Avaliação do sistema WaveOne Gold e ProTaper retratamento para remoção de guta-percha clínico / Evaluation of WaveOne Gold system and ProTaper retreatment for gutta-percha removal

Objetivo: avaliar ex vivo a quantidade de guta-percha remanescente no retratamento de canal de dentes pré-molares inferiores com único canal utilizando o sistema WaveOne Gold em comparação com o sistema de retratamento ProTaper R. Materiais e métodos: foram selecionados 52 pré-molares inferiores humanos extraídos, distribuídos aleatoriamente em 2 grupos (n=26), em função das técnicas de retratamento: sistema WaveOne Gold (grupo 1) e sistema de retratamento ProTaper R (grupo 2). Após os canais radiculares serem instrumentados e obturados com guta--percha, foram submetidos à de sobturação e ao procedimento de retratamento. Os dentes foram seccionados confeccionando uma canaleta nas faces proximais dos dentes obtendo-se duas hemi--secções radiculares, expondo, portanto, a luz do canal preparado. Todas as amostras foram codificada se fotografadas por máquina Cânon A640 acoplada ao microscópio Zeiss, com aumento de 5 vezes. As fotos foram transportadas para o programa de software Image Tool 3.0. Foi feita medição das áreas de remanescentes de material obturador no interior do canal e a medição da área total do interior do canal através das imagens da secção no computador. As medidas foram comparadas em relação a cada sistema utilizando o programa BioEstat 4.0 (teste de Mann-Whitney). Resultados:A menor porcentagem de material obturador remanescente ocorreu no sistema ProTaper Rcom diferenças significantes em relação ao sistema WaveOne Gold (p<0.01). Conclusão: o sistemaProTaper R foi mais eficaz na remoção de guta-percha em comparação com o sistema WaveOne Gold, entretanto nenhum dos sistemas removeram totalmente o material obturador do canal.

Objective: This ex vivo research study aims to evaluate ex vivo the amount of remaining gutta -perchaduring canal retreatment of lower premolars single-rooted using WaveOne Gold system compared with Protaper R system. Materials and methods: 52 mandibular premolars were selected and randoml y divided into 2 groups (n = 26), according to the retreatment techniques, which are: WaveOne Gold system(group 1) and ProTaper R system (group 2). After the root canals were instrumented and filled withgutta-percha, they underwent removal procedure. After retreatment procedure, the teeth were sectioned in the proximal surfaces resulting in two hemi-sections exposing the interior of the root canal. Allsamples were coded and photographed by A640 Canon machine attached to the microscope Zeiss withzoom in 5 times, and the photos were transported to the Image Tool 3.0. software. The evaluation wasdone by measurement of areas of remaining filling material and the total area of the interior of root canal through the images on the computer. The measurements were compared for each system using Bio-Estat 4.0 program and Mann-Whitney test. Results: The smallest percentage of remaining gutta-perchaoccurred in ProTaper Retreatment system with significant differences from the WaveOne Gold system(p <0.01).Conclusion: ProTaper R system was more effective in removing gutta-percha compared withWaveOne Gold system. However none of the both systems completely removed the filling material.

Analysis of the effect of ultrasonic agitation on the cleaning of root canals using different periods during the final irrigation

Introduction: The ultrasonic agitation was introduced as an adjuvant to conventional chemo-mechanical debridement during endodontic treatment to overcome the persistence of biofilms. Objective: To verify the cleaning of root canals irrigated with sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (EDTA), with or without an ultrasonic agitation, using different time periods and images obtained by scanning electron microscope (SEM). Material and methods: Forty mandibular incisors were cleaned, shaped and randomly divided into five groups according to the final irrigation protocol: SH10 group (ultrasonic agitation with NaOCl for 10 s), SH30 group (ultrasonic agitation with NaOCl for 30 s), SHE30 group (ultrasonic agitation with NaOCl and EDTA for 10 s), SHE90 group (ultrasonic agitation with NaOCl and EDTA for 30 s), and control group (NaOCl and EDTA without ultrasonic agitation). The teeth were prepared and analyzed by SEM at ×2000. The Kruskal-Wallis test was used with a 5% level of significance. Results: For the cervical and medial thirds, there was no statistically significant difference in cleaning among the protocols used (p > 0.05). For the cleaning of the apical third, SHE90 group demonstrated a significant difference (p < 0.05), as compared to the control and SH10 groups. Conclusion: For the final irrigation, an ultrasonic agitation with NaOCl and EDTA for 30 s allowed a better cleaning of the debris in the apical third of the root canal.

Efficiency and effectiveness evaluation of three glass fiber post removal techniques using dental structure wear assessment method.

Aim: This study evaluated the efficiency and effectiveness of three glass fiber post removal techniques. Materials and Methods: Forty-five extracted maxillary teeth were endodontically treated and cross-sectioned in thirds. Presence of cementing agent and dental structure wear were assessed by analyzing images taken before luting of glass fiber post and after removal procedure. Teeth were divided into 3 groups: Group 1 - diamond bur + Largo reamer; Group 2 - ultrasonic insert; Group 3 - carbide bur + ultrasonic insert. Time spent on removal procedures, dental structure wear and amount of remaining cement agent were recorded and results submitted to ANOVA, Kruskal Wallis and Tukey-Kramer tests. Results: Group 1 - 16'46", 33.33% and 6.99%; Group 2 - 12'31", 40% and 7.86%; and Group 3 - 10'24", 80% and 8.14%. Group 3 presented the most effective removal of glass fiber posts. Conclusion: There was no significant difference in efficiency among the evaluated techniques.

Influência do tratamento e do retratamento endodóntico na resistência adesiva de pinos de fibra de vidro / Influence of endodontic treatment and retreatment on the bond strength of fiber-glass post

O espaço preparado para pino após um retratamento endodôntico pode estar sujeito a maior quantidade de smear layer, em comparação com a quantidade de resíduos produzidos no tratamento inicial, já que nenhum protocolo de retratamento é capaz de garantir completa remoção de guta-percha e cimento obturador das paredes dos canais radiculares. Este estudo avaliou a resistência adesiva in vitro de pinos de fibra de vidro cimentados em dentes submetidos ao retratamento endodôntico, em comparação aos cimentados em dentes tratados endodonticamente. Quarenta canais de raízes bovinas foram instrumentados e obturados. As amostras foram divididas aleatoriamente em 2 grupos, sendo que as raízes do Grupo I foram preparadas para pino imediatamente depois de obturadas. As raízes do Grupo II tiveram as embocaduras dos canais seladas com o cimento restaurador temporário por um período de 30 dias, com posterior retratamento endodôntico e preparo para pino imediato. Pinos de fibra de vidro foram cimentados com cimento resinoso RelyX U100 nas raízes dos dois grupos, que permaneceram armazenadas por 7 dias para posterior realização do teste push-out, com resultados submetidos à análise de variância e ao teste de Tukey. A comparação das médias de força entre os grupos testados revelou que a média de força do Grupo I foi significativamente maior que a do Grupo II (p<0,01). O padrão de fratura foi predominantemente adesivo (interface dentina-cimento resinoso) em ambos os grupos. Pode-se concluir que há diminuição na resistência adesiva de pinos de fibra de vidro cimentados em dentes submetidos ao retratamento endodôntico.

The space prepared for a post after endodontic retreatment could be subject to a greater amount of debris compared to that produced during initial treatment because no retreatment protocol is capable of ensuring complete removal of gutta-percha and sealer from the root canal walls. This study assessed the in vitro bond strength of glass fiber posts cemented in teeth submitted to endodontic treatment, in comparison to posts cemented in teeth submitted to endodontic retreatment. Fourty roots of bovine teeth were instrumented, obturated and then randomly divided into two groups. In Group I, the gutta-percha was partially removed and the roots were prepared for post placement immediately after obturation. In Group II, the roots were sealed with temporary restorative cement and stored for a period of 30 days, after which they were endodontically retreated and immediately prepared for post preparation. Glass fiber posts were cemented with RelyX U100 resin cement in the roots of both groups, which remained stored during 7 days for subsequent push-out testing a and Tukey’s test. Comparison between groups revealed that the mean bond strength for Group I was significantly higher than that for Group II (p < 0.01). The pattern of bond failure was predominantly adhesive (dentin-resin cement interface) for both groups. It could be concluded that there was a reduction in the bond strength of glass fiber posts cemented in teeth submitted to endodontic retreatment

Lack of correlation between tubular dentine cement penetration, adhesiveness and leakage in roots filled with gutta percha and an endodontic cement based on epoxy amine resin

Objective: To analyze possible correlations among tubular dentine cement penetration, adhesiveness and apical leakage in fillings performed with gutta percha and an endodontic cement based on epoxy amine resin. Material and Methods: Sixty similar, extracted human mandibular central incisors were irrigated, instrumented and filled following the same protocol. First, apical leakage was quantified by fluid filtration tests. Then, these same specimens were sectioned for analysis of tubular dentine cement penetration and the middle thirds were submitted to push-out tests to analyze the adhesiveness of the fillings. Results: In brief, the means and standard deviations with a confidence interval of 95% were as follows: tubular dentine cement penetration (8.875±4.540), adhesiveness (4.441±2.683) and apical leakage (0.318±0.215). The data were confronted using the Pearson's test (P>0.05), and it was possible to prove that there was no correlation between (1) tubular dentine cement penetration and apical leakage (r2: 0.08276), (2) tubular dentine cement penetration and adhesiveness (r2: -0.2412) and (3) adhesiveness and apical leakage (r2: 0.1340). Conclusion: After analysis of these data, it could be observed that there exists no correlation among the variables analyzed in this study. .

Analysis of the preparation obtained by three techniques of root canal instrumentation using computed tomography / Análise do preparo obtido por três técnicas de instrumentação do canal radicular através de tomografia computadorizada

Objective: Use computed tomography to compare three methods of root canal instrumentation. Methods: Thirty mandibular molar mesiobuccal canals were divided in three groups according to instrumentation technique: Group 1 - hand instrumentation with balanced force technique; Group 2 - Protaper Universal rotary system following manufacturer's instructions; and Group 3 - Protaper Universal rotary system and Gates-Glidden drills. Teeth were evaluated by computed tomography before and after preparation at three axial cuts: 3mm, 5mm, and 7mm from the root apex. Data were subjected to statistical analysis using the F, Chi-Square, Likelihood Ratio Chi-Square, and Mantel-Haenszel Chi-Square tests. Results: Group 3 showed significantly greater dentin removal with no tendency towards mesial or distal canal transportation, compared with Groups 1 and 2. Also, Group 3 required the least amount of time for instrumentation. Conclusion: Association of rotary instrumentation and Gates-Glidden drills is a safe and effective technique for root canal preparation.

Objetivo: Comparar o preparo de canais radiculares através de tomografia computadorizada. Métodos: Trinta canais mésio-vestibulares de molares inferiores foram divididos em 3 grupos, de acordo com a técnica de instrumentação a ser utilizada: Grupo 1 - instrumentação manual, utilizando-se de movimentos de forças balanceadas; Grupo 2 - Sistema Protaper Universal de instrumentação rotatória, conforme protocolo do fabricante; Grupo 3 - Sistema Protaper Universal de instrumentação rotatória associada a brocas de Gates- Glidden para pré-alargamento cervical. Os dentes foram submetidos à tomografia computadorizada antes e após o preparo, e a análise das imagens foi feita através de cortes axiais a 3mm, 5mm e 7mm do ápice radicular. Os dados foram submetidos a análise estatística utilizando testes paramétricos (para as variáveis tempo e desgaste de dentina) e não-paramétricos (para a variável sentido do desvio). Resultados: Os resultados mostraram uma tendência significativa do grupo 3 a desgastar mais dentina quando comparado aos grupos 1 e 2. O grupo 1 desgastou significantemente mais dentina para o sentido distal e o grupo 2 desgastou significantemente mais para o sentido mesial. O grupo 3 não apresentou tendência de sentido de desgaste. O tempo despendido foi menor no grupo 3, seguido pelo grupo 1 e 2. Conclusão: Pôde-se concluir que a associação das brocas de Gates-Glidden ao Sistema Protaper Universal promoveu um preparo adequado de maneira segura e, a tomografia computadorizada foi um método adequado para a análise do preparo de canais radiculares.

Lack of correlation between obturation limits and apical leakage

The aim of this paper was to evaluate a possible correlation between obturation limits and leakage. Thirty-six extracted human mandibular incisors were used, characterized by straight and single canals, non-anatomical complexities, absence of previous endodontic treatment, complete root formation and patent foramen. For standardization of the specimens for the leakage analysis, foraminal instrumentation was performed up to a Flexofile #25 (Dentsply-Maillefer, Ballaigues, Switzerland). All specimens were instrumented and filled following the same protocol, and the obturation limits were measured using Axiovision 4.5 Software (Carl Zeiss Vision, Hallbergmoos, Germany). The specimens were then separated into three groups (n = 12) according to the following variables: Group I - obturation limits ranging from 0 mm to 0.76 mm of the main apical foramen. Group II - obturation limits ranging from 0.77 mm to 0.98 mm of the main apical foramen. Group III - obturation limits ranging from 0.99 mm to 1.68 mm of the main apical foramen. Apical leakage was quantified by fluid filtration. The analyses were confronted using Pearson's test (p > 0.05). Groups I, II and III showed Pearson correlation values (r2) of -0.152, -0.186 and 0.058, respectively. No correlation was found between the obturation limits and apical leakage.

Comparação entre os sistemas rotatórios Pathfile + Protaper Universal e Twisted Files quanto à preservação da morfologia e ao tempo de trabalho despendido na preparação de canais curvos / Comparison of preparation time and ability to maintain canal morphology in curved canals: Pathfile + Protaper Universal versus Twisted Files

Introdução: Instrumentos rotatórios em níquel-titânio (NiTi) reduzem erros processuais e o tempo requerido para a preparação do canal radicular. Objetivo: Comparar dois sistemas de instrumentação rotatória NiTi - Pathfile + ProTaper Universal e Twisted Files - quanto à capacidade de preservação da morfologia do canal e quanto ao tempo de trabalho necessário para a preparação de canais curvos. Material e Método: Os canais mesiais de 32 molares inferiores humanos (com ângulos de curvatura entre 20 e 40 graus) foram selecionados para o estudo. As amostras foram divididas aleatoriamente em dois grupos de 16 canais. Os preparos foram realizados por um Endodontista, utilizando-se a combinação dos instrumentos rotatórios Pathfile e ProTaper Universal (grupo PT) e os instrumentos rotatórios Twisted Files (grupo TF). Três Endodontistas analisaram imagens com a técnica da dupla radiografia digital, pré e pós-instrumentação, para avaliar se ocorreu transporte apical e/ou aberrações na morfologia dos canais. Por meio de uma análise computadorizada e com o auxílio de magnificação, as imagens inicial e final do canal radicular foram comparadas por meio de sua sobreposição. O teste de odds ratio foi utilizado para a comparação dos níveis de preservação da morfologia do canal, e ANOVA, complementada pelo teste de Tukey, foi utilizada para a comparação dos tempos de preparo. O nível de significância adotado foi de 5%. Resultado: Ocorreram desvios na trajetória do canal em ambos os grupos, mas a diferença entre estes não foi significativa. O tempo de trabalho requerido pela combinação dos sistemas Pathfile + ProTaper Universal foi significativamente maior do que o requerido pelo sistema Twisted Files. Conclusão: Os dois sistemas apresentaram performances semelhantes em relação à preservação da trajetória do canal; no entanto, o tempo de trabalho requerido pelo sistema Twisted Files foi menor.

Introduction: Nickel-titanium (NiTi) rotary instruments reduce procedural errors and the time required for root canal preparation. The aim of this study was to compare two rotary NiTi instrumentation systems-Pathfile + ProTaper Universal versus Twisted Files-as to their ability to maintain original canal morphology and the time they require to prepare curved root canals. Material and Method: The mesial canals of 32 human mandibular molars (with curvature angles between 20 and 40 degrees) were selected for the study, and divided at random into two groups of 16 canals each. The canals were prepared by an endodontist using either the combination of Pathfile and ProTaper Universal instruments (Group PT) or Twisted Files (Group TF). The double digital radiograph technique, pre- and post-instrumentation, was used by three endodontists to assess whether apical transportation and/or aberration in root canal morphology occurred. The initial and final images of the root canals were compared by superimposition through computerized analysis and with the aid of magnification. The odds ratio test was used to compare root canal morphology preservation, and ANOVA complemented by Tukey's test was used to compare preparation times. The significance level was set at 5%. Result: Deviation in root canal trajectory occurred in both groups, although the differences were not significant. The preparation time required by the Pathfile + ProTaper Universal combination was significantly longer than that required by the Twisted Files system. Conclusion: Both systems showed similar performances regarding the ability to maintain original root canal morphology; however, the preparation time required by the Twisted Files system was shorter.

Lack of pulp sensitivity in maxillary canines submitted to orthodontic traction: a retrospective clinical study

Introduction : Orthodontic movement may cause a great number of tissue alterations in the dental pulp. However, these changes may not be entirely recognized owing to the difficulty in simulating clinical situations. Objective : The aim of this study was to clinically assess the incidence of negative pulp sensitivity to cold among maxillary canines in infraocclusion submitted to orthodontic traction. Material and methods: Two study groups were selected: an experimental group, comprising 32 canine teeth with complete root formation that had been submitted to orthodontic traction, and a control group, comprising 32 canine teeth with complete root formation that had never been submitted to any orthodontic movement. Results: Fourteen teeth from the experimental group showed lack of pulp sensitivity, whereas only one tooth from the control group showed negative pulp sensitivity. Fischer's exact test revealed a significant difference between the groups (p < 0.05). Conclusion: In conclusion, the teeth that had been submitted to orthodontic traction were more likely to lack sensitivity than those that had not been submitted to the same procedure.

Viabilidade de dentes decíduos artificiais para mensuração eletrônica do comprimento de trabalho dos canais radiculares / Viability of artificial primary teeth for electronic working length determination

Objetivo: viabilizar a utilização de dentes decíduos artificiais com polpa e condutos radiculares em pesquisas ôin vitroõ com o uso do localizador apical Root ZX II. Método: foram selecionados 20 molares decíduos artificiais que apresentavam três condutos radiculares e não apresentavam trincas, fraturas ou defeitos de fabricação. Foi feita abertura coronária, acesso aos condutos, patência foraminal e mensuração dos canais radiculares por meio de método visual e eletrônico. A mensuração no método visual (G1- controle) foi realizada introduzindo a lima no ponto da cúspide de referência até a lima atingir o forame apical. No método eletrônico (G2- experimental), os dentes foram inseridos em alginato e a lima inserida no canal radicular até o localizador indicar o ápice. As mensurações foram realizadas em triplicata. As médias das medidas em milímetros foram submetidas ao teste de correlação de Pearson no programa Biostat 2.0 com valor de significância de 5%. Resultados: as medidas observadas pelo método eletrônico apresentaram correlação com os resultados obtidos pelo método visual (r Pearson = 0,9490; p = 0,0000). Conclusão: os dentes decíduos artificiais podem ser utilizados em pesquisas ôin vitroõ com o localizador apical Root ZX II...

Objective: To allow the use of artificial primary teeth with pulp and root canals for in vitro studies with the Root ZX II electronic apex locator.Method: Twenty artificial primary molars with three root canals and no cracks, fractures or fabrication defects were selected. After coronal opening, access to the canals was gained, foramen patency waschecked and direct and electronic working length determination was performed. For direct visual working length determination (Group 1 ?control), the file was introduced into the canal from the reference cusp until its tip was visible at the apical foramen. For the electronic working length determination (Group 2 ? experimental), the teeth were embedded in alginate and the file was introduced into the canal until the electronica locator indicated the apex. The measurements were made in triplicate. The means (in mm) were subjected to Pearson?s correlation coefficient test using the Biostat 2.0 software. The significance level was set at 5%.Results: The electronic measurements correlated with the direct visual measurements (r=0.9490; p=0.0000).Conclusion: Artificial primary teeth can be used for in vitro studies with the Root ZX II electronic apex locator...

Analysis of the instrumentation time and cleaning between manual and rotary techniques in deciduous molars

Introduction: The rotary instrumentation provides shorter instrumentation time with greater comfort for the patient but few studies have been conducted on primary teeth. Objective: his study compared the cleaning ability and instrumentation time between manual and rotary techniques in deciduous molars. Material and methods: a total of 15 molars were selected, submitted to coronal opening and root canal filled with India ink. After 48 hours, the teeth were divided into three groups: G1 - manual instrumentation with K files, G2 - rotary system Endowave, and G3 - rotary system ProTaper. After instrumentation, the teeth were sectioned and three blinded examiners evaluated the root canal cleaning. The mode of scores of examiners was analyzed by the Kruskal-Wallis test. The instrumentation time was recorded and the results were statistically analyzed by ANOVA.Results: the ProTaper system presented shorter instrumentation time compared to manual instrumentation (p = 0.0339). Endowave system did not present statistically significant difference in the instrumentation time compared to the other groups. There were no significant differences between groups concerning the ability of root canal cleaning (p = 0.6188). Conclusion: ProTaper system revealed shorter treatment time and similar cleaning ability compared to the other techniques, thus being indicated for deciduous teeth.

Radix entomolaris - A case report

Introduction: A comprehensive knowledge on the root canal anatomy is a basic prerequisite for the endodontic treatment successful. Mandibular molars may have an additional root located lingually (radix entomolaris) or buccally (radix paramolaris). In the literature, this anatomy variation is considered rare in Caucasian populations. Awareness and understanding of the presence of unusual external and internal root canal morphology contributes to the successful outcome of the root canal treatment. Objective and case report: The purpose of this study was to report a clinical case of successful endodontic treatment in a mandibular molar with pulp necrosis and characterized as radix entomolaris in which the use of magnification and ultrasonic tips (the “microsonics concept”) was fundamental to the management of the variations in the internal anatomy. Conclusion: A better understanding of the root canal morphology is essential for endodontic treatment success, as well as the use of technologic advancements in Endodontics including computed tomography, ultrasonic tips and the operating microscope.

Assessing apical transportation in curved canals: comparison between cross-sections and micro-computed tomography

The aim of this study was to compare two methods of assessing apical transportation in curved canals after rotary instrumentation, namely, cross-sections and micro-computed tomography (µCT). Thirty mandibular molars were divided into two groups and prepared according to the requirements of each method. In G1 (cross-sections), teeth were embedded in resin blocks and sectioned at 2.0, 3.5, and 5.0 mm from the anatomic apex. Pre- and postoperative sections were photographed and analyzed. In G2 (µCT), teeth were embedded in a rubber-base impression material and scanned before and after instrumentation. Mesiobuccal canals were instrumented with the Twisted File (TF) system (SybronEndo, Orange, USA), and mesiolingual canals, with the EndoSequence (ES) system (Brasseler, Savannah, USA). Images were reconstructed, and sections corresponding to distances 2.0, 3.5, and 5.0 mm from the anatomic apex were selected for comparison. Data were analyzed using Mann-Whitney's test at a 5% significance level. The TF and ES instruments produced little deviation from the root canal center, with no statistical difference between them (P > 0.05). The canal transportation results were significantly lower (0.056 mm) in G2 than in G1 (0.089 mm) (p = 0.0012). The µCT method was superior to the cross-section method, especially in view of its ability to preserve specimens and provide results that are more closely related to clinical situations.

Comparison between electronic and radiographic method for the determination of root canal length in primary teeth

Introduction: There are few researches in literature that mention the use of the apex locator in deciduous teeth and working length is obtained through radiographies. Objective: The purpose of this research was to compare the radiographic and the electronic method to obtain the working length in deciduous molars. Material and methods: Twelve molar teeth were used. The specimens in the visual method had their root length measured through the passive insertion of a 10 K-file with a silicone stop within root canal until its tip was seen at the apical foramen. The working length was measured through radiographs or using the apex locator Root ZX II. The mean between the examiners was submitted to the variance analysis (ANOVA). Results: Statistically significant differences were found between the visual method and the radiographic method (p < 0.001). There was no significant difference between the working length measurements in visual method and those obtained with the apex locator (p = 0.1319). Conclusion: The apex locator is indicated as a clinical implementation for endodontic treatment in primary teeth.

Evaluation of cleaning efficacy of a nickel-titanium rotary system, with or without 17% EDTA passive ultrasonic activation: a scanning electron microscopic study

Introduction: The goal of endodontic instrumentation is to promote root canal cleaning and shaping to prepare it for the subsequent three-dimensional filling. Objective: The aim of this study was to evaluate, ex vivo, root canal cleaning ability executed by nickel-titanium rotary system instrumentation and this same system plus ultrasound passive activation of 17% EDTA, through SEM. Material and methods: Seventy upper second single-rooted human bicuspids were used. All teeth presented a single root canal, flattened towards buccal-palatal direction. The teeth were randomly separated into 3 groups. Group 1 (n = 30), had the canals instrumented by using the original operative sequence of ProTaper Universal System, up to instrument #F3. In this group, 5 ml of 5.25% sodium hypochlorite was employed as irrigant, every each instrument change. After group 1 instrumentation, root canals were irrigated with 5 ml of 17% EDTA, which was kept inside the canal for 3 minutes. Next, a final irrigation with 5 ml of 5.25% NaOCl was performed to remove the smear layer in suspension. Group 2 (n = 30) had the canals instrumented by the same system and up to the same instrument size. It was used 5.0 ml of 5.25% NaOCl as irrigant substance every each instrument change. In group 2, however, 17% EDTA (5 ml) was applied through ultrasonic passive activation for 1 minute, and then leaving the substance for 2 minutes within root canal.A final irrigation and with 5.25% NaOCl was also performed. Group 3 (n = 10) was the control group, where the canals were not instrumented and irrigation was executed with saline solution. After that, the teeth were cut into their long axis, metalized and taken for SEM analysis, at x2000 magnification. Each tooth's cervical, middle and apical thirds were observed. The cleaning quality of root canal's walls was observed by the images analyzed by three examiners. Results: Data were statistically analysed by analysis of variance and Tukey test, with a significance level of 5%. The control group showed an average score of the presence of smear layer of 3.41; group 1 (ProTaper) of 2.34; and the group 2 (ProTaper+Ultrassound) of 0.60. Conclusion: None of the studied preparation techniques promoted the total cleaning of the root canal walls. The addition of the ultrasound passive activation, after rotary instrumentation, promoted an increase of the smear layer removal, improving the cleaning of root canal wall. The apical third obtained the smallest cleaning rate, regardless of the technique employed.

Comparison of MTA Fillapex radiopacity with five root canal sealers

Introduction: The endodontic sealer is a filling material whose physicochemical properties are mandatory for the achievement of endodontic therapy final goal. An ideal endodontic sealer should have some properties, including radiopacity. Objective: This study compared MTA Fillapex™ radiopacity with the radiopacity of five others endodontic sealers: Endométhasone-N™, AH Plus™, Acroseal™, Epiphany SE™ and RoekoSeal™. Material and methods: Five cylindrical samples of each sealer were used, constructed with the aid of a matrix. On an occlusal film, a sample of each sealer was placed along with an aluminum stepwedge and five radiographic shots were taken. The radiographic images were digitized and each sample's gray scales were compared with each shade of the aluminum stepwedge, by using software. Results: The results, in decreasing order of radiopacity, were: AH Plus™ was statistically the most radiopaque sealer (9.4 mm Al), followed by Epiphany SE™ (7.8 mm Al), MTA Fillapex™ (6.5 mm Al), RoekoSeal™ (5.8 mm Al), Endométhasone-N™ (4.5 mm Al), and Acroseal™, the least statistically radiopaque (3.5 mm Al). Conclusion: It can be concluded that MTA Fillapex™ was the third most radiopaque sealer among all tested sealers. Also, MTA Fillapex™ has the radiopacity degree in agreement with ADA specification No. 57 (1983).

Tratamento endodôntico de incisivo superior geminado / Endodontic treatment of a geminated maxillary incisor

INTRODUÇÃO: A geminação é uma anomalia que ocorre por conta da tentativa de dois dentes se desenvolverem a partir de um único germe, resultando em um elemento com tamanho maior que o normal, porém com apenas um canal radicular, e que, em decorrência de suas características e peculiaridades, exige atenção quando da realização do tratamento endodôntico. OBJETIVO E RELATO DE CASO: Este estudo tem como objetivo apresentar o tratamento endodôntico de um incisivo central superior portador de geminação. CONCLUSÃO: O planejamento das etapas do tratamento baseado num atento exame clínico e radiográfico faz-se indispensável para a obtenção do sucesso no tratamento endodôntico de dentes geminados.

INTRODUCTION: Gemination is a tooth anomaly caused when a single tooth bud attempts to divide. This results in a tooth with a size greater than normal, but with only one root canal. Therefore, due to its features and singularities, this geminated tooth demands careful attention for endodontic treatment OBJECTIVE AND CASE REPORT: The purpose of this case report is to describe the endodontic treatment of a geminated maxillary central incisor. CONCLUSION: A good planning of all treatment stages, based on a careful clinical and radiographic examination, it is essential to reach the success in the endodontic treatment of geminated teeth.

O conceito microsonics: primeiro molar superior com cinco canais - relato de caso / The microsonics concept: maxillary first molar with five root canals - case report

INTRODUÇÃO: A complexidade da anatomia do sistema de canais radiculares constitui um desafio contínuo para o endodontista. A morfologia do primeiro molar superior permanente contém inúmeras variações, referentes ao número de raízes, de canais e à sua localização. Assim, o sucesso do tratamento endodôntico está relacionado ao domínio da anatomia. OBJETIVO E RELATO DE CASO: Este estudo teve como objetivo apresentar o tratamento endodôntico de um primeiro molar superior com pulpite irreversível em que o microscópio operatório associado aos insertos ultrassônicos foi fundamental para o domínio da anatomia. Localizaram-se cinco canais, sendo dois deles mesiovestibulares, dois distovestibulares e um palatino. CONCLUSÃO: O conhecimento da anatomia, bem como de suas diversidades, aliado ao uso de tecnologias,como microscópio operatório, ultrassom e tomografia computadorizada, faz com que o sucesso no tratamento endodôntico aumente.

INTRODUCTION: The complex anatomy of the root canal system is a continuous challenge for endodontists. Permanent maxillary first molars may present several morphological variations, both in the number and location of roots and canals. Therefore, the success of the endodontic treatment depends on an accurate knowledge of root canal anatomy. OBJECTIVE AND CASE REPORT: This study describes the endodontic treatment of a permanent maxillary first molar diagnosed with irreversible pulpitis. The technology employed to evaluate the case, namely dental operating microscope associated with ultrasonic tips, was essential to delineate the anatomic characteristics of the tooth to be treated, revealing the presence of five root canals: two mesiobuccal, two distobuccal, and one palatal canal. CONCLUSION: The knowledge of the tooth anatomy, as well as its possible anatomic variations, combined with the use of current technologies, such as dental operating microscope, ultrasonic tips, and computed tomography, help to enhance the endodontic treatment success.

Análise comparativa de dois localizadores apicais eletrônicos na definição do comprimento de trabalho na terapia endodôntica: estudo in vitro / Comparative analysis of two electronic apex locators in working length determination at endodontic therapy: an in vitro study

Introdução: A terapia endodôntica é cercada de etapas que, quando bem realizadas individualmente, contribuem para o sucesso. Uma delas é a odontometria, que busca a mensuração do comprimento real do dente, limitando a ação do operador nos procedimentos de instrumentação e obturação, com vistas a evitar danos aos tecidos periapicais e favorecer o reparo da área. Objetivo: Avaliar in vitro a confiabilidade de dois localizadores apicais eletrônicos (Root ZXII® e Propex II®) na obtenção do comprimento de trabalho comparados às medidas visuais. Material e métodos: Realizaram-se acesso cirúrgico e preparo cervical em 40 dentes humanos unirradiculares, e uma lima tipo Kerr #10 foi introduzida até sua extremidade ser observada na saída foraminal com aumento de 8 vezes. Então, posicionou-se o stop de borracha no bordo incisal e mediu-se esse comprimento com uma régua endodôntica milimetrada, obtendo-se o comprimento real do dente (CRD). Os dentes foram inseridos em uma base experimental composta de esponja vegetal embebida em solução de cloreto de sódio a 0,9%. Efetuaram-se as medições eletrônicas tendo como critério a localização do forame de acordo com a marcação de ápice dos aparelhos Root ZXII® e Propex II®. Resultados: O localizador apical Root ZXII® obteve índice de acerto de 93%, e o Propex II®, de 90%. Não houve diferença estatística entre os aparelhos testados (p = 0,05). Conclusão: Ambos os aparelhos demonstraram índices de acerto aceitáveis para a sua utilização na clínica.

Introduction: Endodontic treatment comprises individual steps that should be effectively performed in order to achieve therapeutic success. Among these steps is the determination of the real tooth length, which prevents damage to the periapical tissues during instrumentation and obturation, due to restrict the operator action, favoring tissue repair. Objective: The present study aimed to evaluate in vitro the reliability of two electronic apical locators (Root ZX II® and Propex II®) in working length determination, compared to direct visual measurement. Material and methods: Forty single-rooted human teeth were selected; the pulp chamber was accessed and a size 10 Kerr file was inserted into the canal until its tip was visible at the apical foramen with x8 magnification. At this point, a rubber stop was placed on the file, at the incisal edge, and this length was measured with an endodontic ruler, therefore, recording the real tooth length (RTL). Then, the teeth were embedded in a vegetable sponge (loofah) base, soaked in saline solution. Electronic measurements were carried out using Root ZX II® and Propex II® locators, until an ?Apex? reading was observed. The measurements obtained by the different methods were compared. Results: Root ZX II® apical locator showed 93% of correct readings, while Propex II® locator was correct in 90% of the measurements. No statistically significant difference was observed between the two apex locators tested (p = 0.05). Conclusion: Both apex locators showed an acceptable percentage of correct readings and, therefore, may be recommended for clinical use.

Comparação da taxa de sucesso de quatro soluções anestésicas no bloqueio do nervo alveolar inferior em pacientes com pulpite irreversível. Estudo prospectivo, randomizado, duplo-cego

Objetivo: comparar a eficácia de quatro soluções anestésicas para o bloqueio do nervo alveolar inferior (BNAI) em pacientes com pulpite irreversível. Métodos: esse estudo prospectivo, randomizado e duplo-cego incluiu 60 pacientes adultos que compareceram ao serviço de atendimento de urgência da PUC-Campinas, São Paulo, Brasil. Os pacientes foram divididos aleatoriamente em quatro grupos,com 15 indivíduos cada, e receberam o bloqueio do nervo alveolar inferior: Grupo ART - 2 tubetes de articaína 4% com epinefrina 1:100.000; Grupo LID - 2 tubetes de lidocaína 2%com epinefrina 1:100.000; Grupo PRI - 2 tubetes de prilocaína 3% com felipressina 0,03U.I.; e Grupo MEP - 2 tubetes de mepivacaína 2% com epinefrina 1:100.000. Iniciou-se o acesso cirúrgico após 10 minutos do bloqueio do nervo alveolar inferior e o paciente foi instruído a relatar qualquer sensibilidade ou dor que sentisse durante o procedimento.O BNAI foi considerado bem-sucedido quando o procedimento de acesso e instrumentação foi realizado sem dor para o paciente. Se o paciente sentisse dor, o procedimento era interrompido e a anestesia considerada como insucesso.Resultados: foi utilizado o teste estatístico qui-quadrado para analisar os resultados (α=5%) e não houve diferença significativa (p>0,05) na taxa de sucesso do bloqueio do nervo alveolar inferior entre os grupos: ART = 53,33%, PRI = 46,66% e MEP = 53,33%. Porém, a taxa no grupo LID foi estatisticamente inferior (20%) à dos demais grupos(p<0,05). Conclusão: nenhuma das soluções anestésicas apresentou um índice de sucesso aceitável para o bloqueio do nervo alveolar inferior em pacientes com pulpite irreversível em molares inferiores. A solução de lidocaína 2% com epinefrina 1:100.000 apresentou o pior resultado, quando comparado ao dos demais grupos