirds of the canals were prepared with Gates-Glidden drills up to a size 130. Roots were resected between the coronal and middle thirds and the apical portions were discarded. A glass ionomer, 2 mm thick cervical plug was placed inside the canal, at the cement-enamel junction level. Group I received 35% hydrogen peroxide gel activated by LEDs. Group II was submitted to 35% hydrogen peroxide gel activated by halogen lamp. Group III received 35% hydrogen peroxide gel and the walking bleach technique was followed. Group IV (control) received a dry cotton pellet inside the pulp chamber with temporary restoration. Dentinal permeability was quantified by copper ion penetration. Linear measurements were obtained by analysis of digital images under x 5 magnification. Mean values and SD for the experimental groups were: I, 7.1% (+/-3.2%); II, 8.4% (+/-3.0%); III, 9.1% (+/-3.0%); IV, 1.3% (+/-2.8%). One-way ANOVA was used to analyze the results. Results showed an increase of permeability values for groups I, II and III when compared to group IV (control); however, no statistical differences were found between the three tested bleaching techniques. It can be concluded that 35% hydrogen peroxide activated by LED, halogen lamp or used following the walking bleach technique produced similar increase in dentinal permeability.

A scanning electron microscopic evaluation of different root canal irrigation regimens.

The purpose of this study was to assess the effectiveness of endodontic irrigants in removing the smear layer from instrumented root canal walls using Scanning Electron Microscopy (SEM). The endodontic irrigants used were: 1% sodium hypochlorite (NaOCl); 1% NaOCl mixed to 17% EDTAC; 2% chlorhexidine gel; and Ricinus communis gel. Photomicrographs of the middle and apical thirds were evaluated with the aid of the Fotoscore - v. 2.0 software. The results indicated that the mixture of sodium hypochlorite and EDTAC completely removed the smear layer from dentinal walls. The other endodontic irrigants were not as efficient in cleansing the root canals.

Effect of bleaching agents on enamel permeability.

PURPOSE: To evaluate enamel permeability after external bleaching procedures. METHODS: The coronal portion of 75 human canines were covered with an acid resistant varnish, except for a 7.1 mm2 circular area on the labial surface and, according to a randomized complete block design, specimens were allocated to bleaching treatments using carbamide peroxide-containing agents (CP): 10%, 16% or 37%; or a 35% hydrogen peroxide product (HP). The control group was exposed to artificial saliva. The bleaching agents were applied following the manufacturer's recommendations over 21 days. In between bleaching exposures, specimens were stored in artificial saliva. Samples were then prepared according to a histochemical coloring method based on copper sulfate and dithiooxamide solutions. Digital images captured in an optical microscope were used to measure the percentage of copper ion penetration over the total enamel thickness on three sections taken from the exposed area. RESULTS: Analysis of Deviance showed a significant difference for the permeability values among groups (P = 0.046). Likelihood ratio test revealed that the use of the CP10% and HP35% agents caused significantly greater enamel permeability than did the control treatment. No significant differences in percentage of copper ion penetration were found among CP10%, CP16%, CP37% and HP35%. This in vitro study demonstrated that depending on the external bleaching procedure, enamel permeability may be increased.

A scanning electron microscopic evaluation of different root canal irrigation regimens / Avaliação por microscopia eletrônica de varredura de diferentes regimes irrigantes no canal radicular

The purpose of this study was to assess the effectiveness of endodontic irrigants in removing the smear layer from instrumented root canal walls using Scanning Electron Microscopy (SEM). The endodontic irrigants used were: 1 percent sodium hypochlorite (NaOCl); 1 percent NaOCl mixed to 17 percent EDTAC; 2 percent chlorhexidine gel; and Ricinus communis gel. Photomicrographs of the middle and apical thirds were evaluated with the aid of the Fotoscore - v. 2.0 software. The results indicated that the mixture of sodium hypochlorite and EDTAC completely removed the smear layer from dentinal walls. The other endodontic irrigants were not as efficient in cleansing the root canals.

A proposta deste estudo foi avaliar, por meio de microscopia eletrônica de varredura (MEV), a efetividade dos irrigantes endodônticos na remoção da "smear layer" das paredes dos canais radiculares instrumentados. Os irrigantes endodônticos utilizados foram: solução de hipoclorito de sódio a 1 por cento; solução de hipoclorito de sódio a 1 por cento misturado ao EDTAC a 17 por cento, gel de clorexidina a 2 por cento e gel de Ricinus communis. Fotomicrografias dos terços médio e apical foram avaliadas com o auxílio do software Fotoscore - versão 2.0. Os resultados indicaram que a mistura da solução de hipoclorito de sódio e EDTAC removeu eficientemente a "smear layer" das paredes dentinárias. Os demais irrigantes endodônticos não foram tão eficientes na limpeza dos canais.

Avaliação in vitro das alterações promovidas em canais radiculares artificiais curvos após instrumentação com as técnicas ápico-cervical e cérvico-apical / An in vitro evaluation of changes in curved artifical root canals after instrumentation with step-back and crown-down techiniques

O presente trabalho teve por objetivo verificar, in vitro, as alterações promovidas pelos preparos dos canais radiculares artificiais curvos com instrumentos de aço inoxidável (Dyna instruments), cotejando as técnicas: ápico-cervical e cérvico-apical. Foram avaliados os desgastes ocorridos em três níveis: 2, 4 e 11 milímitros do final apical do canal simulado, assim como as áreas apical e cervical da parte curva. Nos níveis analisados, foi verificado que ocorreu diferença estatisticamente significante em 5%, no nível de 2 milímetros, e 15 para o nível de 4 milímetros. Para o nível de 11 milímetros, não houve diferença significativa. Para a área apical da curvatura foi observada significância em 1%, e para a área cervical, resultado estatisticamente significante em 5%. Foi concluido que baseados na metodologia empregada, os preparos no sentido cérvico-apical tendem a diminuir a ocorrência de acidentes em canais radiculares artificiais curvos, produzido preparos mais centrados em relação aos canais simulados instrumentados pela técnica ápico-cervical.

In vitro assessment of dentinal permeability after the use of ultrasonic-activated irrigants in the pulp chamber before internal dental bleaching.

This in vitro study aimed to assess dentin permeability quantitatively after the use of different irrigants into the pulp chamber, with or without ultrasonic activation, before the application of an internal bleaching agent. Thirty maxillary anterior teeth, treated endodontically, were randomly assigned to six groups, according to the irrigant used: group I, distilled water; group II, 17% EDTA; group III, 1% sodium hypochlorite; for groups IV, V, and VI, respectively, the same solutions were used, but were ultrasonicated. In groups I, II, and III, the irrigant that filled the pulp chamber was left undisturbed for 15 s and was then aspirated; in groups IV, V, and IV, the irrigants were placed into the pulp chamber, ultrasonic-activated for 15 s, and were then aspirated. This sequence was repeated three times for all groups. Afterwards, for all groups, the pulp chamber was dried, filled with a bleaching agent, and sealed with glass ionomer cement. At each change of the whitening agent, these procedures were repeated. Then, the temporary restorations were removed, access cavities were cleaned, and teeth were immersed in a 10% copper sulfate aqueous solution, submitted to vacuum and immersed in a 1% rubianic acid alcohol solution. Copper ion penetration was revealed by the rubianic acid. After staining, roots were removed at the cemento-enamel junction (CEJ) and sectioned in a mesiodistal direction starting from the cervical plug level. The sections were thinned, observed under an optical microscope, the images were digitized, and copper ion penetration was measured in each section using a specific software. Means and SD were: group I, 2.41 (+/-1.45); group II, 5.22 (+/-1.79); group III, 8.32 (+/-2.55); group IV, 3.73 (+/-0.89); group V, 14.83 (+/-4.99); and group VI, 10.51 (+/-2.65). Statistical analysis using two-way anova and Tukey test showed that, regardless of the irrigant, ultrasonication increased dentinal permeability (P < 0.01). Comparing the overall effectiveness of the tested solutions, EDTA yielded the greatest increase in dentinal permeability (P < 0.01). Based on these results, it may be concluded that use of ultrasonic-activated irrigants in the pulp chamber, before the accomplishment of internal dental bleaching procedures, may result in a remarkable increase of dentin permeability, which may enhance the efficiency of the whitening agent.

Effect of internal bleaching agents on dentinal permeability of non-vital teeth: quantitative assessment.

The aim of this in vitro study was to assess quantitatively dentin permeability of pulpless teeth after intracoronal bleaching therapy with three different agents. Twenty-four maxillary central incisors were randomly assigned to four groups according to the bleaching agent used: I--non-bleached control; II--37% carbamide peroxide; III--sodium perborate/20% hydrogen peroxide paste; IV--27% carbamide peroxide. After standard access and root-canal preparation the access opening, biomechanical preparation and root-canal filling, a cervical glass ionomer plug was prepared and intracoronal bleaching procedures were carried out in a standardized fashion. The access cavities were opened and the teeth were externally sealed and immersed in a 10% copper sulfate aqueous solution for 30 min, in vacuum for the first 5 min. Then, samples were removed, dried with absorbing paper and immersed in a 1% rubianic acid alcohol solution, for the same above-mentioned period in solution and in vacuum. Copper ion penetration was indicated by the rubianic acid staining. Mean values and SD for the experimental groups were: I--7.88% (+/-1.33), II--16.94% (+/-5.72); III--11.45% (+/-3.90) and IV--8.98% (+/-4.19). Data were submitted to one-way anova. The results showed that the 37% carbamide peroxide provided the highest increase in dentin permeability, followed by sodium perborate with 20% hydrogen peroxide. The 27% carbamide peroxide provided the lowest results and showed statistical similarity to the control group. On basis of these findings, it may be concluded that, among the tested intracoronal bleaching agents, 37% carbamide peroxide presented an optimized overall performance in increasing dentinal permeability.

Alteraçäo da temperatura radicular externa durante o preparo para contençäo intra-radicular / Temperature changes on the external root during post space preparation

O objetivo deste trabalho foi comparar in vitro a alteraçäo de temperatura na superfície radicular externa durante o preparo para contençäo intra-radicular utilizando 4 técnicas de remoçäo da guta-percha: condensadores aquecidos, brocas de Peeso, Gates-Glidden e Largo, em 40 dentes pré-molares inferiores (unirradiculares) tratados endodonticamente. Experimento foi realizado em uma câmara com temperatura controlada em torno de 26ºC. Para a remoçäo da guta-percha do interior dos canais, foram calculados dois terços do comprimento da raiz, deixando em torno de 4 mm de obturaçäo apical. As mediçöes da temperatura radicular externa foram realizadas com um termopar acoplado a um multímetro e efetuadas em 3 regiöes: cervical (em torno de 3 mm abaixo da junçäo cemento-esmalte), média e apical...

Evaluation of the antimicrobial activity of three irrigating solutions in teeth with pulpal necrosis / Análise da atividade antimicrobiana de três soluções irrigantes em dentes com necrose pulpar

The antimicrobial activity of 0.4 percent papaine gel (FCF-USP), an antibacterial product derived from 3.3 percent castor oil (IQSC-USP), and 0.5 percent sodium hypochlorite (FORP-USP) was evaluated in teeth with radiographically visible pulpal necrosis and periapical lesion in vivo. After cavity access, under aseptic conditions, a first harvesting was performed. The 3 irrigating solutions were used for biomechanical preparation. After 72 hours, a second harvesting was performed, also under aseptic conditions. The number of colony forming units (cfu) was counted with a stereomicroscope under reflected light. Castor oil and 0.5 percent sodium hypochlorite presented similar antimicrobial activities for the reduction of the anaerobe number, S. mutans and streptococci; however, the papaine gel showed lower activity. We conclude that both castor oil and sodium hypochlorite are effective as antimicrobial agents and can be used in the treatment of root canals with pulpal necrosis

Evaluation of the anatomical alterations of lower molars mesial root's apical third / Avaliaçäo das alteraçöes anatômicas do terço apical da raiz mesial de molares inferiores

A presente pesquisa analisa in vitro as alteraçöes anatômicas dos 4 mm apicais de 68 raízes mesiais de molares inferiores permanentes humanos, utilizando-se de microscópio esterioscópio. Cada raiz foi incluida em bloco de resina acrílica autopolimerizável, cortada transversalmente à partir de 1 mm apical obtendo-se 4 cortes em sentido cervical. Os resultados demonstraram a complexidade anatômica do terço apical da raiz mesial dos molares inferiores, com a presença de um ou dois canais radiculares. Quando da presença de dois canais radiculares estes podem apresentar-se totalmente independentes em toda extensäo da raiz ou unirem-se em diferentes níveis para terminar em canal único. Verificou-se presença de istmo entre os canais mesio-vestibular e mesio-lingual. Em raízes com canal único, obersvou-se a alteraçäo da forma do canal a medida que se aproxima do extremo apical

Utilizaçäo de duas técnicas alternativas para localizaçäo do forame apical em endodontia: avaliaçäo clínica e radiográfica / The use of two alternative techniques to locate the root apex endodontic treatment: a clinical and radiographic study

Uma das dificuldades durante o tratamento endodôntico é a determinaçäo do comprimento de trabalho, devido às limitaçöes impostas pela imagem radiográfica. Muitas técnicas têm sido desenvolvidas com o intuito de facilitar a execuçäo da odontometria durante o tratamento endodôntico. Nosso objetivo foi comparar clinicamente a eficácia de dois métodos auxiliares na odontometria: a tela milimetrada e o localizador apical eletronico (APIT, Osada Japäo). Os resultados foram concordantes em 76,47 por cento dos casos quando se tratava de dentes com polpa vital, e em dentes com polpa em estado necrótico os resultados foram concordantes em 83,64 por cento dos casos. O APIT näo foi eficiente na determinaçäo do comprimento radicular somente nos canais obliterados ou com ápices que apresentavam grandes reabsorçöes...

Microdureza de amálgama: efeito da brunidura pós-escultura e da brunidura pré e pós-escultura / Amalgam micro-hardness: the effect of post-carved burnishing and that of pre and post-carved burnishing

Os autores estudaram o efeito de duas técnicas de brunidura (brunidura pós-escultura e brunidura pré e pós-escultura) sobre a microdureza do amálgama, obtido de 3 diferentes ligas, 24 e 168 horas após a condensaçäo. Näo houve diferença estatística entre os resultados obtidos com as diferentes técnicas de brunidura em relaçäo ao grupo controle (sem brunidura). Além disso, os resultados mostraram que a microdureza é aumentada após 168 horas e que as ligas com alto teor de cobre (Dispersalloy e Sybraloy) apresentaram maiores valores de microdureza que a liga convencional (Novo True)

Microdureza de amálgamas submetidos a polimento imediato / Amalgam microhardness submitted to immediate polishing

Foram confeccionados corpos-de-prova com cavidades restauradas com amálgama, usando 3 diferentes ligas: Sybraloy, Dispersalloy e Novo True. As restaurações foram então submetidas a polimento imediato seguindo as sugestões de NITKIN & GOLDBERG. A seguir foram levados a um microdurômetro Wolpert e feito testes de microdureza Vickers. Os resultados demonstraram ter a liga Sybraloy exibido maiores valores de dureza, enquanto as ligas Dispersalloy e Novo True mostraram ser estatisticamente iguais

Moldagem dos canais radiculares / Root canal models

A presente pesquisa analisa "in vitro" a morfologia interna de 120 incisivos e caninos superiores e inferiores humanos permanentes. Foi utilizado o acetato de vinila (Vinilite) para obter moldes da câmara e dos canais radiculares. O objetivo principal do trabalho é o de apresentar um método de moldagem simples, de fácil execução, reproduzindo detalhes das paredes dos canais radiculares. A técnica consiste na remoção de conteúdo pulpar com hipoclorito de sódio e preenchimento dos canais com vinilite na consistência pastosa através de seringa Luer-lock. A seguir os dentes são dissolvidos em ácido nítrico e obtém-se um modelo sólido dos canais radiculares. A radiografia prévia à moldagem dos canais possibilitou fazer uma análise comparativa da presença de ramificação do canal principal