Analysis of the physicochemical properties, cytotoxicity and volumetric changes of AH Plus, MTA Fillapex and TotalFill BC Sealer

To evaluate the physicochemical properties and cytotoxicity of AH Plus, MTA Fillapex and TotalFill BC Sealer. Volumetric changes were also evaluating using micro-computed tomography (micro-CT). Radiopacity and flow were evaluated in accordance with the ISO 6876, while setting time was evaluated in accordance with the ASTM- C266-08 specifications. The release of Ca2+ ions and pH were measured with spectrophotometer and pH meter, respectively, after different time intervals (1h, 3h, 24h, 72h, 168h, and 360h). Cytotoxicity was evaluated by MTT reduction assay to check 3T3 cells viability at 24, 48 and 72 hours. Volumetric change was evaluated by micro-CT, by using 30 acrylic teeth, filled with gutta-percha cones and the tested root canal sealer. The samples were evaluated after 168h, 360h and 720h of immersion in distilled water. Data were statistically analyzed by one-way ANOVA and Tukey test or by Kruskal-Wallis and Dunn tests (P<0.05). MTA Fillapex and TotalFill BC Sealer showed lower radiopacity than AH Plus (P<0.05). The MTA Fillapex showed the highest flow, while AH Plus showed the lowest flow (P<0.05). The initial and final setting time of AH Plus were lower than MTA Fillapex and TotalFill BC Sealer (P<0.05). In general, TotalFill BC Sealer presented higher Ca2+ ion release and pH than the other tested sealers. TotalFill BC Sealer also showed overall lower cytotoxicity when compared to the other sealers. Volumetric change of AH Plus and TotalFill BC Sealer was lower than MTA Fillapex (P<0.05). AH Plus, MTA Fillapex and TotalFill BC Sealer showed slight differences in the physicochemical properties and cytotoxicity, but all suitable for an endodontic sealer. However, AH Plus and TotalFill BC Sealer showed low volumetric changes when compared to MTA Fillapex

Propriedades físico-químicas e análise da citotoxicidade de 5 diferentes cimentos endodônticos

The aim of this study was to analyze the radiopacity, setting time, flowability, pH, calcium ion release, solubility and cytotoxicity of bioceramic cements Totalfill BC Sealer and Totalfill BC RRM, and compare them with AH Plus, MTA Fillapex and MTA Angelus. The groups were divided and compared among them according to the filling and retro-filling cement functions. Totalfill BC Sealer was compared with AH Plus and MTA Fillapex; and Totalfill BC RRM retrofilling cement with MTA Angelus. For radiopacity analysis, specimens were placed in metal rings measuring 10x1 mm placed on occlusal film together with the aluminum scale. Digora 1.51 software was used to evaluate the digitized images and determine radiographic density. Setting time was tested in accordance with the American Society for Testing and Materials C266-08 standard specifications, but specimens were fabricated in accordance with the International Organization for Standardization 6876: 2001. Flow was tested in accordance with ANSI/ADA No.57/200 specifications. In total 30 acrylic teeth were filled with filling-cements and 20, with (retrograde cavity) retro-filling cements. All teeth were immersed in ultrapure water for pH and calcium ion release measurement (atomic absorption spectrophotometer) for time intervals of 1, 3, 24, 72, 168 and 360 hours. Solubility was tested by scanning and digitizing 50 acrylic teeth twice by Micro- CT, before and after immersion in ultrapure water for time intervals of 168, 360 and 720 hours. The images were reconstructed and volume (mm3) values of samples obtained by means of CTan software (CTan v1.11.10.0, SkyScan). The in vitro effects on cells were analyzed at concentrations of 100, 50, 10, 5, 1 mg/mL, and 0 mg / mLnegative control group and recorded in time intervals of 24, 48 and 72 hours by MTT reduction assay. The results were statistically analyzed by the ANOVA, Tukey, Kruskal-Wallis and Dunn tests (P<0.05). All radiopacity values according to ISO 6876/2001, AH Plus (7.86 mm Al) being the most radiopaque followed by Totalfill BC Sealer (4.84 mm Al), MTA Fillapex (3.41 mm Al), Totalfill BC RRM (6.8 mm Al), and MTA Angelus (6.7 mm Al). The following values were the initial and final setting time (in hours), respectively: AH Plus (8 and 15); Totalfill BC Sealer (11 and 24); MTA Fillapex (13 and 26); MTA Angelus (10 and 120 minutes) and Totalfill BC RRM (3 hours and 22 hours). In flow analysis, the cements behaved as follows: MTA Fillapex (47 mm), Totalfill BC Sealer (41.5 mm), Totalfill BC RRM (33.5 mm), AH Plus (33 mm) e MTA Angelus (17.5 mm) (p < 0.05). pH analysis showed in general the lowest values for AH Plus cement, followed by Totalfill BC RRM, MTA Angelus, MTA Fillapex and Totalfill BC Sealer. AH Plus showed the highest Ca2+ release in time interval 1 hour (1.38 mg/L); MTA Fillapex, in 360 hours (3.81 mg/L); MTA Angelus, 1 hour (1.38 mg/L); Totalfill BC Sealer, 360 hours (6.77 mg/L) and Totalfill BC RRM, 360 hours (3.81 mg/L). Almost all the sealers presented solubility lower than 3% in all periods, as recommended by ISO 6876/2001. Whereas, the MTA Fillapex solubility value was higher than 5% in all periods. Relative to cytotoxicity, all the cements were shown to be toxic at the concentration of 100 mg/mL, however, Totalfill BC Sealer and Totalfill BC RRM showed the best cell viability result compared with the other cements tested. We concluded that all root canal filling and root retro-filling complied with the requisites of radiopacity, setting time, flow, pH, calcium ion release, solubility and cytotoxicity. With the exception of the MTA Fillapex that not only fulfilled the requirement of solubility. Of the sealers, Totalfill BC Sealer was outstanding: it showed the highest pH and Ca2+ release, and lowest cytotoxicity. Among the retrofilling cements, Totalfill BC RRM maintained its high pH, higher Ca2+ release, and lower cytotoxicity.O objetivo do presente estudo foi analisar a radiopacidade, tempo de presa, escoamento, pH, liberação de íons cálcio, solubilidade e citotoxicidade dos cimentos biocerâmicos Totalfill BC Sealer e Totalfill BC RRM e compará-los ao AH Plus, MTA Fillapex e MTA Angelus. Os grupos foram divididos e comparados entre si de acordo com as funções dos cimentos de obturação e retro-obturação. Comparamos o cimento obturador Totalfill BC Sealer com os cimentos AH Plus e MTA Filapex, e o cimento retrobturador Totalfill BC RRM com o cimento retrobturador MTA Angelus. Para análise da radiopacidade, os espécimes foram colocados em anéis metálicos medindo 10x1 mm, dispostos sobre um filme oclusal com uma escala de alumínio. O software Digora 1.51 foi utilizado para avaliar as imagens digitalizadas e determinar a densidade radiográfica. O tempo de presa foi realizado de acordo com as especificações da American Society for Testing and Materials C266-08 standard specifications, mas os espécimes foram feitos de acordo com a International Organization for Standardization 6876: 2001. O escoamento foi realizado de acordo com as especificações ANSI/ADA N0 57/2000. Trinta dentes acrílicos foram preenchidos com cimentos obturadores e vinte dentes de acrílico (com cavidade retrógrada) foram preenchidos com cimentos retro-obturadores e imersos em água ultrapura para mensuração do pH e liberação de íons cálcio (espectrofotômetro de absorção atômica) no período de 1, 3, 24, 72, 168 e 360 horas. Para o teste de solubilidade, foram escaneados 50 dentes acrílicos e digitalizados duas vezes pelo Micro-CT, antes e após a imersão em água ultrapura nos períodos de 168, 360 e 720 horas. As imagens foram reconstruídas e o volume (mm3) das amostras foi obtido usando o software CTan (CTan v1.11.10.0, SkyScan). Os efeitos celulares in vitro foram analisados nas concentrações de 100, 50, 10, 5, 1 mg/mL e 0 mg / mLgrupo controle negativo e registados nos períodos de 24, 48 e 72 horas através do ensaio de redução de MTT. Os resultados foram analisados estatisticamente pelos testes ANOVA, Tukey, Kruskal-Wallis e Dunn (p < 0.05). Todos os valores de radiopacidade estavam de acordo com a norma ISO 6876/2001, sendo o AH Plus (7.86 mm Al) o mais radiopaco seguido dos demais cimentos; Totalfill BC Sealer (4.84 mm Al), MTA Filapex (3.41 mm Al), Totalfill BC RRM (6,8 mm Al), MTA Angelus (6,7 mm Al). Os valores obtidos para o tempo de presa inicial e final foram respectivamente, AH Plus (8 e 15 horas), Totalfill BC Sealer (11 e 24 horas), MTA Filapex (13 e 26 horas), Totalfill BC RRM (3 horas e 22 horas) e MTA Angelus (10 e 120 minutos). Na análise de escoamento os cimentos se comportaram da seguinte forma: AH Plus (33 mm), MTA Filapex (47 mm), Totalfill BC Sealer (41,5 mm), Totalfill BC RRM (33,5 mm), e MTA Angelus (17,5 mm) (p < 0.05). A análise do pH mostrou que o cimento AH Plus de um modo geral, foi o que apresentou os menores valores, seguido do Totalfill BC RRM, MTA Angelus, MTA Filapex e Totalfill BC Sealer. A maior liberação de Ca2+ do AH Plus foi no período de 1 hora (1.38 mg/L), MTA Filapex foi em 360 horas (3.81 mg/L), Totalfill BC Sealer 360 horas (6.77 mg/L), Totalfill BC RRM 360 horas (3.81 mg/L) e MTA Angelus em 1 hora (1.38 mg/L). Todos os cimentos apresentaram solubilidade menor que 3% em todos os períodos, como recomendado pela ISO 6876/2001. Entretanto, os valores de solubilidade do MTA Fillapex excedeu mais que 5% em todos os períodos. Com relação à citotoxicidade, todos os cimentos mostraram-se tóxicos na concentração de 100 mg/mL, porém o Totalfill BC Sealer e Totalfill BC RRM apresentaram melhor resultado de viabilidade celular comparado aos demais cimentos testados. Concluiu-se que os cimentos de obturação e retro-obturação cumpriram os requisitos de radiopacidade, tempo de presa, escomento, pH, liberação de íons cálcio, solubilidade e citotoxicidade. Com exceção do MTA Fillapex que não cumpriu somente o requisito de solubilidade. Dos cimentos obturadores, o que melhor se portou foi o Totalfill BC Sealer, apresentando maior pH e liberação de íons cálcio e menor citotoxicidade. Dentre os cimentos retro-obturadores, Totalfill BC RRM foi o que melhor se destacou, mantendo seu pH elevado, possuindo maior liberação de Ca2+ e menor citotoxicidade

Estudo da anatomia radicular de segundos molares superiores por meio da Microtomografia Computadorizada

O objetivo deste estudo foi avaliar qualitativa e quantitativamente a anatomia do sistema de canais radiculares de segundos molares superiores por meio de microtomografia computadorizada. Cem dentes foram escaneados no micrótomografo (SkyScan 1174) utilizando uma resolução de 19,7 &#x3BC;m e reconstruídos para análises bidimensionais dos número de canais principais e ramificações, diâmetro maior (V-P) e menor (M-D) a 1, 2, 3, 4 e 5mm do forame apical e área (mm2) das raízes mésio-vestibular, disto-vestibular e palatina. Após a reconstrução tridimensional das amostras escaneadas a classificação do sistema de canais radiculares foi realizada de acordo com Vertucci e os tipos adicionais. Os resultados evidenciaram que nos 2mm apicais iniciais a raiz mésio-vestibular mostrou uma frequência maior do número de canais. O diâmetro maior (V-P) das raízes avaliadas aumentou gradualmente a cada milímetro no sentido ápico-cervical, o diâmetro menor (M-D) das raízes avaliadas diminuiu no segundo milímetro apical, voltando a aumentar a partir deste, a cada milímetro avaliado. A análise tridimensional revelou uma equivalência de dados com relação a classificação de Vertucci, principalmente na raiz palatina e disto-vestibular 98% e em menor escala a raiz mésio-vestibular com 64%. Dentre os tipos de classificações adicionais foram encontrados no presente estudo, 18% dessas classificações para as raízes mésio-vestibulares, 2% para as raízes disto-vestibulares e 1% para a raiz palatina. Este estudo registrou também novos tipos de anatomia, que não se enquadraram nas classificações de Vertucci e nas classificações adicionais dos outros autores: 18% das raízes mésio-vestibulares e 1% da raiz palatina. O presente estudo confirmou por meio do microCT, a alta incidência de canais mésio-palatinos e grande quantidad de ramificações nas raízes mésio-vestibulares nos segundos molares superiores.The aim of this study was to evaluate qualitatively and quantitatively the anatomy of the root canal system of maxillary second molars using computerized microtomography.One hundred samples were scanned at microCT (SkyScan 1174) using a resolution of 19.7 &#x3BC;m and reconstructed in two-dimensional slices to determine the number of main canals and branches, root canal diameter (B-P) and lower diameter (M-D) direction at 1, 2, 3, 4 and 5mm from the apical foramen. Also, the area (mm2) of the mesiobuccal, distobuccal and palatal roots was analyzed. The classification of the root canal system was performed according to Vertucci and additional authors classifications. The results showed that at the apical third, the mesiobuccal root showed a higher frequency of root canals and ramifications. In overall, the bucco-palatal diameter (B-P) and mesio-distal diameter (M-D) gradually increased from the apical to the cervical third. Threedimensional analysis revealed that 98% of disto-buccal and palatal canals fits in the Vertuccis classification. In the mesiobuccal canal 64% of the anatomies could be described by the Vertucci classification. Other authors classifications were found in 18% of mesiobuccal roots, 2% on distobuccal roots and 1% on palatal roots. This study found new types of root canal anatomies that were not previously described, mainly, in the mesiobuccal and palatal roots (19%). It can be concluded that the mesial buccal roots in maxillary second molars show a higher complexity in comparison to the distobuccal and palatal root