Carlos da Silveira Bueno

página 1 de 1, 1 / 1, LILACS, seleciona. para imprimir. Fotocópia. Texto completo. experimental, Documentos relacionados. Id: 509367. Autor: Barros, Pedro Paulo; Cunha, Rodrigo Sanches; Silva, Gustavo Henrique da; Cassu, Silvana Navarro; Bueno, Carlos Eduardo Silveira. ...

Objective The aim of this study was to compare the cyclic fatigue of heat-treated and non-treated instruments. Materials and Methods Twenty instruments with and without heat treatment from Bassi Logic were evaluated (n = 10). All instruments were subjected to dynamic cyclic fatigue through continuous rotations inside a stainless-steel tube (1.4-mm diameter, 9-mm curvature with 6-mm radius, and 90° angle) using a custom-made device, which performed 1 axial oscillation every 2 seconds with an amplitude of 3 mm, powered by a torque-controlled motor (Silver Reciproc, VDW, Germany), with speed adjusting to 950 rpm and torque to 4 N, according to manufacturer's guidance. The groups were compared using the Mann–Whitney test. Result The fracture time of the heat-treated instruments (97.20 ± 39.94 second and non-treated instruments (14.30 ± 6.78 seconds had statistical differences [p < 0.05]). Heat-treated instruments were 6.8 times more resistant to fatigue than non-treated instrumen...

This study aimed to evaluate the efficacy of 5 irrigation protocols in removing calcium hydroxide in simulated internal root resorption cavities. Eighteen extracted human teeth, upper anterior and uniradicular, were prepared up to size 50. The teeth were divided longitudinally, and internal root resorption cavities were made by acid demineralization using nitric acid. The same sample was submitted to the five irrigation protocols. The cavities and root canals were filled with Ultracal XS (Ultradent, South Jordan, UT, USA) and stored in an incubator at 37oC for one week. Afterward, the irrigation protocols were carried out: XP-endo Finisher (XPF; FKG, La Chaux-de-Fonds, Switzerland), passive ultrasonic irrigation (PUI), Easy Clean (Bassi/Easy Equipamentos Odontologicos, Belo Horizonte, Brazil) with reciprocating movement (ECR), Easy Clean with continuous rotation (ECC) and conventional irrigation with a syringe (CI). The solutions used, 2.5% NaOCl, and 17% EDTA, were warmed. The tota...

During the past few decades, the endodontic treatment has benefited from the development of new techniques and devices, which have improved the outcome and predictability. Important attributes such as the operating microscope and ultrasonics have found indispensable applications in a number of dental procedures in endodontics. Objective and case report: This study describes a case of endodontic retreatment of a maxillary first molar in which the second mesiobuccal canal could be located by extending the access to the mesial direction further than usual and by a closer inspection of the pulp chamber floor. Conclusion: The “microsonics concept” has enhanced the quality of endodontic treatment and retreatment, becoming increasingly more useful in applications such as localization of root canal orifices.

INTRODUCTION The aim of this study was to evaluate pain perception, pain medication intake, and sealer extrusion after single-visit root canal treatment of asymptomatic teeth, with or without foraminal enlargement. The correlation between sealer extrusion and pain was also investigated. METHODS One hundred and forty necrotic, single-rooted teeth were divided into two groups (n = 70): foraminal patency (FP), in which treatment was performed up to 1 mm short of the apex, and foraminal enlargement (FE), in which treatment was performed up to the apex. The canals were instrumented using WaveOne Gold files, irrigated with 2.5% sodium hypochlorite, and filled using the single-cone technique and AH-Plus sealer. A visual analog scale was used to record pain 24, 48, 72 hours, and 1 week postoperatively. The presence or absence of sealer extrusion was recorded. RESULTS Pain levels were significantly higher for FE than FP at 24 hours (p < 0.05), namely 0.3 ± 0.9 versus 0.1 ± 0.1; no difference was found at 48 hours, namely 0.1 ± 0.5 versus 0.0 ± 0.0 (p > 0.05). No pain was reported 72 hours or 1 week postoperatively in either group. Although all patients requiring pain medication at 24 hours were from the FE group, the difference between FE and FP was not statistically significant with respect to this variable (p > 0.05). Nevertheless, intake amount was significantly higher in FE than in FP at this time point (p < 0.05). Sealer extrusion occurred more frequently in FE than FP, namely 57.14 % versus 14.29% (p < 0.05). There was no association between pain and sealer extrusion (p > 0.05), or between pain and sex, age or tooth type (p > 0.05). CONCLUSION FE was related to higher pain levels 24 hours postoperatively, and to higher rates of filling material extrusion; however, there was no association between filling material extrusion and postoperative pain.

Objetivo: viabilizar a utilizacao de dentes deciduos artificiais com polpa e condutos radiculares em pesquisas “in vitro” com o uso do localizador apical Root ZX II. Metodo: foram selecionados 20 molares deciduos artificiais que apresentavam tres condutos radiculares e nao apresentavam trincas, fraturas ou defeitos de fabricacao. Foi feita abertura coronaria, acesso aos condutos, patencia foraminal e mensuracao dos canais radiculares por meio de metodo visual e eletronico. A mensuracao no metodo visual (G1- controle) foi realizada introduzindo a lima no ponto da cuspide de referencia ate a lima atingir o forame apical. No metodo eletronico (G2- experimental), os dentes foram inseridos em alginato e a lima inserida no canal radicular ate o localizador indicar o apice. As mensuracoes foram realizadas em triplicata. As medias das medidas em milimetros foram submetidas ao teste de correlacao de Pearson no programa Biostat 2.0 com valor de significância de 5%. Resultados: as medidas obse...

Introduction: The aim of this study was to evaluate the effectiveness of 2.5% sodium hypochlorite associated with 17% Ethylenediaminetetraacetic acid (NaOCl-EDTA), versus that of 1% peracetic acid (PA), in removing the smear layer, as assessed by scanning electron microscopy (SEM), and in exerting bactericidal action against Enterococcus faecalis ( E. faecalis ) , as assessed by the real-time polymerase chain reaction (real-time PCR). Methods and Materials: Fifty-five extracted mandibular single-rooted premolars were selected, and divided into two experimental groups (NaOCl-EDTA and PA; n =25) and one control group (0.9% saline; n =5). Pre- and post-instrumentation samples were collected and assessed for the presence of E. faecalis using real-time PCR. The teeth were instrumented using hand files and the ProTaper Universal system (hybrid technique) for a standardized time of 7 min. A total of 20 mL of NaOCl followed by 5 mL of EDTA were applied during instrumentation in the NaOCl-ED...

This study evaluated the ability of reciprocating glide path instruments to reach the full working length (RFWL). Thirty mesial roots of mandibular molars were matched into 2 groups (n = 15 teeth, 30 root canals), according to the system used for glide path: WaveOne Gold Glider (WOGG) and R-Pilot. The samples with fractured instruments or when it was not possible to RFWL were scanned using micro-computed tomography. Fractured instruments were also visualised through a scanning electron microscopy to verify the type of fracture. The parameters were compared statistically by Fisher's and chi-square tests (P < 0.05). No instrument fractures were observed in the R-pilot, while 2 fractures occurred in the WOGG group (P > 0.05). RFLW was achieved in 29 canals (96.66%) and 28 canals (93.33%) with R-pilot and WOGG instruments, respectively (P > 0.05). The instruments are able to RFWL in mesial canals of mandibular molars. WOGG showed two fractures while no R-Pilot instruments fractured.

ABSTRACTObjectives: The purpose of this study was to assess the in vitro antibacterial activity of four formulations of calcium hydroxide [Ca(OH)2] pastes against Enterococcus faecalis, Staphylococcus aureus, Pseudomonas aeruginosa and Streptococcus mutans. Methods: A broth dilution test was performed, and the lengths of time for different pastes to kill the microbial cells were recorded and statistically analyzed. The following medications were assessed: Group I – Ca(OH)2 + 2.0% chlorhexidine (CHX) gel; Group II – Ca(OH)2 + camphorated paramonochlorophenol (CMCP) and propylene glycol; Group III – Ca(OH)2 + propylene glycol; Group IV – Ca(OH)2 + saline. Results: The results showed that E. faecalis was the most resistant microorganism. Groups II and III eliminated all the microbial cells in 15 seconds. Group I took 45 seconds to eliminate E. faecalis. Conclusions: Under the conditions of this study, it was concluded that all the intracanal medications tested showed antibacterial acti...

The aim of this in vitro study was to identify the formation of dentinal defects on the external apical root surface of teeth instrumented at different working lengths by using WaveOne reciprocating files. Sixty human single-rooted mandibular premolars were divided into 3 groups (n = 20) according to the file used for instrumentation: WaveOne Small (WOS), premolars presenting mechanical resistance to the penetration of #10 K-file 1 mm short of the apical foramen; WaveOne Primary (WOP), this limit easily reached with #10 K-file; and WaveOne Large (WOL), this limit easily reached with #20 K-file or higher. A closed system and a muffle were created to allow alternating sessions of root canal instrumentation and image acquisition. The teeth were further divided according to 3 different working lengths: 1 mm short of the apical foramen, flush with the apical foramen, and 1 mm beyond the apical foramen. Micrographs of the external apical root surface of each specimen at baseline and after...

Glide path preparation has been recommended as a mandatory clinical step to ensure the safe usage of nickel-titanium (NiTi) rotary instruments. This study aimed to evaluate the effectiveness and fracture rate of 4 pathfinding NiTi rotary instruments in mechanically negotiating moderately curved molar canals. Moderately curved maxillary (n = 120) and mandibular (n = 120) molars were randomly distributed into 4 experimental groups (n = 60, 30 maxillary and 30 mandibular molars) according to the instrument used for glide path preparation: ScoutRace 10/.02 (FKG Dentaire, La Chaux-de-Fonds, Switzerland) (800 rpm and 1-Ncm torque), ProDesign 25/.01 (Easy Equipamentos Odontológicos, Belo Horizonte, MG, Brazil) (350 rpm and 1-Ncm torque), Mtwo 10/.04 (VDW, Munich, Germany) (280 rpm and 1.2 Ncm torque), or ProGlider 16/.02 (Dentsply Maillefer, Ballaigues, Switzerland) (300 rpm and 5-Ncm torque). The instrument fracture rate and the absolute and percentage frequencies of molars in which the p...

The aim of this study was to assess the effect of time and the ultrasonic activation of ethylenediaminetetraacetic acid (EDTA) in removing the smear layer of at root canal. A total of 60 bovine inferior incisors were transversely sectioned and instrumented; A smear layer was added in the root dentin surface. The specimen were then divided into six groups according to the following final irrigation protocols: Group (G) 1: conventional irrigation with sodium hypochlorite (NaOCl); G2: conventional irrigation with NaOCl + EDTA for 20 s; G3: conventional irrigation with NaOCl + EDTA for 60 s; G4: passive ultrasonic irrigation (PUI) with NaOCl; G5: PUI with NaOCl + PUI with EDTA for 20 s; G6: PUI + NaOCl and PUI with EDTA for 60 s. Samples were analyzed by scanning electron microscope (SEM) at ×500 increase. The images were measured by three blinded evaluators and classified in scores ranging from 1 to 5. The results were analyzed by the Pearson correlation test and the ANOVA nonparametric Kruskal-Wallis and Dunn's tests were used for the comparisons. Irrigated samples only with NaOCl (G1 and G4) had higher scores when compared with other groups. G5 and G6, irrigated with 17% EDTA and ultrasonic irrigation had lower scores. However, there was no statistically significant difference in G2 and G3, where there was no irrigation. It was concluded that irrigation with 17% EDTA for 20 s promoted the effective removal of smear layer, regardless of ultrasonic irrigation.

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 v...

This study evaluated the efficiency and effectiveness of three glass fiber post removal techniques. 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. 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. There was no significant difference in efficiency among the evaluated techniques.

The present study assessed the obturation removal and reinstrumentation working time of canals filled with Resilon/Real Seal in comparison with canals filled with gutta-percha/AH Plus. Thirty human extracted canines were instrumented. In group 1 (n = 15) root canals were filled with Resilon/Real Seal and in group 2 (n = 15) with gutta-percha/AH Plus sealer. The obturations were removed from both by using chloroform and irrigation with 2.5% NaOCl, and the canals were manually reinstrumented. The teeth were radiographically analyzed. Specimens without obturation material remnants visible in the radiographic examination were selected for analysis under scanning electron microscopy. The Resilon/Real Seal system was removed in greater quantities from the canal walls compared with the gutta-percha cones and the AH Plus cement. Time was not a significant factor. Under scanning electron microscopy analysis, the teeth presented material remnants in the 3 analyzed thirds. Resilon was better r...

The aim of this study was to evaluate the effectiveness of peracetic acid (PAA) in cleaning root canals contaminated with Enterococcus faecalis. Sixty first and second mandibular molars were used. Their mesiobuccal canals were prepared with the Reciproc System (VDW, Munich, Germany). The canals were irrigated with 10 mL saline during instrumentation. The teeth were randomly divided into 3 groups (n = 20), according to the irrigation solution to be used after instrumentation: group PAA (5 mL 1% PAA), group EDTA/sodium hypochlorite (NaOCl) (5 mL 17% EDTA followed by 5 mL 2.5% sodium hypochlorite), and group S (5 mL saline). Microbiological samples were collected before instrumentation and after final irrigation. Bacterial quantification was performed by counting the number of colony-forming units (CFUs/mL). The results were analyzed by the nonparametric Wilcoxon and Kruskal-Wallis tests. The 3 groups showed a significant reduction (P < .05) in CFUs/mL after final irrigation. PAA and NaOCl associated with EDTA produced a significantly higher reduction in CFUs/mL (P < .05) compared with saline. There was no statistically significant difference between PAA and EDTA + 2.5% NaOCl (P > .05). According to the results of the present study, the effectiveness of 1% PAA was similar to that of 17% EDTA + 2.5% NaOCl in cleaning curved root canals contaminated with E. faecalis.

Utilizando modelos de proteses parciais fixas de tres elementos confeccionados em metal e em In-Ceram, atraves do metodo bidimensional dos elementos finitos, analisou-se o comportamento das tensoes de Von Mises em conectores com tres formas diferentes. Observou-se que quando maior o raio de curvatura formado entre faces proximais de pontico e retentores na regiao de conectores, menores as tensoes maximas ocorridas com carregamento vertical. Em todas as sequencias de modelos, as proteses parciais fixas confeccionadas em In-Ceram demonstraram maiores concentracoes de tensoes. Os resultados da pesquisa confirmam varios estudos biomecânicos realizados dentro da odontologia atraves do metodo dos elementos finitos e tambem de fotoelasticidade, que demonstram a relacao entre variacoes de forma e concentracoes de tensoes, sugerindo possiveis alternativas tecnicas para o aumento da vida util de proteses parciais fixas, podendo ser aplicados para melhora das propriedades mecânicas de proteses parciais fixas sem metal.

A maioria dos pacientes considera a experiencia de ir ao dentista extremamente desagradavel. A apreensao ocorre devido a dor /desconforto, anestesia local e utilizacao de brocas para a remocao de carie dentaria. Adicionalmente, o barulho excessivo provocado pelos motores de alta e baixa rotacao, o qual persiste por um longo periodo de tempo durante a remocao da carie, e muito incomodo para o paciente. O metodo de remocao quimico-mecânica foi desenvolvido justamente para superar tais inconvenientes. O gel Carisolv™ e constituido por um fluido de alta viscosidade – constituido basicamente por aminoacidos – e por um fluido transparente – que contem uma solucao de hipoclorito de sodio de baixa concentracao. Os aminoacidos reagem com o hipoclorito de sodio, atraves de uma reacao de neutralizacao, facilitando a remocao da lesao de carie. O kit tambem e constituido por um conjunto de curetas sem corte especialmente desenhadas para a remocao exclusiva da dentina infectada. Este estudo apresenta uma discussao a respeito da eficiencia clinica do Carisolv™ quando utilizado em odontopediatria, apresentando-se como uma otima alternativa para a remocao de lesoes de carie. Termos de Indexacao: carie dentaria; desmineralizacao do dente; preparo da cavidade dentaria.

O processo de reparação tecidual perirradicular, após cirurgia na região apical da raiz, tem sido bem descrito [24]. A regeneração do osso trabecular acontece posteriormente à excisão óssea com formação de periósteo funcional e lâmina cortical. O sucesso da cirurgia está sujeito ...