Influência da reinstrumentação do degrau apical radicular após o posicionamento primário do cone principal de guta-percha noselamento apical

The aim of this study was to evaluate in vitro the apical leakage after the apical re-preparation and replacement of the principal gutta-percha point plus endodontic sealer (Sealer 26TM). Sixty extracted human canines were prepared by using a step back technique up to size 50 K type file apically. At each change of instrument the canals were irrigated with distilled water. After that step, the external surface roots were coated and subdivided into six groups with ten roots each: I – single gutta percha point technique; II – lateral condensation and III – hybrid technique. The IV, V and VI groups were similar to others groups but after to place the principal gutta percha point, it was removed, re-prepared up to size 60K file and in sequence replaced the principal gutta percha point and the root canal filling finished. The specimens were immersed in 2% Rhodamine BTM for 7 days at 37 oC. The apical leakage was measured by Image ToolsTM program. With Kruskal Wallis test statistical analysis showed that there was no significant difference between the techniques (p > 0.05).

Influência do cimento obturador e agente de irrigação final na infiltração marginal em situações de sobreobturações endodônticas

Objective: The objective of this paper was to verify if the final irrigation at 17% EDTA, separately or followed by chlorhexidine digluconate at 2% interferes on the apical marginal leakage in root canal overfilling, due to the use of two root canal filling materials (Sealer 26TM or SealapexTM). Methods: Forty lower incisors extracted, with a single root canal, were biomechanically prepared, at 2.0mm beyond the radicular apex, with ProTaper SystemTM, finishing it with the F3 instrument. Irrigation was accomplished with 1.0 mL NaOCl at 2.5% at each change of equipment caliper and, in the end, with 5.0 mL normal saline solution. After achieving this procedure, the foraminal channels was standardized with a file K 25 until its DO appears in the foraminal opening. From this moment, the teeth were subdivided into two groups of 20 specimens each, because of the final irrigation method used: I – irrigation with EDTA at 17% for 3min and II – identical protocol, thus, after EDTA aspiration at17%, it was again irrigated with chlorhexidine digluconate at 2%, also kept intra-canal for 3min. Each group was again sub-divided into two sub-groups (ten teeth each), according to the cement used (Sealer 26TM or SealapexTM), and filled by using a single gutta-percha F1 (ProTaperTM, Universal Filling), in such a manner that it goes 2.0 mm beyond the radicular apex. Soon after that, the teeth were immersed in Rhodamine BTM for 72h, vacuum and after the roots have been bucolingually grooved, the leakages marked were measured with program Image ToolTM. Results and Conclusions: The leakage magnitude was similar among themselves (p > 0.05), except for group Sealapex®, thus the final use with chlorhexidine reduced apical leakage (p < 0.05).

Resolução por retratamento não cirúrgico de dente com lesão periapical: relato de caso clínico

The development and maintenance of periapical lesion occurs as a result of bacterial infection of the root canal system. Faced with the failure of endodontic treatment, retreatment is the first option with great potential for success, when performed with proper disinfection of the root canal system. Case report: Patient aged 39 years needing dental care show at clinical examination moderate gingival bleeding in the region of tooth 22 and the presence of radiographic periapical bone rarefaction due to unsatisfactory endodontic treatment. It was indicated the endodontic retreatment. We performed procedures to remove the filling material, root canal preparation using manual and mechanical techniques and completion with the use of root canal medication based on calcium hydroxide. After root canal filling, clinical and radiographic success were demonstrated for the case. Conclusion: We conclude that the non-surgical retreatment with disinfection and proper use of medication to the base of calcium hydroxide promoted success after outcome monitoring for 2 years and 8 months (AU)

Capacidade de termoplastificação da guta-percha com diferentes conicidades

jObjective: The objective of this study was to evaluate the thermoplasticity of the gutta-percha cones used for root canal obturation: Dentsply convencional (Dentsply Ind. e Com., Petrópolis, RJ, Brazil), Dentsply 0.04, (Dentsply Ind. e Com., Petrópolis, RJ, Brazil), Antaeos 0.04 (VDW GmbH, Munich, Germany), ProTaper (Dentsply Ind. e Com., Petrópolis, RJ, Brazil) and Alfa 0.06 (VDW GmbH, Munich, Germany). Material and method: Specimens of each material (n = 10) were prepared after heating. After 24 hours were again heated to 70 °C and placed between two glass plates and subjected to a compression of 5 kg for 2 minutes. The scanned image of the groups before and after the compression was analyzed with the software Image Tool (UTHSCSA Image Tool for Windows version 3.0, San Antonio, TX, USA). The flow capacity of the different materials was determined by the difference between the initial and final area of each specimen. The results were submitted to ANOVA and Tukey test with significance level of 5%. Result: Among the material evaluated, the gutta-percha cones Alpha 0.06 and ProTaper presented more thermoplasticity than other groups (p < 0.05). The Dentsply gutta-percha presented thermoplasticity intermediate. The groups Dentsply 0.04 and 0.04 showed lower thermoplasticity after heating (p > 0.05). Conclusion: The gutta-percha present different property of thermoplasticity, which is important to selection of thermoplastic obturation techniques.

Effectiveness of gutta-percha and Resilon in filling lateral root canals using thermomechanical technique

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Análise físico-química do MTA e do cimento Portland associado a quatro diferentes radiopacificadores

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of Sealer Placement Technique on the Quality of Root Canal Filling by Lateral Compaction or Single Cone

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Replantation as treatment for extrusive luxation

In the treatment of extrusive luxation cases, it is important that the repositioning of extruded tooth in the socket is done as soon as possible. If this does not occur, periapical clot becomes organized and makes replantation difficult reposition. In this article the patient referred to the Clinics for dental trauma sustaining extrusive luxation of the maxillary right central incisor. The patient reported having suffered a bicycle accident 12 days before, which caused traumatic tooth injuries. The repositioning was attempted without success and an alternative form of treatment was necessary to solve the case. Intentional tooth replantation, which is the deliberate extraction of the tooth and its replantation, was indicated. This technique allows clot removal and correct repositioning of the extruded tooth. Care should be taken as endodontic treatment is required for the prevention of subsequent infection-related resorption. Intracanal dressing with calcium hydroxide was used for 30 days before final root filling. Splint, systemic antibiotics and avoidance of further damage to the root surface is also important. After 49 months, showed clinical and radiographic characteristics of normality and demonstrates the availability of this technique to adversity in trauma.

Fracture resistance of simulated immature teeth after different intra-radicular treatments

The aim of this study was to evaluate the fracture resistance of simulated immature teeth after different intra-radicular treatments. Crowns and roots of bovine incisors were cut transversally and removed to simulate immature teeth. Root canal preparation and flaring were performed using a bur in crown-apex and apex-crown direction. The samples were distributed into 5 groups (n=10): Positive control (PoC) - no root canal flaring or filling; Negative control (NeC) - teeth were sectioned and their root canals were flared; Direct anatomical glass fiber post (RaP) - #2 Reforpost main glass fiber post relined with composite resin; Double tapered conical glass fiber posts (ExP) - #3 Exacto glass fiber post; and #2 Reforpost main glass fiber + Reforpin accessory glass fiber posts (RrP). In RaP, ExP and RrP, 4.0-mm apical plugs were done with MTA Angelus. The specimens were embedded in polystyrene resin inside cylinders and the periodontal ligament was simulated with a polyether-based impression material. The specimens were submitted to compressive fracture strength test (0.5 mm/min at 135° relative to the long axis of the tooth) in a servo-hydraulic mechanical testing machine MTS 810. Data were subjected to one-way ANOVA and Dunnett's C or Tukey's tests (α=0.05). The control groups (PoC and NeC) showed lower fracture strength than the experimental groups. NeC presented the lowest resistance and ExP presented the highest resistance among the experimental groups. The flaring procedures produced a detrimental effect on the fracture resistance of the bovine teeth. Glass fiber intra-radicular posts increased significantly the fracture resistance of simulated immature teeth.

Citocompatibilidade, propriedades antibiofilme e físicas e cimentos endodônticos associados à amoxilina

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação da resposta tecidual e capacidade de mineralização de cimentos que contém compostos biocerâmicos, resinosos e com hidróxido de cálcio

Pós-graduação em Ciência Odontólogica - FOA

Root canal filling: fracture strength of fiber-reinforced composite-restored roots and finite element analysis

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.

Atividade antimicrobiana de cimentos endodônticos

The antimicrobial activity is a fundamental property of root-canal sealers due to persistence of residual microorganisms in the root canal system, even after the chemo-mechanical preparation and using of intracanal dressing. The aim of this study is to review the literature about the antimicrobial properties of some of the main root-canal sealers. Although there is controversy regarding this property, probably due to differences in the methodologies used in the studies, it was concluded that the sealers with the best antimicrobial activity were (in ascending order): Endofill, Ketac Endo, Sealapex, AH Plus, Endo CPM Sealer, Sealer 26 and Epiphany. Activ GP still needs scientific research to evaluate this property.

Tratamento tardio de traumatismo dentário anterior pela técnica de apicificação

Introdução: paciente do sexo masculino, 37 anos de idade. Após a anamnese, foi constatado que o dente 11 apresentava abertura coronária e presença de hidróxido de cálcio com histórico de trauma dentário nesse dente. Radiograficamente, o dente 11 apresentava formação radicular incompleta, paredes dentinárias finas e frágeis, com divergência foraminal associada a imagem radiolúcida periapical. Objetivo: relatar um caso clínico de apicificação, realizado com trocas de curativo de hidróxido de cálcio. Métodos: o tratamento de escolha foi a apicificação, a qual teve início na segunda sessão, após 15 dias, por meio de desbridamento químico-mecânico de todo o canal radicular, com limas tipo K e irrigação com uma solução de hipoclorito de sódio a 2,5%. Em seguida, pasta de hidróxido de cálcio (hidróxido de cálcio, iodofórmio e propilenoglicol) foi aplicada e trocada de 15 em 15 dias, durante 4 meses. O exame radiográfico foi novamente realizado e demonstrou o fechamento completo da abertura foraminal e regressão da radiolucência periapical. O canal radicular foi obturado utilizando-se um cone confeccionado a partir da união de três cones #60 e pela técnica de condensação lateral com Sealapex. Resultados: seis meses após a obturação, exames revelaram tecidos periapicais normais e ausência de sintomas. Conclusão: concluiu-se que o tratamento do traumatismo dentário associado à necrose do tecido pulpar e à lesão periapical, com trocas sucessivas de pasta de hidróxido de cálcio, foi adequado para se obter a regressão da lesão periapical, formação de barreira mineralizada e promoção de saúde ao paciente.

Terapia fotodinâmica na Endodontia: emprego de uma estratégia coadjuvante frente à infecção endodôntica

O tratamento endodôntico é de fundamental importância para abolir a infecção nos dentes com necrose pulpar. O sucesso desse tratamento depende: da eliminação eficiente da infecção no sistema de canais radiculares (SCR) e do correto selamento pela obturação dos canais radiculares. Devido à complexidade anatômica do SCR, certas áreas podem ser inacessíveis ao preparo biomecânico (PBM), portanto, o emprego de uma medicação intracanal potencializa a redução dos microrganismos (MO) e seus produtos tóxicos no SCR. Mesmo com o avanço técnico e científico da Endodontia, há MO que ainda sobrevivem ao PBM, sendo os principais responsáveis pela manutenção infecção endodôntica. Assim, novos tratamentos devem ser pesquisados. Com o advento dos aparelhos de laser e LED, surgiram alternativas de tratamentos na área da saúde, como a terapia fotodinâmica (TFD), que é um conjunto de procedimentos físicos, químicos e biológicos, que ocorrem após a administração de um agente fotossensibilizador (FS) ativado por meio de uma luz visível de comprimento de onda específico (laser ou LED) para destruir a célula-alvo, ou auxiliar no combate das infecções. Na Endodontia, foram demonstrados em estudos in vitro e in vivo que o emprego da TFD atua como um coadjuvante e potencializa a desinfecção do SCR, além de ser de fácil aplicação e não promover resistência microbiana. O objetivo da presente revisão é apresentar o estado atual da terapia fotodinâmica em Endodontia.