Efeito de diferentes protocolos de irrigação final na remoção da smear layer / Effect of different protocols of final irrigation on smear layer removal

Objetivo: esse estudo avaliou o efeito de protocolos de irrigação final, associados ao uso de EDTA e QMix, na remoção de smear layer. Métodos: foram utilizados 40 dentes humanos com canal único. Os canais foram instrumentados com sistema ProTaper Universal SX-F3. As substâncias químicas utilizadas durante o preparo foram hipoclorito de sódio a 5,25% (NaOCl) ou clorexidina a 2% (CHX) gel. Terminado o preparo, os dentes foram divididos em oito grupos, de acordo com os irrigantes: G1) NaOCl 5,25% + EDTA 17% + NaOCl 5,25%; G2) NaOCl 5,25% + EDTA 17% + água destilada (AD); G3) NaOCl 5,25% + QMix + NaOCl 5,25%; G4) NaOCl 5,25% + QMix + AD; G5) CHX 2% gel + EDTA 17% + CHX 2% solução; G6) CHX 2% gel + EDTA 17% + AD; G7) CHX 2% gel + QMix + CHX 2% solução e G8) CHX 2% gel + QMix + AD. As amostras foram avaliadas por microscopia eletrônica de varredura ambiental, antes e após os protocolos de irrigação final. As imagens foram classificadas por escores, em relação à presença de smear layer, e os dados foram analisados pelos testes de Kruskal-Wallis e de Mann-Whitney. Resultados: o G1 mostrou os melhores resultados em relação à remoção de smear layer (p < 0,05). A CHX gel 2% mostrou menor formação de smear layer, quando comparada ao NaOCl, após o preparo biomecânico; e o NaOCl apresentou melhor limpeza como irrigante final (p < 0,05). Conclusões: o NaOCl como irrigante final, combinado ao EDTA, mostrou melhor capacidade de remoção da smear layer (AU).

Introduction: This study evaluated the effect of different final irrigation protocols using EDTA and QMix on smear layer removal. Methods: The root canals of 40 single-rooted human teeth were prepared with ProTaper Universal SX - F3. The substances used were 5.25% sodium hypochlorite (NaOCl), 2% chlorhexidine gel (chlorhexidine), 2% chlorhexidine solution and distilled water. The teeth were divided into 8 groups, according to the irrigant used: G1: 5.25% NaOCl + 17% EDTA + 5.25% NaOCl; G2: 5.25% NaOCl + 17% EDTA + distilled water; G3: 5.25% NaOCl + QMix + 5.25% NaOCl; G4: 5.25% NaOCl + QMix + DW; G5: 2% chlorhexidine gel + 17% EDTA + 2% chlorhexidine solution; G6: 2% chlorhexidine gel + 17% EDTA + distilled water; G7: 2% chlorhexidine gel + QMix + 2% chlorhexidine solution; and G8: 2% chlorhexidine gel + QMix + distilled water. Samples were evaluated under environmental scanning electron microscopy (ESEM) before and after irrigation. ESEM images were classified according to smear layer scores, and the Kruskal-Wallis and Mann-Whitney tests were used for statistical analyses. Results: Group 1 had the best results for smear layer removal (p<0.05). Smear layer formation was lower when 2% chlorhexidine gel was used after cleaning and shaping than when the irrigant was 5.25% NaOCl, and 5.25% NaOCl had the best cleaning ability as a final irrigant. Conclusion: 5.25% NaOCl combined with EDTA was the best final irrigant for smear layer removal (AU).

Mandibular mesial root canal morphology using micro-computed tomography in a Brazilian population.

To assess the root canal system morphology of mandibular molars by means of micro-computed tomography, one hundred and four mandibular first molars were investigated and the following were evaluated: Vertucci's classification, the presence of lateral canals and the number of apical foramina. Mesial root canal surface area and volume were obtained by the CTAn and CTvol software. The type of root canal isthmi was classified applying the Hsu & Kim and Fan criteria. The most frequent root canal configuration was Vertucci type IV (46.2%). Lateral canals were observed in all root canal thirds and the average number of apical foramina was 3.15 ± 1.77. Regarding the presence of isthmus, Types I and II were the most prevalent, according to Hsu & Kim and Fan et al. criteria, respectively. Mesial root canals of mandibular molars showed high morphology variability.

Improved sealing ability promoted by calcium silicate-based root canal sealers

Aim: This study investigated the sealing ability produced by AH Plus (Dentsply DeTrey, Konstaz, Germany), EndoSequence BC sealer (Brasseler USA, Savannah, GA, USA), GuttaFlow (Coltène/Whaledent, Altstätten, France) and MTA Fillapex (Angelus, Londrina, Brazil). Methdos: A total of forty-six single-root human canines were prepared and randomly divided into four experimental groups (n=10): MTA Fillapex, EndoSequence BC Sealer, AH Plus or GuttaFlow. Teeth with intact crowns served as negative controls (n=3) and teeth filled with only gutta-percha served as positive controls (n=3). Teeth were mounted in a two-chamber apparatus and exposed to Enterococcus faecalis. The number of days over a 60-days period was recorded for the appearance of turbidity in the lower chamber. Kaplan-Meier method was used to estimate the survival curves. The nonparametric log-rank test was used to compare the survival curves using a significance level of 0.05. Results: The results at the end of the observation time were further analyzed by chi-square testing. All positive controls leaked within 24 h, whereas none of the negative controls leaked after 60 days. EndoSequence BC Sealer and MTA Fillapex had significant less bacterial leakage (P<0.05) than the other tested sealers. No significant difference between AH Plus and GuttaFlow was observed (P>0.05). Conclusion: In conclusion, calcium-silicate based root canal sealers promoted improved sealing ability when compared to other endodontic sealers

Effect of final irrigation protocols on push-out bond strength of an epoxy resin root canal sealer to dentin.

The purpose of the present study was to evaluate the effect of different final irrigation protocols on push-out bond strength of an epoxy resin root canal sealer to dentin. Eighty single-rooted anterior teeth were used. The root canals were partially prepared using a rotary system and the final diameter was standardised using a #5 Gates-Glidden drill prior to the push-out bond test. During chemomechanical preparation, 5.25% NaOCl or 2% CHX gel was used. For smear layer removal, 17% ethylenediaminetetraacetic acid (EDTA) or QMix 2 in 1 was applied for 3 min. As final irrigant, 1 mL of NaOCl, CHX solution or distilled water was used. On conclusion of preparation, canals were filled with gutta-percha/AH Plus sealer. Bond strength was measured by the push-out test. Data were statistically analysed by Kruskal-Wallis and Mann-Whitney U-tests. The group NaOCl/EDTA/NaOCl showed significantly higher bond strength values than other groups. In all groups, there were mainly mixed failure patterns. It can be concluded that 5.25% NaOCl proved to be the best solution for the final irrigation when combined with EDTA. The final irrigation protocols affect the push-out bond strength of AH Plus to dentin.

Biocompatibility of a self-adhesive gutta-percha-based material in subcutaneous tissue of mice.

INTRODUCTION: The purpose of this study was to evaluate the biocompatibility of a self-adhesive gutta-percha material and compare it with that of conventional gutta-percha. METHODS: Standard quantities of bioactive gutta-percha and conventional gutta-percha were directly inserted subcutaneously into the dorsal connective tissue of 30 BALB/c mice according to ISO 10993-6. After 7, 21, and 63 days each, 10 animals were euthanized, and the materials and surrounding tissue were removed. Tissue samples were subjected to histological processing resulting in 5-µm-thick slices stained with hematoxylin-eosin and Gomori trichrome stain. A grade ranging from I-IV was used to classify the inflammatory reaction. The Mann-Whitney U test with Bonferroni correction was used to compare the grade of inflammation induced by the materials at each time point. Qualitative evaluation of biocompatibility over time was also performed. RESULTS: Bioactive gutta-percha was more biocompatible than conventional gutta-percha at each time interval (P < .05). Tissue exposed to bioactive gutta-percha reached "no inflammation" (grade I) at the 21-day interval, whereas it took 63 days for the conventional gutta-percha to reach the "slight inflammation" level (grade II). CONCLUSIONS: Bioactive gutta-percha presented good tissue reaction at all time points. It may serve as an alternative to gutta-percha in terms of biocompatibility.

Avaliação do desvio apical após o preparo com sistema Protaper com e sem o uso prévio de limas PathFile / Evaluation of apical transportation in Protaper system with and without PathFile files

O presente estudo verificou se a pré-instrumentação com limas PathFile diminui a possibilidade de desvio apical durante o preparo endodôntico com limas Protaper nos canais simulados em blocos de resina. Foram confeccionadas fotografias antes e após a instrumentação e realizada uma análise computadorizada por meio de superposição das imagens. Os dados obtidos foram tratados estatisticamente com teste T de comparação de médias, havendo diferença estatisticamente significante (p=0,000, t=-25,383). De acordo com os resultados obtidos, concluiu-se que a instrumentação prévia dos canais radiculares com as limas Pathfile (Dentsply®/Maillefer) pode contribuir consideravelmente na redução da possibilidade de desvio no terço apical de canais radiculares curvos.

This study has aimed at verifying if the use of PathFile files minimizes the possibility of apical deviation during endodontic treatment with Protaper files in resin blocks with simulated canals. Digital photographs were taken before and after instrumentation and a computerized analysis through overlapping images. Data were statistically analyzed with t-test for comparison of means, and demonstrated a statistically significant difference (p = 0.000, t = -25.383). According to the results of this research, the authors concluded that previous instrumentation with PathFile (Dentsply©/Maillefer) system can contribute to a great reduction of transportation possibility on the apical third of curved root canals

Avaliação ex vivo da precisão de um localizador apical antes e após o pré-alargamento das paredes dos canais sob a influência de diferentes substâncias irrigadoras / Evaluation ex vivo precision of an apex locator before and after pre-flaring of the root canals under the influence of different irrigants

O objetivo desse trabalho foi avaliar, ex vivo, a influência do peróxido de hidrogênio (H 2 O 2 ) a 3,0% e do hipoclorito de sódio (NaOCl) a 2,5% e 5,25% na precisão das medidas obtidas por um localizador apical eletrônico antes e após o pré-alargamento. Foram utilizadas 25 raízes mesiais de primeiros molares inferiores, totalizando 50 canais radiculares, que tiveram as coroas cortadas na junção amelocementária. A medida real de cada canal foi realizada e, em seguida, as amostras foram incluídas em uma mistura de alginato, usada como meio condutor, onde foram realizadas as medições eletrônicas com o localizador apical auxiliadas com o uso das três soluções irrigadoras antes e após o desgaste do terço médio e cervical dos canais com brocas Gates-Glidden. As medidas obtidas pelo método eletrônico foram então comparadas com a medida real dos canais. Os resultados obtidos foram tabulados e submetidos ao teste estatístico t de Student. Os resultados revelaram que não houve significância estatística (p>0,05) entre as leituras obtidas antes e após o desgaste dos terços cervical e médio dos canais com uso de NaOCl 2,5 e 5,25%, com resultados demonstrando, em média, leituras mais próximas do comprimento real do canal no grupo sem pré-alargamento. Porém, observamos diferença estatística com uso de H 2 O 2 (p<0,05) entre as leituras obtidas tanto antes quanto após o desgaste dos dois terços iniciais do canal. Desta forma, conclui-se que o preparo médio-cervical com brocas Gates Glidden não foi capaz de interferir significativamente na precisão do localizador apical testado

The aim of this paper was to evaluate the influence of 3% hydrogen peroxide (H 2 O 2 ) and 2.5% and 5.25% sodium hypochlorite (NaOCl) measured by a root apex locator before and after the pre-flaring of the root canal. The mesial root of twenty five mandibular first molars, total of 50 root canals, was tested with the crown cut off from the enamel-cementum junction. The real measure of each root was defined and after that the samples were stored in a mix of alginate, used as a conductor. The measures were done with a root apex locator using three different irrigation solutions before and after the instrumentation of the medium and cervical parts of the roots by means of Gates-Glidden drills. The measures obtained by the electronic method were compared to the real length of each root canal. These data were evaluated by means of the student t test for statistical analysis that demonstrate no statistical differences between the measures before and after the pre-flaring using 2.5% or 5.25% sodium hypochlorite (p>0.05). The results showed measures closer to the actual root canal length in the group without the pre-flaring, however statistical significance was observed with 3% hydrogen peroxide between the measures done before and after the root canal pre-flaring (p<0.05). Thus, we concluded that the medium and cervical preparation with Gates-Glidden drills was not able to interfere in the root apex locator precision

In vitro genotoxicity and cytotoxicity in murine fibroblasts exposed to EDTA, NaOCl, MTAD and citric acid

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

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

A barodontalgia em voo e o diagnóstico diferencial de dor odontogênica: relato de caso / In flight barodontalgia and the differential diagnosis of odontogenic pain: a case report

Introdução: A barodontalgia é uma condição aguda que ocorre pela diferença de pressão atmosférica e que afeta a saúde e o bem-estar dos pilotos durante o voo. Os pilotos militares estão mais suscetíveis às diferenças de pressão em razão das manobras rápidas e situações extremas que enfrentam ou por não haver cabine pressurizada na aeronave. Tal ocorrência pode levar a vertigem, incapacitação do profissional e finalização prematura do voo. Sua origem pode estar no dente, relacionada a alguma patologia pré-existente ou não, e ainda em outras estruturas da face, principalmente no seio maxilar. Dos casos relatados na literatura, 70% decorreram de pulpite relacionada a restaurações profundas e a maior parte (81%) ocorreu na decolagem da aeronave. Objetivo: Apresentar um caso clínico de um piloto de T-29 da Força Aérea Brasileira, atendido na Odontoclínica de Aeronáutica Santos-Dumont, imediatamente após o pouso. Relato de caso: A anamnese apontou a diferença de pressão como fator desencadeador da dor dentária aguda. Após o diagnóstico de necrose pulpar, o dente foi submetido ao tratamento endodôntico em sessão única, pelo uso de sistema rotatório Protaper Universal® e obturação com técnica termoplastificada Híbrida de Tagger. Na consulta de reavaliação, o paciente não relatou qualquer outro episódio de dor dentária em voo. Conclusão: Torna-se evidente a relevância do conhecimento desta condição por cirurgiões-dentistas civis e militares, para a correta condução do diagnóstico e do tratamento de aeronavegantes.

Introduction: The barodontalgia is an acute condition due to the air pressure difference that affects the health and the well being of pilots during flight. Military pilots are more susceptible to pressure differences due to quick maneuvering, the extreme situations in flight, or due the lack of pressure into aircraft cabin. Such occurrence can lead to dizziness and premature end of the flight. Its origin may be in the tooth, related to some pre-existing condition or not, and also in other structures of the face, especially in the maxillary sinus. Of the cases reported, 70% came from pulpitis related to deep restorations, and most cases (81%) appeared in the aircraft taking off. Aim: To report a clinical case of a T-29 Brazilian Air Force pilot, who came to Santos-Dumont Air Force Dental Clinic, immediately after landing. The patient interview pointed out barodontalgia as a cause of his acute toothache. After the diagnosis of necrotic pulp, the tooth was endodontically treated in single session by using the Protaper Universal rotary system, and filling with Hybrid Tagger thermoplasticized technique. In the query of reevaluation, the patient reported no further episodes of dental pain in flight. Conclusion: It is evident the relevance of knowledge of this condition by military and civilian dentists, to conduct proper diagnosis and treatment of airmen.

Antimicrobial activity of sodium hypochlorite, chlorhexidine and MTAD® against Enterococcus faecalis biofilm on human dentin matrix in vitro

Objective: This study evaluated the antimicrobial efficacy of 2.5% and 5.25% NaOCl, 2% gel and liquid CHX and MTAD® against Enterococcus faecalis biofilms on human dentin. Material and methods: E. faecalis biofilms grown on dentin matrix of 216 root sections were submerged in test irrigants for 1, 5, 15 and 30 minutes. The antimicrobial activity of the test irrigants were assessed through CFU counts. Biofilm formation over the dentin surface was ensured by SEM analysis.Results: Results showed no statistic difference among CHX gel, 2.5% and 5.25% NaOCl. However, the CHX liquid and MTAD were less effective than 2.5% and 5.25% NaOCl. Only CHX liquid and MTAD had differences in its efficacy depending on the time.Conclusion: The most effective irrigants in eliminating E. faecalis biofilms were 2.5% and 5.25% NaOCl and 2% CHX gel, at all the tested time intervals, in comparison to CHX liquid and MTAD.

Effectiveness of an electronic apex locator used after preflaring of cervical and middle third

Introduction: The electronic method has been studied and improved aiming to add precision, speed and reliability of the measurement technique to determine the exact location of the working length. Currently, the root canal preparation recommends prior to determine the tooth length and consequent perform instrumentation of the apical portion, a previous preflaring of the cervical and middle thirds in various techniques. This procedure may provide a reduction in system impedance, leading to read errors by the apex locators. Objective: Investigate the influence of preflaring of the cervical and middle thirds on the accuracy of measuring the working length by apex locators. Material and methods: Twenty-five mesial roots of molars were used and had their crowns cut at the cemento-enamel junction. The actual measure of each root canal was performed and then the samples were embedded into a mixture of alginate, used as a conducting medium, where electronic measurements were taken with apex locator before and after preflaring of the canals with Gates-Glidden drills in descending order (#4, #3, #2). Measurements obtained by electronic method were then compared with the actual measurement of the root canal. The results were tabulated and submitted to the Student t test. Results: The results show that there was no statistical significance (p<0.05) between the readings before and after preflaring. Readings closer to the foraminal ending occurred in the group after preflaring with Gates Glidden. Conclusion: It was concluded that preflaring with Gates Glidden drills were not able to influence significantly the accuracy of apex locator in determining the exact working length.

A remodelação óssea de extensa lesão periapical apósuso de PRP e hidróxido de cálcio - relato de caso clínico / The remodeling of extensive periapical lesion after use of PRP and calcium hydroxide- case report

Durante o preparo do canal radicular, em algunscasos, se faz necessário o uso de medicação intracanal(MIC) com o objetivo de continuar asanificação do sistema de canais radiculares.Dentre o arsenal de medicamentos do endodontista,encontra-se o PRP (paramonoclorofenol2%, Rinossoro e polietilenoglicol), umacombinação de antissépticos que pode, ainda,ser associada ao hidróxido de cálcio, por suaspropriedades antimicrobianas e capacidade deindução da reparação tecidual. Este trabalhoteve por objetivo apresentar um caso clínicoda paciente F.G.M., 19 anos, leucoderma, quecompareceu à Odontoclínica de AeronáuticaSantos-Dumont, queixando-se de dor intensanos dentes anteriores. Ao exame clínico-radiográficofoi observado edema no palato, percussãovertical positiva e extensa lesão periapical doincisivo lateral superior direito. Após anestesia eisolamento absoluto, procedeu-se acesso, penetraçãodesinfetante, preparo químico-mecânicoe aplicação de pasta de PRP e hidróxido de cálcio,como MIC. Foram realizadas trocas mensaisdesta MIC por seis meses, até que se observassea regressão da lesão. A observação clínica e radiográficademonstrou que a associação dessesmedicamentos parece induzir boa resposta tecidual,culminando com a remodelação óssea dostecidos periapicais.

During root canal preparation, in some cases,it is necessary the use of intracanal medication(ICM) in order to continue the sanitation of theroot canal system. Among the variety of endodonticmaterials, there is PRP (paramonochlorophenol2%, Rinossoro and polyethylene glycol),a combination of antiseptics, which can also beassociated with calcium hydroxide because ofits antimicrobial properties and induction of tissuerepair ability. This study aimed to present aclinical case of FGM patient, 19 years old, Caucasian,who attended the Santos-Dumont AirForce Dental Clinic, reporting intense pain in the maxillary anterior teeth. After physical and radiographicexamination, an edema was observed onthe palate region, presenting positive vertical percussionand an extensive periapical lesion of upperright lateral incisor. After anesthesia and rubberdam isolation were carried out the access, chemical-mechanical preparation and application of PRPpaste and calcium hydroxide as MIC. Exchangesof MIC were conducted on a monthly basis for sixmonths until was observed the regression of thelesion. The clinical and radiographic observationshowed that the combination of these drugs seemto induce good tissue response, culminating in therepair of periapical tissues.

In vitro genotoxicity and cytotoxicity in murine fibroblasts exposed to EDTA, NaOCl, MTAD and citric acid.

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

Clinical management of a complicated crown-root fracture: a case report.

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

Efficacy of five rotary systems versus manual instrumentation during endodontic retreatment.

The purpose of this study was to evaluate the efficiency of ProFile, GT, ProTaper, Race and K3 rotary instruments compared with hand K-files for removal of gutta-percha during retreatment. Sixty mandibular premolars were instrumented with GT rotary files and filled by thermomechanical compaction of gutta-percha and AH Plus sealer. The teeth are randomly divided into 6 groups of 10 specimens each. The roots were split longitudinally, digital images were created using a flatbed scanner, and the areas with remaining filling material were demarcated using Image Tool 1.21 software. The results indicate that GT left significantly less (p<0.05) remaining filling material (1.18 ± 1.47) than hand (3.70 ± 3.16) and Hero instruments (2.99 ± 2.58). There was no statistically significant difference (p<0.05) among the others techniques: ProFile (1.99 ± 2.66), ProTaper (2.00 ± 1.99) and K3 (2.71 ± 2.87) when compared with GT. In conclusion, GT, ProFile, ProTaper and K3 were more effective in removing gutta-percha than manual and Hero instruments.

Clinical management of a complicated crown-root fracture: a case report

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

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

Efficacy of five rotary systems versus manual instrumentation during endodontic retreatment

The purpose of this study was to evaluate the efficiency of ProFile, GT, ProTaper, Race and K3 rotary instruments compared with hand K-files for removal of gutta-percha during retreatment. Sixty mandibular premolars were instrumented with GT rotary files and filled by thermomechanical compaction of gutta-percha and AH Plus sealer. The teeth are randomly divided into 6 groups of 10 specimens each. The roots were split longitudinally, digital images were created using a flatbed scanner, and the areas with remaining filling material were demarcated using Image Tool 1.21 software. The results indicate that GT left significantly less (p<0.05) remaining filling material (1.18 ± 1.47) than hand (3.70 ± 3.16) and Hero instruments (2.99 ± 2.58). There was no statistically significant difference (p<0.05) among the others techniques: ProFile (1.99 ± 2.66), ProTaper (2.00 ± 1.99) and K3 (2.71 ± 2.87) when compared with GT. In conclusion, GT, ProFile, ProTaper and K3 were more effective in removing gutta-percha than manual and Hero instruments.

O propósito deste estudo foi avaliar a eficiência dos instrumentos rotatórios ProFile, GT, ProTaper, Race e K3 comparados com limas K para a remoção do material obturador durante o retratamento. Sessenta pré-molares inferiores foram instrumentados com o sistema rotatório GT e obturados usando a técnica de compactação termomecânica de guta-percha com cimento AH Plus. Os dentes foram divididos aleatoriamente em seis grupos de dez espécimes cada. As raízes foram seccionadas longitudinalmente, imagens digitais foram criadas através de um scanner, e as áreas de remanescentes de material foram medidas usando o programa Image Tool 1.21. Os resultados indicaram que o GT deixou significantemente menos material remanescente (1,18 ± 1,47) do que os instrumentos manuais (3,70 ± 3,16) e os instrumentos Hero (2,99 ± 2,58) (p<0,05). Não houve diferença estatisticamente significante entre as outras técnicas ProFile (1,99 ± 2,66), ProTaper (2,00 ± 1,99) e K3 (2,71 ± 2,87) quando comparadas com o GT. Como conclusão, GT, ProFile, ProTaper e K3 foram revelados como mais efetivos em remover a guta-percha do que os instrumentos manuais e os instrumentos Hero.

Metodologias aplicadas para análise da capacidade de selamento dos materiais retrobturadores: revisão da literatura / Methodologies for analysis for the sealing ability of the root-end filling materials: literature review

O objetivo deste estudo consistiu em comparar, por meio de revisão da literatura, as diversas metodologias utilizadas para análise da capacidade de selamento dos materiais retrobturadores. Assim como, verificar quais destes materiais retrobturadores são capazes de promover melhor selamento apical, prevenindo a percolação e o consequente insucesso da terapia endodôntica. Com base nos resultados demonstrados pela literatura, pode-se chegar às seguintes considerações: a infiltração por glicose e a infiltração bacteriana foram as metodologias que melhor avaliaram a capacidade de selamento apical. Entretanto, serão necessários diversos estudos para a total comprovação da infiltração por glicose. O MTA foi o material retrobturador com melhor capacidade de selamento apical, nas diversas metodologias aplicadas.

The objective of this study was to compare, by reviewing the literature, the various methodologies used to analyze the sealing ability of the root-end fillings materials. As well as, to verify which of these root-end fillings materials are able to promote better apical sealing, preventing percolation and the consequent failure of endodontic therapy. Based on the results demonstrated by the literature, one can come to these following considerations: glucose leakage and bacterial leakage were the methodologies that best evaluated the apical sealing ability. However, various studies will be needed for total attesting the infiltration by glucose. MTA as a root-end filling material provided better apical sealing ability, in the various methodologies.

Tratamento endodôntico com laserterapia de lesão cística de grande volume na mandíbula - relato de caso / Endodontic treatment with laser therapy of large cystic lesion on the mandible - case report

Introdução e objetivo: Este trabalho teve como objetivo mostrar a possibilidade de tratamento não-cirúrgico de grandes cistos. Relato de caso: Realizou-se tratamento endodôntico de lesão perirradicular com aproximadamente 4,5 cm de diâmetro máximo, envolvendo as raízes dos dentes 36 e 37. Indicou-se tratamento de canal dos dentes antes do procedimento cirúrgico da lesão. Observou-se melhora clínica em 20 dias do início do tratamento endodôntico, com diminuição do edema e regressão cística. Optou-se por consultas de manipulação dos canais, colocação de pasta de hidróxido de cálcio e laserterapia. Após seis meses do início do tratamento verificou-se regressão clínica da lesão; procedeu-se à obturação endodôntica dos dentes e fez-se controle clínico radiográfico de 1 e 2 anos. Observaram-se desaparecimento do cisto e consequente reparação óssea. Conclusão: Com a utilização dos avanços tecnológicos, como microscópios e laserterapia, atualmente é possível, em casos de lesão perirradicular em que se recomendava cirurgia, efetuar tratamento não-cirúrgico com sucesso.

Introduction and objective: This study aimed to show the possibility of non-surgical treatment of large cysts. Case report: Endodontic treatment of periradicular lesion with approximately 4.5 cm in maximum diameter regarding the roots of teeth 36 and 37 was performed. Root canal treatment of teeth before the lesion surgical procedure was indicated. After twenty days from the endodontic treatment beginning, an improvement in the clinical condition was observed, with reduction of edema and cystic regression. Thus, the option was for sessions of canal manipulation, placement of calcium hydroxide paste and laser therapy. After six months from the treatment beginning, clinical regression of the lesion was observed; endodontic obturation of the teeth was performed, and clinical radiographic control was carried out for 1 and 2 years. Disappearance of cyst was observed and consequent bone repair. Conclusion: By using technological advances, such as microscopes and laser therapy, nowadays it becomes possible to perform successful non-surgical treatment in cases of periradicular lesion, to which surgery used to be the regular recommendation.