ABSTRACT
Abstract This study evaluated a new method of adhesive system application on the bond strength between fiber post and root dentin using two adhesive systems. The canals of sixty bovine incisors were prepared and obturated. The roots were divided into six groups (n=10) according to the adhesive system (Clearfil SE - CSE and Single Bond Universal - SBU) and the application strategy (microbrush - MB; rotary brush - RB; and ultrasonic tip - US). The glass fiber posts were cemented with resin cement (RelyX ARC). The roots were sectioned perpendicularly to their long axis, and three slices per root were obtained. Previously to the push-out test, confocal laser scanning microscopy (CLSM) was performed to illustrate the interfacial adaptation of the cement to the root canal walls. Failure patterns were analyzed with 40x magnification. Shapiro-Wilk indicated a normal distribution of the data. The bond strength values were compared using one-way ANOVA and Tukey's tests. Student's T test analyzed the differences between the adhesive systems within each third and protocol. A significance level of 5% was used. CSE with RB showed higher mean bond strength values compared to MB (conventional technique) (P < 0.05). US application resulted in intermediate bond strength values for CSE (P > 0.05). The application of SBU using RB generated higher mean bond strength values compared to MB and US (P < 0.05). Adhesive failures were predominant (65.5%). CSE and SBU application with the new rotary brush improved the bond strength of fiber posts to root dentin compared to the conventional strategy.
Resumo Este estudo avaliou o efeito de um novo método para aplicação do sistema adesivo na resistência de união entre pino de fibra e dentina radicular usando dois sistemas adesivos. Os canais de sessenta incisivos bovinos foram preparados e obturados. As raízes foram divididas em seis grupos (n=10) de acordo com o sistema adesivo (Clearfil SE - CSE e Single Bond Universal - SBU) e com a estratégia de aplicação (microbrush - MB, escova rotatória - RB e inserto ultrassônico - US). Os pinos de fibra foram cimentados utilizando cimento resinoso (RelyX ARC). As raízes foram seccionadas perpendicularmente ao seu longo eixo e três fatias foram obtidas. Previamente ao teste de push-out, foi realizada microscopia de varredura confocal a laser para ilustrar a adaptação interfacial do cimento às paredes do canal radicular. Os padrões de falha foram analisados com magnificação de 40x. O teste de Shapiro-Wilk indicou distribuição normal dos dados. Os valores de resistência de união foram comparados usando o teste ANOVA de uma via e post hoc de Tukey. As diferenças entre os sistemas adesivos em cada terço e de acordo com cada protocolo foram analisadas pelo teste T de Student. O nível de significância foi de 5%. CSE aplicado com RB apresentou maiores valores médios de resistência de união do que quando aplicado com MB (técnica convencional) (P<0,05). Aplicação com US apresentou valores intermediários de resistência de união para o CSE (P>0,05). A aplicação do SBU utilizando RB gerou maiores valores médios de resistência de união comparados com MB e US (P<0,05). Falhas adesivas foram predominantes (65,5%). A aplicação do CSE e SBU com a nova escova rotatória melhorou a resistência de união dos pinos de fibra à dentina radicular comparados com a estratégia convencional.
ABSTRACT
Abstract Acute periradicular abscess is a condition characterized by the formation and propagation of pus in the periapical tissues and generally associated with debilitating pain. Objective: The aim of this study was to compare the overall analgesic effectiveness of two combinations of opioid and non-opioid analgesics for acute periradicular abscess. Material and Methods: This study included 26 patients who sought emergency care in a Brazilian dental school. The patients were randomly divided into two groups: Co/Ac - oral prescription of codeine (30 mg) plus acetaminophen (500 mg), every 4 h, for 3 days or Tr/Ac - oral prescription of tramadol hydrochloride (37.5 mg) plus acetaminophen (500 mg) on the same schedule. Two factors were evaluated: (1) pain scores recorded by the patients in a pain diary 6, 12, 24, 48, and 72 h after treatment, using the Visual Analogue Scale; and (2) the occurrence of adverse effects. Results: In both groups, there was a reduction in pain scores over time. For the Co/Ac group, there was a significant reduction in the scores 12, 24, 48, and 72 hours after treatment (P<0.05). In the Tr/Ac group, the scores significantly decreased over time from time point 6 h (P<0.05). Comparing the pain at each time point, the groups were not significantly different (P>0.05), i.e., both treatments were effective in controlling pain caused by APA; however, the combination of Tr/Ac caused more adverse reactions as two patients had to stop using the medication. Conclusion: This study suggests that, considering both analgesic efficacy and safety, the combination of codeine and acetaminophen is more effective to control moderate to severe pain from acute periradicular abscesses.
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Young Adult , Periapical Abscess/surgery , Tramadol/therapeutic use , Codeine/therapeutic use , Analgesics, Non-Narcotic/therapeutic use , Acute Pain/drug therapy , Analgesics, Opioid/therapeutic use , Acetaminophen/therapeutic use , Pain, Postoperative/drug therapy , Time Factors , Pain Measurement , Double-Blind Method , Acute Disease , Reproducibility of Results , Treatment Outcome , Drug Therapy, Combination , Analgesia/methodsABSTRACT
Objectives The aim of this study was to evaluate the volume of remaining filling material after passive ultrasonic irrigation (PUI) of sodium hypochlorite (NaOCl) and orange oil in mesial canals of mandibular molars, with and without isthmus. Material and Methods Thirty mesial roots of mandibular molars were divided according to the presence or absence of isthmus. Canals were prepared and filled (Micro-CT #1). Filling was removed using rotary instruments, and specimens were sub-divided into three groups according to the irrigation procedures: Conventional – conventional irrigation with NaOCl, PUI/NaOCl – PUI of NaOCl (three activations, 20 seconds each), and PUI/orange oil – PUI of orange oil (Micro-CT#2). Specimens were enlarged using the X2 and X3 ProTaper Next instruments and submitted to the same irrigation protocols (Micro-CT #3). Results No differences were found between the experimental groups in each stage of assessment (P>0.05). The volume of residual filling material was similar to that in Micro-CT #2 and Micro-CT #3, but lower than that observed in Micro-CT #1 (P<0.05). When groups were pooled according to the presence or absence of an isthmus, volume of residual filling material was higher in specimens presenting isthmus (P<0.05). Conclusions PUI of NaOCl or orange oil did not improve filling removal. Isthmus consists in an anatomical obstacle that impairs the removal of filling material.
Subject(s)
Humans , Root Canal Filling Materials , Root Canal Irrigants/chemistry , Sodium Hypochlorite/chemistry , Ultrasonic Therapy/methods , Plant Oils/chemistry , Root Canal Preparation/methods , Time Factors , Tooth Root/anatomy & histology , Ultrasonic Therapy/instrumentation , Reproducibility of Results , Analysis of Variance , Root Canal Preparation/instrumentation , Retreatment , X-Ray Microtomography , Therapeutic Irrigation/instrumentation , Therapeutic Irrigation/methods , Mandible , Molar/anatomy & histologyABSTRACT
Abstract This study aimed to compare apical transportation, centering ratio, and working time during root canal preparation with Wizard Navigator (WN), WaveOne (WO), or ProTaper Universal (PT) and to describe deformation and fracture of these instruments. Thirty-six mesiobuccal roots from maxillary molars were micro-computed tomography (micro-CT) scanned and then sorted into three groups (n = 12): Wizard Navigator (WN), WaveOne (WO), and ProTaper Universal (PT). The root canals were prepared using WN, WO, or PT; the time of each canal preparation was timed; and the specimens were micro-CT re-scanned. The instruments were submitted to scanning electron microscopy (SEM) before and after their use. The data on canal transportation at 1, 2, 3, 4 and 5 mm and preparation time were analyzed by the Kruskal-Wallis test, followed by the Mann-Whitney U test. The centering ratio was analyzed by ANOVA, followed by Tukey's test. Both instrument deformation and fracture were described. Apical transportation was similar among groups at 1, 2, 3 and 4 mm. The WO group showed higher canal transportation at 5mm than the other groups (p = 0.03). There was no significant difference in centering ratio among the groups. Preparation time in the WO group was significantly lower than in the other groups (p = 0.004). Small differences were observed in the surface area of all instruments. The WN, WO, and PT groups had a similar centering ratio without procedural errors or significant structural changes. At 5 mm from the apex, the WO group showed the largest canal transportation toward the furcation and root canal preparation was faster than in the WN and PT groups.
Subject(s)
Humans , Root Canal Preparation/instrumentation , Dental Instruments , Dental Pulp Cavity/anatomy & histology , Time Factors , Titanium/chemistry , Microscopy, Electron, Scanning , Reproducibility of Results , Analysis of Variance , Statistics, Nonparametric , Root Canal Preparation/methods , Dental Pulp Cavity/diagnostic imaging , Equipment Design , X-Ray Microtomography , Molar/anatomy & histology , Nickel/chemistryABSTRACT
The aim of this study was to quantify the residual filling material after filling removal, re-preparation with rotary or reciprocating files and passive ultrasonic irrigation (PUI). Twenty maxillary molars were prepared using ProTaper instruments up to F1. The teeth were filled with AH Plus and ProTaper gutta-percha points using the single-cone technique. Thereafter, the specimens were scanned using a micro-computed tomography system (Micro-CT #1). Then, the root canal filling was removed using ProTaper Retreatment files, and a new scan was performed (Micro-CT #2). The specimens were divided into two groups according to the instrument used for re-preparation: ProTaper rotary or WaveOne reciprocating files (Micro-CT #3). Finally, PUI was performed, and a new micro-CT scan was performed (Micro-CT #4). Intragroup and intergroup analyses were performed using Friedman and Dunn's post hoc test and the Kruskal-Wallis and Dunn post hoc tests, respectively. Palatal canal presented the highest volume of residual filling material in all stages of endodontic retreatment (p<0.05). The main reduction of filling volume was achieved after using ProTaper Retreament (p<0.05). The amount of remaining filling material after using ProTaper Retreatment was similar to that achieved with rotary and reciprocating files and after PUI (p>0.05). Rotary and reciprocating files achieved similar removal of the root canal filling (p>0.05). The greatest reduction in filling material was achieved after using ProTaper Retreatment files. Rotary and reciprocating instruments and PUI did not improve the removal of root canal filling materials.
Resumo O objetivo dente estudo foi quantificar o material obturador residual após remoção da obturação, repreparo do canal com instrumentos de rotação contínua e reciprocantes e após irrigação ultrassônica passiva (IUP). Vinte molares superiores foram preparados usando instrumentos ProTaper sequencialmente até F1. Os dentes foram obturados com AH Plus e cones de guta percha ProTaper utilizando a técnica de cone único. Em seguida, os espécimes foram submetidos à microtomografia computadorizada (Micro-CT #1). Então, o material obturador foi removido utilizando instrumentos ProTaper Retratamento e novo escaneamento foi realizado (Micro-CT #2). Os espécimes foram divididos em dois grupos de acordo com o instrumento usado para o repreparo: de rotação contínua (ProTaper) ou reciprocante (WaveOne) (Micro-CT #3). Finalmente, IUP foi realizada e nova micro-CT foi conduzida (Micro-CT #4). As análises intra-grupo e inter-grupos foram realizadas utilizando os testes de Friedman e de Dunn e o teste de Kruskal-Wallis e Dunn, respectivamente. O canal palatino apresentou o maior volume de material obturador remanescente em todos os estágios do tratamento endodôntico (p<0,05). A maior redução do volume da obturação foi obtida após usar os instrumentos ProTaper Retratamento (p<0,05). A quantidade de material obturador remanescente após utilizar instrumentos ProTaper Retratamento foi similar àquela obtida após repreparo com instrumentos de rotação contínua e reciprocantes e após a IUP (p>0,05). Instrumentos de rotação contínua e reciprocantes proporcionaram similar remoção de material obturador (p>0,05). A maior redução do volume de material obturador foi obtida após utilizar os instrumentos ProTaper Retratamento. Instrumentos de rotação contínua e reciprocantes, assim como a IUP, não reduzíram o volume de material obturador remanescente.
Subject(s)
Humans , Root Canal Filling Materials , Root Canal Therapy/methods , X-Ray Microtomography/methods , ReoperationABSTRACT
AIM: The aim of this study was to evaluate the efficacy of different lengths of time of passive ultrasonic irrigation (PUI) in removing calcium hydroxide (CH) paste from root canal, using scanning electron microscopy and energy dispersive spectrometry (SEM/EDS). MATERIAL AND METHODS: Fifty-four human premolars were used. After coronal access, a size #15 K-file was used to obtain apical patency. Root canal preparation was performed using WaveOne 40.08 instruments. CH paste was placed into the root canal. Specimens were stored in a humid environment, and after seven days, they were divided into five groups (n=12) according to the irrigation protocols: Manual a size #40 K-file; PUI/1 1 min; PUI/2 2 min; PUI/3 3 min; and Control without CH paste. An elementary chemical microanalysis (SEM/EDS) was performed to quantify the presence of calcium on the dentinal walls. RESULTS: The percentage of calcium was higher in all experimental groups when compared to the control group (P < 0.05); but no differences among them were found (P > 0.05). CONCLUSION: The amount of calcium hydroxide paste on the dentinal walls was not dependent on length of time of ultrasonic activation. SEM/EDS analysis seems to be a reliable method to assess CH paste removal from the root canals.
ABSTRACT
Objetivos: Avaliar o manejo da dor em Endodontia por meio de dois estudos: Artigo 1 um ensaio clínico randomizado comparando a eficácia analgésica de duas associações de opioide e não opioide no controle da dor do Abscesso Dentoalveolar Agudo (ADA) em evolução; Artigo 2 uma revisão sistemática investigando a eficácia e segurança de terapia sistêmica para o tratamento da dor de origem endodôntica. Métodos: No Artigo 1, foram incluídos 24 pacientes que procuraram atendimento em serviço odontológico universitário do sul do Brasil. Após o atendimento de urgência, os pacientes foram alocados em dois grupos: Co/Pa prescrição da associação de codeína (30 mg) e paracetamol (500 mg), por via oral, a cada 4 h, por 3 dias; Tr/Pa - prescrição da associação de cloridrato de tramadol (37,5 mg) e paracetamol (500 mg), na mesma posologia do grupo anterior. Os escores de dor foram registrados pelo próprio paciente, nos tempos 6, 12, 24, 48 e 72 h após o atendimento, em diário específico de evolução da dor, por meio da Escala Analógica Visual (EAV). No Artigo 2, foi realizada uma revisão sistemática, por meio de buscas conduzidas nas bases de dados: MEDLINE, registro de ensaios clínicos da Cochrane Library, LILACS, SciELO, banco de teses/dissertações da Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) e referências dos artigos encontrados. Para serem incluídos, os artigos deveriam ser ensaios clínicos randomizados (ECRs), controlados e cegos, ou revisões sistemáticas com ou sem metanálise. Deveriam ter um dos braços de terapia constituído por analgésico ou anti-inflamatório, administrado por via oral, para controle da dor moderada a intensa, de origem endodôntica, mensurada por meio da Escala Analógica Visual, em adultos...
Aim: To evaluate the management of pain in Endodontics by two studies: Article 1 - a randomized clinical trial comparing the analgesic efficacy of two opioids and non-opioid associations in the pain control of Acute Dentoalveolar Abscess (ADA); Article 2 - a systematic review investigating the efficacy and safety of analgesic therapy in the management endodontic pain.Methodology: The Article 1 included 24 patients that looked for emergency treatment in a university dental clinic. These patients were divided into two groups: Co / Pa - prescription of codeine (30 mg) + acetaminophen (500 mg) oral, every 4 h, during 3 days; Tr / Ac - prescription of tramadol hydrochloride (37.5 mg) + acetaminophen (500 mg) as the previous group. Pain scores were recorded by the patient at 6, 12, 24, 48, and 72 h after treatment, in a pain diary, using the Visual Analogue Scale (VAS). The Article 2 was conducted in electronic databases, gray literature, and references of retrieved articles to analyze randomized clinical trials or systematic reviews with or without meta-analysis. One arms of the therapy should have comprised an anti-inflammatory or analgesic drugs, orally administered by adults, in order to control moderate to severe pain, measured by Visual Analogue Scale, cause by endodontic problems . Data were collected regarding the characteristics of the sample, scores of pretreatment pain, characteristics of compared groups, methodological quality aspects, additional analgesic use, and frequency of adverse events. Descriptive and inferential analyzes were performed. Results: In Article 1, in both groups there was a reduction in the pain scores over time...
Subject(s)
Analgesics, Non-Narcotic , Analgesics, Opioid , Pain , Periapical AbscessABSTRACT
AIM: The aims of this study were to assess the penetration of two endodontic sealers (salicylate and epoxy resin-based sealers) into dentinal tubules using CLSM; and to evaluate the bacterial leakage of roots filled with the same sealers associated with gutta-percha. MATERIAL AND METHODS: For sealer penetrability assessment, thirty bovine roots were instrumented and divided into three groups: AHP: EDTA + filling with AH Plus and gutta-percha (n=10), MTAF: EDTA + filling with MTA Fillapex and gutta-percha (n=10), control group: canals were not irrigated with EDTA and were filled with gutta-percha and AH Plus (n=5) or MTA Fillapex (n=5). Rhodamine B was added to the sealers in order to provide adequate fluorescence. The roots were transversely sectioned 3mm from the apex to enable CLSM analysis. Leakage was evaluated for turbidity of the broth in a split chamber model system for 30 days, using Enterococcus faecalis as a microbial marker. Thirty roots were instrumented and divided in four grupos: AHP: filling with AH Plus and gutta-percha (n=10); MTAF: filling with MTA Fillapex and gutta-percha (n=10); positive control: filling with gutta-percha without sealer (n = 5); negative control: sealing with cyanoacrylate to test the seal of the system (n = 5). RESULTS: The medians for dentinal tubule penetration were 6.8% (AHP) and 6.6% (MTAF) (P = 0.82). The average time for bacterial leakage was 8 days in both experimental groups (P = 0.79). CONCLUSION: MTA Fillapex and AH Plus presented similar behavior regarding dentinal tubule penetration and bacterial leakage.
Subject(s)
Humans , Male , Female , Therapeutics , Tooth Root , Dental Materials , Endodontics , MicroscopyABSTRACT
Objective: To evaluate the impact of the type of root canal preparation, intraradicular post and mechanical cycling on the fracture strength of roots. Material and Methods: eighty human single rooted teeth were divided into 8 groups according to the instruments used for root canal preparation (manual or rotary instruments), the type of intraradicular post (fiber posts- FRC and cast post and core- CPC) and the use of mechanical cycling (MC) as follows: Manual and FRC; Manual, FRC and MC; Manual and CPC; Manual, CPC and MC; Rotary and FRC; Rotary, FRC and MC; Rotary and CPC; Rotary, CPC and MC. The filling was performed by lateral compactation. All root canals were prepared for a post with a 10 mm length, using the custom #2 bur of the glass fiber post system. For mechanical cycling, the protocol was applied as follows: an angle of incidence of 45°, 37°C, 88 N, 4 Hz, 2 million pulses. All groups were submitted to fracture strength test in a 45° device with 1 mm/ min cross-head speed until failure occurred. Results: The 3-way ANOVA showed that the root canal preparation strategy (p<0.03) and post type (p<0.0001) affected the fracture strength results, while mechanical cycling (p=0.29) did not. Conclusion: The root canal preparation strategy only influenced the root fracture strength when restoring with a fiber post and mechanical cycling, so it does not seem to be an important factor in this scenario. .
Subject(s)
Humans , Post and Core Technique/instrumentation , Root Canal Preparation/instrumentation , Root Canal Preparation/methods , Tooth Fractures/etiology , Tooth Root/injuries , Analysis of Variance , Composite Resins/chemistry , Dental Instruments , Dental Stress Analysis , Dentin/anatomy & histology , Materials Testing , Reproducibility of Results , Stress, Mechanical , Surface Properties , Tooth Fractures/physiopathology , Tooth Root/anatomy & histologyABSTRACT
The purpose of this study was to assess the fracture resistance of extensively damaged teeth after two root canal preparation techniques (hand and rotary files) and after two filling techniques (active and passive compaction). Sixty-eight maxillary canines roots with an apical diameter equal to that of a #25 K-file were embedded in acrylic resin and the periodontal ligament was simulated by using a polyether impression material. The roots were randomly distributed into four groups (n=17): hand preparation and active compaction (HA), hand preparation and passive compaction (HP), rotary preparation and active compaction (RA), and rotary preparation and passive compaction (RP). All roots were restored with glass fiber post and metallic crown. The specimens were mechanically cycled (500,000 cycles, 45°, 37°C, 133 N, 2 Hz) and then subjected to a fracture resistance test. A single blinded examiner analyzed the external root surface and classified the failure pattern as favorable or unfavorable. The fracture resistance values ranged between 621.15 N (HP) and 785.71 N (HA). However, the Kruskal-Wallis test did not reveal differences in the fracture resistance values among the four groups (p =0.247). Under the tested conditions, root canal preparation and filling techniques had no influence on the fracture resistance of extensively damaged teeth restored with fiber post and metallic crown.
O objetivo deste estudo foi avaliar a resistência à fratura de dentes amplamente destruídos após duas técnicas de preparo (limas manual e rotatória) e após duas técnicas obturadoras (compactação ativa e passiva). Sessenta e oito raízes de caninos superiores com diâmetro apical igual a uma lima K #25 foram embutidas em resina acrílica e o ligamento periodontal foi simulado utilizando um material de moldagem à base de poliéter. As raízes foram distribuídas aleatoriamente em quatro grupos (n=17): preparo manual e compactação ativa (MA), preparo manual e compactação passiva (MP), preparo rotatório e compactação ativa (RA) e preparo rotatório e compactação passiva (RP). Todas as raízes foram restauradas com pino de fibra de vidro e coroa metálica. Os espécimes foram ciclados mecanicamente (500.000 ciclos, 45°, 37°C, 133 N, 2 Hz) e depois submetidos ao teste de resistência à fratura. Um único examinador cego analisou a superfície externa das raízes e classificou o padrão de falha em favorável ou desfavorável. Os valores de resistência à fratura variaram entre 621,15 N (MP) e 785,71 N (MA). Entretanto, o teste de Kruskal-Wallis não revelou diferença nos valores de resistência à fratura entre os quatro grupos (p=0,247). Diante das condições testadas, as técnicas de preparo e de obturação do canal radicular não influenciam na resistência à fratura de dentes amplamente destruídos restaurados com pino de fibra de vidro e coroa metálica.
Subject(s)
Humans , Root Canal Therapy , Tooth Fractures , Cuspid , MaxillaABSTRACT
The aims of this study were to evaluate the effect of root canal filling techniques on root fracture resistance and to analyze, by finite element analysis (FEA), the expansion of the endodontic sealer in two different root canal techniques. Thirty single-rooted human teeth were instrumented with rotary files to a standardized working length of 14 mm. The specimens were embedded in acrylic resin using plastic cylinders as molds, and allocated into 3 groups (n=10): G(lateral) - lateral condensation; G(single-cone) - single cone; G(tagger) - Tagger's hybrid technique. The root canals were prepared to a length of 11 mm with the #3 preparation bur of a tapered glass fiber-reinforced composite post system. All roots received glass fiber posts, which were adhesively cemented and a composite resin core was built. All groups were subjected to a fracture strength test (1 mm/min, 45°). Data were analyzed statistically by one-way ANOVA with a significance level of 5%. FEA was performed using two models: one simulated lateral condensation and Tagger's hybrid technique, and the other one simulated the single-cone technique. The second model was designed with an amount of gutta-percha two times smaller and a sealer layer two times thicker than the first model. The results were analyzed using von Mises stress criteria. One-way ANOVA indicated that the root canal filling technique affected the fracture strength (p=0.004). The G(lateral) and G(tagger) produced similar fracture strength values, while G(single-cone) showed the lowest values. The FEA showed that the single-cone model generated higher stress in the root canal walls. Sealer thickness seems to influence the fracture strength of restored endodontically treated teeth.
O objetivo deste estudo foi avaliar o efeito da técnica de obturação na resistência à fratura de raízes e analisar, por meio de análise de elementos finitos (AEF), a expansão do cimento endodôntico em duas diferentes técnicas de obturação. Trinta dentes humanos unirradiculares foram instrumentados com limas rotatórias, com um comprimento de trabalho padronizado (14 mm). Os espécimes foram embutidos em um cilindro plástico com resina acrílica, e distribuídos em 3 grupos (n=10): G(lateral) - condensação lateral; G(cone único) - cone único; G(tagger) - técnica híbrida de Tagger. Os canais radiculares foram preparados num comprimento de 11 mm com a broca de preparo do sistema de pinos de fibra reforçado por compósito. Todas as raízes receberam pinos de fibra de vidro, as quais foram adesivamente cimentadas, e a reconstrução do núcleo foi realizada com resina composta. Todos os grupos foram submetidos ao teste de resistência à fratura (1 mm/min, 45°). Os dados foram submetidos ao teste de análise de variância 1 fator. A AEF foi executada através de dois modelos: um simulou a técnica da condensação lateral e a técnica híbrida de Tagger, e o outro simulou a técnica do cone único. O último foi desenhado com a guta-percha duas vezes menor e com a espessura de cimento duas vezes maior que o primeiro modelo. Os resultados foram analisados usando o critério de tensão Von Mises. A análise de variância a um fator indicou que a técnica de obturação afetou a resistência à fratura (p=0.004). G(lateral) e G(tagger) obtiveram similares valores de resistência à fratura, enquanto G(cone único) apresentou os menores valores. A AEF mostrou que o modelo do cone único gerou um aumento de tensão nas paredes do canal radicular. A espessura do cimento pareceu influenciar a resistência à fratura dos dentes tratados endodonticamente e restaurados.