Academic literature on the topic 'Root canal filling materials. eng'

Summary Hermetic sealing of the apical area after root end resection is essential to the success of endodontic surgery. To compare microleakage after root end resection of the two bioceramic sealers without retrograde filling - Total Fill BC Sealer and MTA Fillapex, and two materials for retrograde filling-MTA and Biodentine, using the method of penetration of dye - 2% methylene blue. Forty eight extracted single-rooted human teeth were used in this study. The resection was made at 3 mm from the root tip at an angle of 90 degree to the long axis of the tooth. The teeth were divided into 4 groups: 1st group (n = 9) - root canal obturation with Total Fill BC Sealer without retrograde filling; 2nd group (n = 8) - root canal obturation with MTA Fillapex without retrograde filling. 3rd group (n = 10) - retrograde ultrasonic cavity preparation and filling with MTA. 4th group (n = 8) - retrograde ultrasonic cavity preparation and filling with Biodentine. The outer surface of the root was covered with two layers of varnish, with the exception of the apical 3 mm and then immersed in 2% methylene blue for 72 h. The degree of penetration of the dye is measured in millimeters. The data was entered and processed with the statistical package IBM SPSS Statistics 22.0. We reject the null hypothesis when p < 0.05. With significantly higher value is the arithmetic mean of the group with the root canal obturation with Total Fill BC Sealer without retrograde filling - 2,01 mm; versus a retrograde filling with MTA - 0,68 mm and Biodentin - 0,51 mm; and no statistically significant difference with the group root canal obturation with MTA Fillapex - 1,76 mm. In the four material microleakage dye was observed, but to varying degrees.

Introduction: Reinfection of root canal treated tooth leads to endodontic failure. In such case surgical endodontic therapy is the treatment of choice which provides obturation of radicular space with 3-dimensional sealing.Objective: To evaluate and compare the sealing ability of Mineral trioxide aggregate (MTA) with Glass ionomer cement (GIC) and Super EBA (Epoxybenzoic acid) root-end filling materials.Materials & Method: 94 extracted single rooted upper anterior teeth were selected for root canal preparation and obturation. Root were apically resected 3 mm; and 3 mm deep Class-I root-end cavities were prepared. Teeth were randomly distributed into 3 groups comprising 30 teeth in each group. Group-1 was retrofilled with MTA, Group-2 with GIC and Group-3 with Super EBA. 2 positive and 2 negative control teeth were instrumented and obturated but not filled on root-end cavity. In experimental groups and positive control group the whole surface of teeth except 3 mm adjacent to resected area were covered with twocoats of nail polish but in negative control group whole surface of teeth were covered, dried, immersed in 1% methylene blue for 72 hours. Each root was sectioned labio-lingually to the long axis of root. Depth of dye penetration was evaluated by 10x stereo-microscope.Result: MTA retrograde filling showed the best hermetic seal property whereas, few GIC and Super EBA samples showed microleakage in retrograde filling. GIC showed better sealing ability than Super EBA. Conclusion: MTA has potential to provide better hermetic-seal than GIC and Super EBA as root-end filling material.

The placement of appropriate root-end filling materials in contact with periradicular tissues, with improved adaptation and biological properties is critical for the long-term success of the periapical surgery. The purpose of the present study was to evaluate and compare the bio-properties of four different root canal filling materials with respect to storage media. Two mineral trioxide aggregates: MTA-Angelus (Angelus, Londrina, PR, Brazil) and ProRoot MTA (Dentsply Maillefer, Ballaigues, Switzerland) and two glass ionomer cements: one conventional Ketac Molar (3M ESPE AG, Seefeld, Germany) and a resin reinforced core build-up glass ionomer Vitremer (3M ESPE AG, Seefeld, Germany) were evaluated. Eighty healthy single-rooted human extracted teeth without curvature and with closed apices were included in this experiment. The canals were instrumented with K-files up to size #35. Adequate irrigation was performed during preparation and instrumentation using 2.6% NaOCl. Root canals were obturated with vertically condensed gutta-percha and roots end were apically resected 3mm. The samples were randomly divided in four groups (n=20) and each group was assigned to one of the four tested materials. Three-mm depth preparations were made at root ends using cylindrical diamond burs and constant water spray, and were filled with the tested materials. The roots were then wrapped in wet gauze and placed in an incubator at 37°C for 48 hours to allow complete set of the root-end filling materials. Each group was divided in two subgroups (n=10) and stored in polypropylene sealed containers for 60 days at 37°C. Specimens of the first subgroup were immersed in 5ml of a physiological-like buffered Ca- and Mg-free solution (PBS, pH=7.4) and those of the second subgroup were in 5ml of deionized water (DW, pH 6.8) After 10 minutes of immersion and at the established endpoint times, the specimens were analyzed by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Statistical analysis was performed by t-test and one-way ANOVA (p<0.05). The morphology of cement–dentin interface in fresh restorations soaked 10 min in PBS showed the margins of all cements free from porosities or gaps. EDX elemental analyzes on MTA and ProRoot MTA revealed calcium, silica and phosphorous peaks, while on Ketac Molar and Vitremer, aluminum, silica, zinc and fluoride peaks were detected. After 60 days of immersion in PBS calcium-phosphate deposits completely covered the surface, the margin and partially also the peripheral dentin surface of MTA and Pro Root MTA. Glass ionomer cements showed the presence of thick irregular deposits (p<0.05). In deionized water, EDX analyses revealed no deposits forming after 60 days. SEM analysis showed the margins of MTA and ProRoot MTA with significant discontinuities compared with glass ionomer cements (p<0.05). Mineral trioxide aggregate cements are significantly more bioactive compared to conventional or reinforced glass ionomers upon aging in PBS. Glass ionomer cements provide more optimal adaptation to dentinal cavity walls of all cements than MTA cements when used as retrograde fillings.

Abstract The aim of this study was to evaluate the bond strength of root-end filling materials. Forty 2-mm-thick slices were obtained from human single-rooted teeth. After root canal preparation using a 1.5 mm diameter cylindrical drill, the dentinal walls were prepared by diamond ultrasonic tip (CVD T0F-2). The specimens were divided according the material (n=10): MTA Angelus (MTAA), MTA Sealer (MTAS, experimental), Sealer 26 (S26) and zinc oxide and eugenol cement (ZOE). The push-out test was performed in a mechanical test machine (EMIC DL 2000) at 1 mm/min speed. The failure type was evaluated by stereomicroscopy. The results were subjected to ANOVA and Tukey test, at 5% significance level. MTAA (19.18 MPa), MTAS (19.13 MPa) and S26 (15.91 MPa) showed higher bond strength (p<0.05). ZOE (9.50 MPa) showed the least bond strength values (p<0.05). Adhesive failure was prevalent in all groups, except for ZOE, which showed mixed failures. It was concluded that root-end filling materials MTA Angelus, MTA Sealer and Sealer 26 showed higher bond strength to dentinal walls than zinc oxide and eugenol cement after retrograde preparation.

The ideal root end filling material should form a tight seal in the root canal by adhering to the cavity walls. Several materials have been used for root end filling. The present study aims to find out and compare the bioactivity of Neo MTA Plus, Pro Root MTA White, BIODENTINE & glass ionomer cement as root end filling materials using 1% methylene blue as tracer. Materials and methods: 80 extracted human permanent maxillary anterior teeth were used in the study. They were divided into four groups. Specimens were sectioned transversely in the cervical area to separate the crown from the root. The root canal was obturated with gutta percha and zinc oxide eugenol sealers. Thereafter, each sample was resected apically by removing 3 mm of the apex and filled with different materials. Samples were kept in buffering solution at 37 °C until the recommended evaluation periods. The specimens were then suspended in 1% methylene blue for 24 h, prior to the analysis. The teeth were then sectioned, and dye penetration was examined, photographed, and evaluated under a stereomicroscope. Results: Vertical dye penetration showed significant differences across different groups. The minimum dye penetration was seen in Neo MTA plus followed by BIODENTINE, Pro Root MTA and maximum in GIC. There was no significant difference in dye penetration between Neo MTA plus and BIODENTINE both at fifteen days and one-month intervals. Conclusion: The present study suggests Neo MTA plus and BIODENTINE should be the preferred material for root end filling.

Mineral trioxide aggregate (MTA) is widely used in various dental endodontic applications such as root-end filling, furcal perforation repair, and vital pulp therapy. In spite of many attempts to improve handling properties and reduce the discoloration of MTA, the ideal root canal filling material has yet to be fully developed. The objective of this study was to investigate the setting time, mechanical properties, and biocompatibility of MTA set by a silk fibroin solution. A 5 wt% silk fibroin (SF) solution (a novel hydration accelerant) was used to set SavDen® MTA and ProRoot® white MTA (WMTA). Changes in setting time, diametral tensile strength (DTS), material crystallization, in vitro cell viability, and cell morphology were assessed by Vicat needle measurement, a universal testing machine, scanning electron microscopy (SEM), and WST-1 assay, respectively. The initial setting time of ProRoot® MTA and SavDen® MTA experienced a drastic decrease of 83.9% and 42.1% when deionized water was replaced by 5 wt% SF solution as the liquid phase. The DTS of SavDen® MTA showed a significant increase after set by the SF solution in 24 h. A human osteoblast-like cell (MG-63)-based WST-1 assay revealed that both ProRoot® MTA and SavDen® MTA hydrated using SF solution did not significantly differ (p > 0.05) in cell viability. MG-63 cells with pseudopodia attachments and nuclear protrusions represent a healthier and more adherent status on the surface of MTA when set with SF solution. The results suggest that the 5 wt% SF solution may be used as an alternative hydration accelerant for MTA in endodontic applications.

This study evaluated the bond strength of root-end filling materials to root-end cavities using a new methodology. Twenty maxillary central incisors were subjected to biomechanical preparation (#80 hand file) and sectioned transversally 2 mm short of the apex and 4 mm coronally to this point. The root cylinders were embedded in acrylic resin and positioned at 45° to the horizontal plane for preparation of root-end cavities with a diamond ultrasonic retrotip. Two groups (n=10) were formed according to the root-end filling material: MTA and Super EBA. A gutta-percha cone (#80) was tug-backed at the limit between the canal and the root-end cavity. The cavity was filled and the gutta-percha cone was removed after complete setting of the sealer. The specimens were placed in an Instron machine with the root-end filling turned downwards. The push-out shaft was inserted in the space previously occupied by the gutta-percha cone and run at a crosshead speed of 1.0 mm/min for pushing out the root-end filling material. Data were analyzed by ANOVA (α=5%). Super EBA (6.03±1.31) presented higher bond strength (MPa) than MTA (1.81±0.45) (p>0.05). There was a predominance of cohesive failures for Super EBA and mixed for MTA. The protocol of specimen preparation is effective and introduces a specific methodology for assessing bond strength of root-end filling materials to dentin. Among the materials, Super EBA presented the highest bond strength.

Root canal revascularization attempts to make necrotic tooth alive by the use of certain simple clinical protocols. Earlier apexification was the treatment of choice for treating and preserving immature permanent teeth that have lost pulp vitality. This procedure promoted the formation of apical barrier to seal the root canal of immature teeth and nonvital filling materials contained within root canal space. However with the success of root canal revascularization to regenerate the pulp dentin complex of necrotic immature tooth has made us to rethink if apexification is at the beginning of its end. The objective of this review is to discuss the new concepts of tissue engineering in endodontics and the clinical steps of root canal revascularization.

Orientador: Mario Tanomaru Filho
Banca: Milton Carlos Kuga
Banca: Fábio Luiz Camargo Villela Berbet
Banca: Celso Luiz Caldeira
Banca: Ivaldo Gomes de Moraes
Resumo: O objetivo deste estudo foi avaliar a capacidade de preenchimento de canais laterais simulados pela guta-percha e Resilon, empregando diferentes técnicas termoplastificadoras de obturação: Condensação Vertical Aquecida (CVA), Compactação Termomecânica (CT) e Sistema Obtura II (SO). Foram utilizados 135 dentes humanos unirradiculados extraídos. Após preparo biomecânico, foram confeccionados seis canais laterais simulados em suas raízes, de acordo com a técnica proposta por Venturi et al. (2005). O diâmetro desses canais foi correspondente aos instrumentos # 08 e 10, sendo estabelecidos a 2, 5 e 8 mm do comprimento de trabalho (CT). Os espécimes foram divididos em 9 grupos (n=15), sendo: Grupo I (CVA + guta-percha Dentsply), Grupo II (CVA + Resilon), Grupo III (CVA + guta-percha Odous), Grupo IV (CT + guta-percha Dentsply), Grupo V (CT + Resilon), Grupo VI (CT + guta-percha Odous), Grupo VII (SO + guta-percha Obtura Flow 150), Grupo VIII (SO + Resilon) e Grupo IX (SO + guta-percha Odous Flow). Após a realização das obturações, os espécimes foram analisados pelos métodos radiográfico e diafanização, em função do percentual de preenchimento nos canais laterais, nos três terços. Os resultados foram submetidos ao teste de Kruskal-Wallis, com 5% de nível de significância, de acordo com avaliações específicas intra-grupos: CVA (Grupos I, II e III), CTH (Grupos IV, V e VI), SO (Grupos VII, VIII e IX) e Resilon (Grupos II, V e VIII). As avaliações CVA e CTH mostraram que o Resilon apresentou maior capacidade de preenchimento nas duas análises, em relação aos demais materiais, nos terços apical e médio (p<0,05). Quanto à avaliação SO, todos os materiais apresentaram boa capacidade de preenchimento dos canais laterais em todos os terços, com exceção do terço cervical onde o Resilon foi... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The aim of this study was to evaluate the ability of gutta-percha and Resilon to fill simulated canals using different thermoplastic obturation techniques: Warm Vertical Compaction (CVA), Thermomechanical Compaction (CTE) and Obtura II System (SO). It was used 135 extracted human teeth uniradicular. After biomechanical preparation, six simulated lateral canals were prepared in the roots, according to the technique proposed by Venturi et al. (2005). The diameter of these canals was equivalent to # 08 and 10 instruments and are set at 2, 5 and 8 mm to working length (WL). The specimens were divided into nine groups (n=15), as follow: Group I (CVA + gutta-percha Denstply), Group II (CVA + Resilon), Group III (CVA + gutta-percha Odous), Group IV (CTE + gutta-percha Dentsply), Group V (CTE + Resilon), Group VI (CTE + gutta-percha Odous), Group VII (SO + gutta-percha Obtura Flow 150), Group VIII (SO + Resilon) and Group IX (SO + gutta-percha Odous Flow). After the obturation, the samples were analyzed by radiographic and clearing methods, according to percentage of filling the lateral canals, in the three thirds. The result were submitted to the Kruskal-Wallis test at 5% significance level, according to specific intra-group evaluations: CVA (Groups I, II and III), CTH (Groups IV, V and VI), SO (Groups VII, VIII and IX) and Resilon (Groups II, V and VIII). CVA and CTH assessments showed that the Resilon has great ability to fill lateral canals in the two tests, compared to the other materials, in the apical and middle thirds (p < 0.05). As for SO evaluation, all materials showed good filling capacity of the lateral canals in all thirds, except in the cervical third where Resilon was better by radiographic analysis (extension and area) and in the cervical and middle thirds for clearing analysis (extension)... (Complete abstract click electronic access below)
Doutor

Orientador: Idomeo Bonetti Filho
Banca: Márcia Carneiro Valera
Banca: Ivaldo Gomes de Moraes
Banca: Renato de Toledo Leonardo
Banca: Mário Tanomaru Filho
Resumo: Diferentes técnicas de compactação da guta-percha (GP) e cimentos oburadores podem alterar a qualidade final da obturação do canal radicular. Recentemente foi introduzido um novo modelo de análise da qualidade de obturações endodônticas baseado na mensuração da concentração da glicose que passa pela falha na obturação. Este trabalho é composto por três capítulos cujos objetivos foram: a) determinar os efeitos de variações na técnica de condensação lateral (LC) e da área do canal na qualidade da obturação; b) verificar se diferentes materiais obturadores alteram a concentração do traçador utilizado no modelo de penetração de glicose, e; c) determinar se são similares os resultados de infiltração dos mesmos espécimes avaliados pelos modelos de penetração de glicose e transporte de fluidos. No primeiro estudo sessenta caninos humanos foram instrumentados e divididos em três grupos obturados por diferentes técnicas de LC e cimento AH Plus. Uma nova técnica usando uma seqüencia de espaçadores antes da colocação de um cone acessório foi comparada com duas técnicas comumente utilizadas. As raízes obturadas foram seccionadas nos níveis 3 mm e 6 mm a partir do ápice e as secções fotografadas. Usando um software de análise de imagens, as áreas do canal e de GP em cada nível foram mensuradas e a porcentagem de área obturada por guta-percha (PGP) foi calculada. Análise múltipla de variância foi utilizada para verificar as variáveis influenciando a PGP. Teste de regressão linear foi utilizado para verificar a influência da área do canal na PGP em cada nível de secção. Em ambas as secções o canal mais largo foi 2-3 vezes maior que o menos largo. Quanto maior a área do canal, menor a PGP nos níveis 6 mm (r2=0,154, P=0,02) e 3 mm (r2=0,119, P=0,007). A PGP no nível 3 mm foi menor que a 6 mm (P=0.003). A nova técnica atingiu maior PGP que as demais em ambos os níveis (P<0.05).
Abstract: Different gutta-percha (GP) compaction techniques and root canal sealers may affect the final quality of the root canal filling. Recently, it was discussed a new method for evaluation of the quality of root fillings based on measuring the concentration of the glucose that penetrates through voids in the obturation. This work is divided in 3 chapters aiming to: a) determine the effects of different techniques and canal area on the quality of laterally compacted root fillings; b) verify whether different filling materials react with the tracer used in the glucose penetration model, and; c) determine whether leakage results of the same specimens measured by the glucose penetration and fluid transport are comparable. In the first study sixty extracted canines were instrumented to the same size and equally divided in three groups filled with laterally compacted GP cones and AH Plus sealer using different techniques. A new technique with use of a sequence of spreaders prior to the accessory cone placement was compared to two commonly used techniques. The filled roots were horizontally sectioned at 3 mm and 6 mm from the apex and micro-photographs of the cross-sections were taken. Using an image-analysis software, the canal and GP areas at each level were measured. The percentage of gutta-percha filled canal area (PGP) was calculated. A Multivariate analysis was used to account for the variables influencing the PGP. Linear regression test was used to verify the influence of canal area on PGP. At each level the largest canal was 2-3 times larger than the smallest. The larger the canal area, the lower the PGP at 6 mm level (r2= 0.154, P=0.02) and at 3 mm level (r2=0.119, P=0.007). The PGP at 3 mm was lower than at 6 mm (P=0.003). The new technique achieved higher PGP than other techniques (P=0.00002).
Doutor

Resumo: O propósito do presente estudo foi avaliar os cimentos endodônticos Acroseal, AH Plus, Epiphany e Polifil (cimento endodôntico experimental), no que se refere às propriedades de solubilidade e desintegração, alteração dimensional e resistência à compressão. Os testes seguiram a Norma ISO 6876-2, de 2001 e ISO 9917-1, de 2003. Nos testes de solubilidade e desintegração foram utilizados moldes de teflon (4mm de espessura, 12mm de diâmetro interno e 2mm de parede) preenchidos com cimentos endodônticos e contendo perfuração com fio de nylon para suspensão das amostras. Os espécimes foram levados à estufa até a presa dos materiais. Em seguida, as amostras hidratadas e desidratadas tiveram sua massa mensurada imediatamente após sua retirada da estufa, e após períodos de 24h, 48h, 72h, 7, 14, 30, 60 e 90 dias. A solubilidade dos cimentos endodônticos foi identificada pela alteração da massa de cada amostra, expressa como o percentual de massa perdida em comparação à massa inicial. A desintegração foi identificada visualmente, pela observação de resíduos nos recipientes e pela turbidez da água destilada. Nos testes de alteração dimensional e resistência à compressão foram utilizados moldes de teflon (12mm de espessura e 6mm de diâmetro). Os moldes foram preenchidos com cimentos endodônticos e levados à estufa até a tomada de presa, então foram removidos dos moldes e, para os testes de alteração dimensional, suas dimensões foram medidas, no sentido longitudinal, com paquímetro digital, imediatamente após sua retirada da estufa e após períodos de 24, 48 e 72 horas, 7, 14, 30, 60 e 90 dias de armazenamento. A alteração dimensional foi identificada como a percentagem de alteração volumétrica no final de cada período, em comparação ao período inicial.
Abstract: Considering all the steps of the endodontic therapy, their success depend on the root canals sealing when the professional uses an endodontic sealer that gathers physical, chemical and biological properties. The aim of this study was to evaluate the endodontic sealers: Acroseal, AH Plus, Epiphany and a castor-oil based experimental sealer (Polifil) concerning the properties of solubility and disintegration, dimensional change and compressive strength. All of these tests were supposed to follow the ISO Specification 6876-2, 2001 and ISO Specification 9917-1, 2003. To perform the solubility and disintegration tests teflon rings (4 mm thickness, 12 mm of internal diameter, and 2 mm height) filled with the endodôntico sealers were used, containing perforations that allow a nylon wire passing through it, in order to get the specimens raised up. They were storaged in the oven under 37º C up to the setting time. The specimens were hydrated and dehydrated to be weighted for 24h, 48h, 72h, 7, 14, 30, 60 and 90 days. The solubility of the endodontic sealers was identified as a percentage obtained through the difference between the last measure of weight and the initial one. The disintegration were visually identified by observating the residues and the water's whirlwind. Teflon moulds (12 mm thickness and 6mm diameter) were used in dimensional change and compressive strength tests. They were filled with the endodontic sealers and storaged in the oven under 37º C up to the setting time. Afterwards, the moulds were removed and then, for the dimensional change test, they were measured under the longitudinal position with digital pachymeter for 24h, 48h, 72h, 7, 14, 30, 60 and 90 days. The dimensional change was identified as a percentage of the volumetrical change gotten in each time, compared with the first specimen.
Orientador: Idomeo Bonetti Filho
Coorientador: Luís Geraldo Vaz
Banca: Yara Teresinha Corrêa Silva Souza
Banca: Roberto Miranda Esberard
Mestre

Orientador: Mário Tanomaru Filho
Banca: Luis Geraldo Vaz
Banca: Idomeo Bonetti Filho
Banca: Marco Antônio Hungaro Duarte
Banca: Marcus Vinicius Reis Só
Resumo: O objetivo desse estudo foi a avaliação da liberação de íons cálcio, do pH e da adesividade de alguns cimentos utilizados em Endodontia: Sealapex (G1), Sealer 26 (G2), Acroseal (G3), Epiphany (G4), MTA Branco (G5), Endo CPM Sealer (G6). Após a espatulação, os materiais foram inseridos em tubos de polietileno medindo 1,5 mm de diâmetro interno e 1 cm de comprimento com ambas extremidades abertas e imersos em frascos de vidro contendo 10 mL de água ultra pura. Nos períodos de 2, 6, 12, 24 e 48 horas, 7, 14 e 28 dias foram realizadas as análises, sendo o tubo contendo o cimento transferidos para novo frasco a cada período. O pH e a liberação de íons cálcio foram avaliados, respectivamente por meio de pH metro e espectrofotometria de absorção atômica. Para a avaliação da adesividade dos cimentos endodônticos às paredes dentinárias, os canais radiculares de 28 dentes humanos uniradiculados foram dilatados com brocas de Gates Glidden número 1, 2 e 3 e brocas largo número 1, 3 e 5. As raízes foram cortadas em máquina de corte para confecção de discos de 2 mm de espessura. Durante o preparo e depois da secção os espécimes foram irrigados com solução de hipoclorito de sódio a 2,5% e com EDTA a 17 % para a remoção da smear layer. Após a divisão aleatória nos grupos experimentais, os espécimes foram secos e preenchidos com os cimentos endodônticos, sendo mantidos em estufa a 37oC e 95% de umidade relativa do ar por 48 hs. Em seguida, cada conjunto dentina/cimento endodôntico foi submetido ao teste push-out em uma máquina de ensaio mecânico e a tensão necessária para a remoção do cimento medida em Mega Pascal (MPa). Após a coleta dos dados estes foram submetidos à análise estatística de Análise Variância e teste Tukey, com nível de 5% de significância. Os maiores valores de pH foram obtidos pelos G6, seguido por G2 e G5 após 2 horas (P<0,05)... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The aim of this study was to evaluate in vitro the pH, calcium ion release and adhesiveness provide by 6 endodontic filling materials: Sealapex (G1), Sealer 26 (G2), Acroseal (G3), Epiphany (G4), White MTA (G5), Endo CPM Sealer (G6). After manipulation, the sealers (n=10) were placed in tubes with 10 mm-long and 1.5 mm in diameter and immediately immersed in a glass flask containing 10 ml of ultra pure water, which was hermetically sealed and stored at 37°C. At 2, 6, 12, 24 and 48 hr, and at 7, 14 and 28 days after mixing the tubes were moved to new flask with fresh solution and the water in which they were immersed was analyzed for pH with a pH meter and for released calcium by atomic absorption spectrophotometry. To evaluate the adhesiveness of the sealers to the root canal wall, 28 teeth were enlarged to size 5 Largo drill and cut in a cutting machine to create 2 mm thickness slices. During all this procedure the root canal was irrigated with sodium hypochlorite 2.5% and with EDTA 17% to remove the smear layer. The slices were randomly allocated to one of the groups, dried and filled with the sealers and kept in a controlled environment (37oC and 95% humidity) to allow the setting of the sealers. After that, the slice root/endodontic sealer was submitted to push out test in a mechanical testing machine and the results were expressed in Mega Pascal (MPa). The results obtained at each time were statistically evaluated. After 2 hours the uppermost pH was found in the G6, followed by G2 and G5 (P<0,05). From 6 h till 24 h the highest value were observed in groups G5, G6 and G2. After 48 hours, the pH of groups G5 and G6 were stood out. Finally from the 7th to 28th days of evaluation G2, G5 and G6 presented the utmost pH. With regards to calcium ions release in beginning periods the G6 was statistical significantly from the other groups until the 7th day (P<0.05)... (Complete abstract click electronic access below)
Doutor

Orientador: Mario Roberto Leonardo
Banca: Lea Assed Bezerra da Silva
Banca: Antonio Carlos Bombarda
Resumo: O objetivo deste estudo foi o de avaliar, in vivo, a biocompatibilidade e a influência da infiltração, no sentido coroa/ápice, na reparação dos tecidos apicais e periapicais pós-tratamento endodôntico, utilizando dois diferentes materiais obturadores: o cimento Sealapex e um sistema resinoso de obturação de canal radicular denominado de sistema Epiphany/Resilon. Os resultados mostraram que o sistema Epiphany/Resilon apresentou resposta tecidual apical e periapical melhor que o cimento Sealapex, independente da presença ou não de restauração coronária, em todos os aspectos estudados. O sistema Epiphany/Resilon com restauração coronária apresentou melhores resultados que o mesmo sistema sem restauração coronária. O cimento Sealapex sofreu influência da infiltração coronária, apresentando, em todas as variáveis estudadas, os piores resultados, quando exposto ao meio bucal.
Abstract: The objective of this study was to evaluate, in vivo, the biocompatibility and the leakage influence, in the crown-apex direction, in the endodontic post-treatment repairing of apical and periapical tissues, using two different filling materials: Sealapex sealer and a resinous cement of root canal filling - Epiphany/Resilon. The results showed that Epiphany/Resilon system presented apical and periapical tissue response better than Sealapex independent of presence or no of the coronary restoration, in all studied aspects. Epiphany/Resilon system, with coronary restoration presented better results than of the same system without coronary restoration. Sealapex was influenced by the coronary exposition to oral environment, presenting the worst results in all studied variables.
Mestre

Orientador: Renato de Toledo Leonardo
Banca: Celso Kenji Nishiyama
Banca: Abílio Albuquerque Maranhão de Moura
Banca: Iracilda Zeppone Carlos
Banca: Idomeo Bonetti Filho
Resumo: Analisou-se a citotoxicidade dos seguintes cimentos: Endofill, Sealapex e Polifil, quanto à liberação de óxido nítrico (NO) e peróxido de hidrogênio (H2O2) em culturas de macrófagos peritoneais de camundongos e também utilizamos um método de análise colorimétrica usando M.T.T. Concluiu-se que as considerações presentes após os resultados, discussão e constatação os cimentos que apresentaram o menor nível de citotoxicidade foi o Endofill, seguido da equivalência de liberação de Polifil e Sealapex, embora todos foram menos citotóxicos que o Grupo Controle Zimosan-A para H2O2 e o LPS para o NO.
Abstract: It was analyzed the citotoxicity of the following cements Endofill, Sealapex, and Poliol regarding the nitric oxide (NO) release and the hydrogen peroxide (H2O2) in the peritoneais macrophages medium of mice in different concentrations and we have also analyzed a colorimetric method using the M.T.T. It was concluded from the considerations which were present in the results, discussion, and verification that the cement which presented the lowest citotoxicity level was the Sealapex followed by the Polifil and the Endofill, although all of them were less citotoxic than the Zimosan-A control group for H2O2 and the LPS for the NO.
Doutor

Orientador: Iracilda Zeppone Carlos
Banca: Renato de Toledo Leonardo
Banca: Celso Kenji Nishiyama
Resumo: Avaliou-se a citotoxicidade dos cimentos Topseal, EndoRez, Tubli-Seal e Kerr Pulp Canal Sealer E.W.T. quanto a liberação de derivados do oxigênio no contato cimento/cultura de macrófagos peritoneais de camundongos. Respectivamente os cimentos que mais liberaram H2O2 na concentração de 9 mg/ml foi o Topseal > Zimosan > EndoRez > Tubli-Seal = Kerr Pulp E.W.T. e na concentração de 18 mg/ml foi o Topseal > Zimosan = EndoRez > Tubli-Seal > Kerr Pulp E.W.T. Os que mais liberaram NO na concentração de 9 mg/ml foi o LPS > Topseal > Kerr Pulp E.W.T. > Tubli-Seal = EndoRez e na concentração de 18 mg/ml foi o LPS > Topseal = Kerr Pulp E.W.T. > Tubli-Seal > EndoRez.
Abstract: It was evaluated the citotoxicity of the sealers Topseal, EndoRez, Tubli-Seal and Kerr Pulp Canal Sealer after exposure to rat peritoneal macrophage culture, due to oxigen derivate liberation. Respectively, the sealer that, liberated more H2O2 at 9 mg/ml concentration were Topseal > Zimosan > EndoRez > Tubli-Seal = Kerr Pulp E.W.T. and in concentration of 18 mg/ml were Topseal > Zimosan = EndoRez > Tubli-Seal > Kerr Pulp E.W.T. The greatest liberation of in NO concentration of 9 mg/ml were LPS > Topseal > Kerr Pulp E.W.T. > Tubli-Seal = EndoRez and in concentration of 18 mg/ml were LPS > Topseal = Kerr Pulp E.W.T. > Tubli-Seal > EndoRez.
Mestre

Uvod: Sistem kanala korena je složena celina koja pored glavnog korenskog kanala sadrži brojne lateralne, sekundarne, akcesorne kanale, apikalne istmuse i delte, kao i razgranatu mrežu dentinskih tubula. Kako korensko kanalni sistem ne može biti u potpunosti očišćen i dezinfikovan postojećim tehnikama instrumentacije, irigacije i intrakanalne medikacije, uloga kanalnog punjenja se ogleda u postizanju trodimenzionalne opturacije kanalnog prostora, ”pečaćenju” preostalih bakterija i onemogućavanju njihovog prodora u periradikularna tkiva. Ispitivanjem reoloških svojstava mogu se bliže odrediti karakteristike tečenja i viskoelastična svojstva endodontskih materijala. Definisanje i razumevanje reoloških svojstava endodontskih silera u različitim uslovima doprinosi pravilnom rukovanju materijalom shodno primenjenoj tehnici opturacije. Cilj istraživanja: ispitivanje viskoelastičnih svojstava tri različita endodontska silera, uključujući i tečenje / prodor silera u dentinske tubule u kombinaciji sa različitim tehnikama opturacije. Materijal i metode: Ukupan uzorak činilo je 132 meziobukalna i meziolingvalna kanala korena prvih donjih molara. Nakon preparacije kanala krunično-apeksnom tehnikom i ProTaper endodontskim instrumentima, uzorak je podeljen u tri grupe u zavisnosti od ispitivanog silera (AH Plus, Sealapex i EndoREZ) i dodatno u četiri podgrupe shodno primenjenoj tehnici opturacije (hladna lateralna kompakcija, monokona tehnika, opturacija sa čvrstim nosačem gutaperke i topla vertikalna kompakcija), što je činilo ukupno 12 grupa po 11 kanala. Nakon opturacije, uzorci su poprečno presečeni na rastojanju 3, 5 i 8mm od anatomskog foramena, kako bi se dobili preseci koji odgovaraju apikalnoj, srednjoj i koronarnoj trećini kanala. Koronarne površine preseka su analizirane skening elektronskim mikroskopom (SEM). Mesto najdubljeg tubularnog prodora silera je izmereno i izraženo u mikrometrima i procentualno u odnosu na ukupno rastojanje dentinski zid kanala - spoljašnja površina korena. Viskoelastična svojstva endodontskih silera su ispitana na dinamičkom oscilatornom reometru, frequency sweep testom, na četiri različite temperature: 25°C, 35°C, 40°C i 65°C. Rezultati: Tehnike opturacije silerom AH Plus koje primenjuju toplotu i pritisak daju značajno višu dubinu prodora silera u dentinske tubule u odnosu na tehnike koje ne primenjuju. Primena toplote i pritiska tokom opturacije silerom Sealapex nema značajnu ulogu u dubini prodora silera u dentinske tubule. Tehnike opturacije silerom EndoREZ koje ne primenjuju toplotu i pritisak daju značajno višu dubinu prodora silera u dentinske tubule u odnosu na tehnike koje primenjuju. Dubina prodora sva tri ispitivana endodontska silera u dentinske tubule je najviša u koronarnoj trećini, zatim srednjoj i značajno je niža u apikalnoj trećini kanala korena. AH Plus, Sealapex i EndoREZ ispoljavaju viskoelastični karakter sa dominantnim vrednostima elastičnog modula u odnosu na vrednosti viskoznog modula, na svim zadatim temperaturama, u opsegu primenjenih frekvencija i napona smicanja. Kompleksni viskozitet svih ispitivanih silera opada sa porastom frekvencije, na svim zadatim temperaturama. Sa porastom temperature kompleksni viskozitet silera AH Plus opada, dok za silere Sealapex i EndoREZ raste. Korelacionom analizom ustanovljena je jaka negativna korelacija između kompleksnog viskoziteta ispitivanih silera i dubine prodora u dentinske tubule: opadanjem kompleksnog viskoziteta dubina prodora silera u dentinske tubule raste. Zaključak: Odabir endodontskog silera treba da je zasnovan na tehnici opturacije koja se primenjuje.
Introduction: The root canal system has a complex anatomy with main root canal and many lateral, secondary, accessory canals, apical isthmuses and deltas, as well as numerous branched dentinal tubules. Due to its complexity, the root canal system cannot be completely cleaned, shaped and disinfected using available techniques of instrumentation, irrigation and intracanal medication. The aim of root canal filling is to achieve a three-dimensional obturation of the root canal space, entomb residual bacteria and prevent their penetration into the periradicular tissue. Defining and understanding the rheological properties of endodontic sealers in different conditions contributes to the proper handling of the material according to the obturation technique applied. The aim: testing the viscoelastic properties of three different endodontic sealers, including the flow / sealer penetration into dentinal tubules in combination with different obturation techniques. Materials and Methods: The total sample consisted of 132 mesiobuccal and mesiolingual root canals of first mandibular molars. After root canal preparation using ProTaper endodontic instruments, in crown-down manner, the sample is divided into three groups depending on the tested sealers (AH Plus, Sealapex and EndoREZ) and additionally into four subgroups according to the obturation technique applied (cold lateral compaction, single-cone technique, carrier – based obturation and warm vertical compaction), making a total of 12 groups of 11 canals. After root canal obturation, the samples were sectioned horizontally at 3, 5 and 8mm from the anatomical foramen, in order to get the sections that correspond to the apical, middle and coronary third of the canal. The coronal surfaces of the sections were analyzed using scanning electron microscopy (SEM). The maximum depth of sealer penetration was measured and expressed in micrometers and as a percent of the total distance: canal dentinal wall - the outer surface of the root. The viscoelastic properties of endodontic sealers were measured using frequency sweep test on dynamic oscillatory rheometer, at four different temperatures: 25°C, 35°C, 40°C and 65°C. Results: Obturation techniques with AH Plus that applied heat and pressure produced a significantly higher depth of sealer penetration into dentinal tubules as compared to techniques that did not apply. The application of heat and pressure during obturation with Sealapex had no a significant role in the depth of sealer penetration into dentinal tubules. Obturation techniques with EndoREZ that did not apply heat and pressure produced a significantly higher depth of sealer penetration into dentinal tubules as compared to techniques that applied. The depth of penetration of all three endodontic sealers into dentinal tubules was the highest in the coronary third, followed by the second and was significantly lower in the apical third of the root canal. AH Plus, Sealapex and EndoREZ exhibited viscoelastic character with dominant values of elastic over viscous modulus, at all specified temperatures, in the range of applied frequencies and shear stresses. Complex viscosity of all sealers decreased as the frequency increased at all temperatures. AH Plus showed decreased viscosity as the temperature increased, while Sealapex and EndoREZ demonstrated opposite behavior. Correlation analysis has established a strong negative correlation between the complex viscosity of the tested sealers and the depth of penetration into dentinal tubules: the decrease of complex viscosity increase the depth of sealer penetration into dentinal tubules. Conclusion: The choice of endodontic sealer should be based on the obturation technique applied.

Već izvesno vreme u stručnoj literaturi vodi se rasprava o biokompatibilnosti materijala koji se koriste u periapikalnoj hirurgiji. Pored biokompatibilnosti, od materijala za retrogradnu opturaciju kanala korena zuba se očekuje da spreči prodor bakterija iz kanalnog sistema u okolna tkiva. Kvalitetno rubno zaptivanje, odnosno adekvatna marginalna adaptacija su među najznačajnijim faktorima za dugoročan uspeh tretmana. Cilj ovog istraživanja je bio ispitati biokompatibilnost i utvrditi da li postoji razlika u biokompatibilnosti između mineral-trioksid agregata, trikalcijum-silikatnog cementa i amalgama na osnovu tri standadna testa citotoksičnosti, kao i utvrditi marginalnu adaptaciju ispitivanih materijala za retrogradno zatvaranje kanala korena zuba. Materijali i metode: Eksperimentalni deo istraživanja je podeljen na dva dela. U prvom delu istraživanja je vršeno ispitivanje biokompatibilnosti materijala, dok je u drugom delu vršeno ispitivanje marginalne adaptacije na osnovu mikrofotografija dobijenih skening elektronskim mikroskopom. Ispitivanje biokompatibilnosti je izvršeno na dve ćelijske linije, liniji mišjih fibroblasta (L929) i liniji humanih fibroblasta (MRC-5). U eksperimentima su korišćene samo žive (vijabilne) ćelije. Broj ćelija i njihova vijabilnost je određena testom odbacivanja boje sa 0,1% tripan plavim. Vijabilnost ćelija korišćenih u eksperimentu je bila veća od 90%. Biokompatibilnost sve tri vrste materijala je ispitana na osnovu standardnih testova biokompatibilnosti: DET test, MTT test, Agar difuzioni test. Ispitivanje marginalne adaptacije je sprovedeno na 90 ekstrahovanih jednokorenih zuba interkaninog sektora gornje vilice sa intaktnom pulpom, završenim rastom korena, bez frakture i resorpcije korena zuba. Izvršena je endodontska obrada svih zuba i nakon toga su zubi ostavljeni u vlažnoj sredini na 48h, da bi se sprečile frakture prilikom sečenja. Nakon mehaničko medikamentozne obrade i opturacije kanala korena zuba je vršena resekcija vrha korena zuba 3mm, a nakon toga su svi zubi preparisani do dubine od 3 mm unutar kanala, ultrazvučnim nastavcima (EMS, miniMaster Piezon scaler). Zubi su naizmenično podeljeni u 3 grupe (30 zuba po grupi). Prvu grupu čine zubi kojima je apikalni kavitet biti ispunjen amalgamom, u drugoj grupi, apikalni kavitet je ispunjen MTA, a u trećoj trikalcijum-silikatnim cementom. Nakon retrogradne opturacije, zubi su ostavljeni u vlažnoj sredini 48h, do potpunog vezivanja ispitivanih materijala. Nakon vezivanja ispitivanih materijala, zubi su sečeni longitudinalno, finom dijamantskom šajbnom. Marginalna adaptacija ispitivanih materijala je procenjena skening elektronskim mikroskopom (SEM). Pripremljeni uzorci su posmatrani pod uvećanjima 30x, 40x, 80x i 100x. Uvećanje 30x je rađeno radi prikaza celokoupnog retrogradnog punjenja na jednom snimku, tj. spoja materijal-zub. Nakon toga je napravljeno više uzastopnih snimaka sauvećanjem 80x do pune dužine materijala. Na taj način je utvrđeno postojanje i izvršeno merenje marginalne pukotine u mikrometrima. Merenja ukupne dužine marginalne pukotine u mikrometrima u 5 tačaka sa obe strane preparata su vršena u softverskoj aplikaciji Image J software (National Institutes of Health, Bethesda, USA). Tačke su izabrane tako da tačka 1a i tačka 5a predstavljaju gornju i donju ivicu preparata. Tačka 3a predstavlja sredinu rastojanja između tačke 1a i tačke 5a. Tačka 2a i tačka 4a predstavljaju sredinu razmaka između tačke 1a i 3a, odnosno 3a i a5. Tačke 1b-5b su naspramne tačke. Rezultati biokompatibilnosti ukazuju na visok stepen ćelijske kompatibilnosti svih ispitivanih materijala. Međutim, DET testomnije utvrđena statistički značajna razlika u citotoksičnosti između istovetnih ispitivanih materijala u obe ćelijske linije, niti između sva tri ispitivana materijala u obe ćelijske kulture.Poređenjem rezultata MTT testa nakon 24h i 48h, kao i nakon 48h i 72h uočava se da su dobijene srednje vrednosti indeksa citotoksičnosti kod sva tri ispitivana materijala i na obe ćelijske linije manje nakon 48h, odnosno nakon 72h, što ukazuje na oporavak ćelijskog metabolizma. Poređenjem rezultata nakon 24h i nakon 72h, uočava se znatno veći pad vrednosti indeksa citotoksičnosti nakon 72h kod sva tri ispitivana materijala i na obe ćelijske linije. U kulturi ćelija MRC5, kod sva tri ispitivana materijala postoji statistički značajna razlika između indeksa citotoksičnosti izmerenog nakon 24h i nakon 72h, kao i u kulturi ćelija L929. Agar difuzionim testom nije uočena dekolorizacija, niti liza ćelija ispod ispitivanih materijala. Ćelijski odgovor je 0/0 što ukazuje da ovim testom nije utvrđeno postojanje citotoksičnog efekta ispitivanih materijala na ćelijske linije L929 i MRC-5. Ispitivanje marginalne adaptacije materijala je vršeno na osnovu mikrofotografija dobijenih skening elektronskim mikroskopom.. Najpre su testirane razlike na prvoj tački merenja. Rezultati ovog testa pokazuju da postoje značajne razlike između materijala i da amalgam ima značajno više vrednosti izmerenih pukotina u odnosu na preostala dva materijala, dok se vrednosti za MTA i biodentin međusobno značajno ne razlikuju. Kao još jedna referentna tačka uzeta je tačka merenja 5. I u odnosu na vrednosti u ovoj tački merenja zabeležene su značajne razlike između materijala. Post hoc Mann-Whitney test pokazuje da se amalgam značajno razlikuje od preostala dva materijala, dok nema značajnih razlika između MTA i biodentina. Na osnovu medijane može se videti da amalgam ima niže vrednosi u ovoj tački merenja u odnosu na preostala dva materijala. U tačkama 2-4, kao i u tačkama 1-5 (ukupno), ne postoji statistički značajna razlika u marginalnoj adaptaciji ispitivanih materijala. Rezultati biokompatibilnosti ukazuju na visok stepen ćelijske kompatibilnosti svih ispitivanih materijala. Rezultati sva tri testa pokazuju da ne postoji statistički značajna razlika u citotoksičnosti između ispitivanih materijala. MTT test pokazuje da u obe ćelijske kulture, kod istovetnih ispitivanih materijala postoji statistički značajna razlika između indeksa citotoksičnosti izmerenog nakon 24h i nakon 72h. Rezultati ispitivanja marginalne adaptacije pokazuju da u tački 1 najgore zaptiva amalgam, dok izmedju MTA i biodentina nema razlike. U tački 5 najbolje zaptiva amalgam.
Biocompatibility of materials, deployed in periapical surgery, has been a subject of debate in referential literature for some time now. Apart from biocompabillity, root end filling materials are expected to prevent bacteria from entering the surrounding tissue from canal system. The most important factors for successful long term treatment include marginal seal, i.e. adequate marginal adaptation. The aim of this research was to examine biocompatibility and establish the potential difference in biocompatibility between mineral trioxide aggregate, tricalcium silicate cement and dental amalgam according to three cytotoxicity tests, but also to corroborate marginal adaptation of the materials in question for retrograde seal of a root canal. Materials and methods: The experimental part of the research is divided in two parts. In the first part of the research biocompatibility of the materials was examined, while the examination of the marginal adaptation based on the micro images from scanning electron microscope was conducted in the second part. The examination of biocompatibility was executed on two cell lines, mouse fibroblast cell line (L929) and human cell line (MRC-5).Biocompatibility of all three types of material was examined based on three standard biocompatibility tests: DET test, MTT test, Agar diffusion test.The examination of marginal adaptation was carried out on 90 single-rooted tooth extractied human teeth of the intercanine sector of maxilla with intact pulp, mature apices, without root fractures or resorption. All teeth were endodontically treated. After the extirpation, irrigation and opturation, the resection of 3mm of root apex and retrograde preparation with ultrasonic instruments up to 3 mm depth inside the canal was done. Teeth were divided in three groups alternately. The First group include teeth which apical cavitation was filled with amalgam, in the Second group apical cavitation was filled with MTA, and in the Third group with tricalcium silicate cement. After the complete setting of the materials, teeth were cut in longitudinal manner, with fine, diamond tool. Marginal adaptation of the materials was assessed through scanning electron microscope (SEM). Software application Image J software was deployed to measure the total length of marginal fissure in micrometers in 5 pointson both sides of the preparation . The results of biocompatibility indicate high degree of cell compatibility of all tested materials. DET test did not assert any statistically significant difference in cytotoxicity between the same tested materials in both cell lines, nor between all three tested materials in both cell cultures. Comparing the results of MTT test after 24h and 48h, and 48h and 72h, it is noted that middle value of cytotoxicity index with all three tested materials and on both cell lines is lower after 48h, and after 72h, indicating the recovery of cell metabolism. In both cell cultures, with all three tested materials there is statistically significant difference between measured cytotoxicity indices after 24h and after 72h. Agar diffusion test did not show decolorization, nor cell lysis underneath the tested materials, which means that cytotoxic effect was not asserted on cell lines L929 i MRC-5. The examination of marginal adaptation was conducted according to micro images gained by scanning electron microscope. The results in the measure point 1 indicate there are significant differences between materials, and amalgam has significantly higher values of the measured fissures in relation to remaining two materials, whereas values for MTA and biodentine do not differ significantly. In measure point 5 significant differences were noted. Post hoc Mann-Whitney test shows that amalgam has lower values of the tested fissures in this measure point in relation to two other materials, while there were no significant differences between MTA i biodentine. In points 2-4, as well as points 1-5 (in total), there were no statistically significant differences in marginal adaptation of the examined materials. The results of all three tests show that there is no statistically significant difference in cytotoxicity between examined materials. MTT test shows that there is, in both cell cultures, with the same examined materials , statistically significant difference between cytotoxicity indices measured after 24h and after 72h. The results of the examination of marginal adaptation show that in point 1 amalgam has the worst seal, whereas between MTA and biodentine there is no difference. In point 5 amalgam has the best seal.

The three dimensional obturation of root canals is vital and cannot be overstated. The attainment of a fluid-tight seal in a root canal system is very important for the longterm success of endodontic treatment. A number of different materials have been used for obturation. Gutta percha is the most common root filling material in use today. It is used as the core material in combination with sealers of different compositions. Despite gutta percha has enjoyed a long history of use and his success rate; it does not offer all of the properties of an ideal root canal filling materials. New root canal filling materials have been developed. These include resin-based (EndoRez and RealSeal systems) and silicone-based (Guttaflow') filling materials. This study aimed to investigate properties of these new root canal filling materials and compare it to gutta percha and a zinc oxide based sealer (TubliSeal).