Abstract This study assessed the physicochemical and antibiofilm properties of white mineral trioxide aggregate (MTA) associated with 1 or 2% of farnesol. Setting time was evaluated based on ISO 6876/2012. Radiopacity was evaluated by radiographic analysis. pH was assessed after time intervals of 1, 3, 7, 14, 21, and 28 days. Solubility (% mass loss) and volumetric change (by micro-CT) of the cements were evaluated after immersion in distilled water. The presence of voids inside the materials was assessed by using micro-CT. Antibiofilm activity against Enterococcus faecalis was evaluated by crystal violet assay and the modified direct contact test performed with biofilm previously formed on bovine root dentin for 14 days. Data were submitted to ANOVA/Tukey tests with 5% significance level. The incorporation of farnesol into MTA increased its setting time, but decreased its solubility at 30 days and its volumetric loss in all periods (p < 0.05). Radiopacity and solubility after 7 days were similar among the materials (p > 0.05). The association of farnesol showed the highest pH value after 1 and 3 days (p < 0.05). The association of farnesol with MTA promoted a decrease in the presence of voids, and increased the antimicrobial activity on biofilm biomass of E. faecalis (p < 0.05). In conclusion, the addition of farnesol can be suggested to improve the antimicrobial properties and the consistency of MTA. (MTA 2 68762012 6876 2012 6876/2012 analysis 21 % ( microCT micro CT micro-CT water microCT. CT. ANOVATukey ANOVA Tukey 5 level p 0.05. 005 0.05 . 0 05 0.05) E conclusion 6876201 687 201 6876/201 00 0.0 687620 68 20 6876/20 0. 68762 6 6876/2 6876/

Resumen Las diferencias en la proporción líquido/polvo pueden afectar las propiedades de los materiales a base de silicato de calcio. Este estudio evaluó la influencia de la proporción polvo/gel en las propiedades fisicoquímicas del cemento NeoMTA Plus. El tiempo de fraguado (minutos), la fluidez (mm y mm²), el pH (en diferentes períodos), la radiopacidad (mmAl) y la solubilidad (% de pérdida de masa) fueron evaluados utilizando las consistencias para el material de reparación radicular (NMTAP-RP; 3 cucharadas de polvo/2 gotas de gel) y para cemento sellador del conducto radicular (NMTAP-SE; 3 cucharadas de polvo/3 gotas de gel), en comparación con el cemento Biodentine (BIO) y el cemento TotalFill BC (TFBC). El análisis estadístico se realizó utilizando las pruebas ANOVA y Tukey unidireccionales (α=0.05). BIO tuvo el tiempo de fraguado más corto, seguido de NMTAP-RP y NMTAP-SE. TFBC mostró el mayor tiempo de fraguado y radiopacidad. BIO, NMTAP-RP y NMTAP-SE tuvieron una radiopacidad similar. Todos los materiales promovieron un pH alcalino. NMTAP-RP/ SE tuvieron una solubilidad menor que BIO y TFBC. Con respecto a la fluidez, TFBC tuvo los valores más altos, seguido de NMTAP-SE y NMTAP-RP. BIO tuvo la fluidez más baja. En conclusión, NMTAP en la relación polvo/gel mostró un pH alto y una baja solubilidad. El aumento en la proporción de polvo disminuyó el tiempo de fraguado y la fluidez. Estos hallazgos son importantes con respecto a su consistencia y tiempo de trabajo durante la aplicación clínica.

Abstract Differences in liquid-to-powder ratio can affect the properties of calcium silicate-based materials. This study assessed the influence of powder-to-gel ratio on physicochemical properties of NeoMTA Plus. Setting time (minutes), flow (mm and mm²), pH (at different periods), radiopacity (mm Al) and solubility (% mass loss) were evaluated using the consistencies for root repair material (NMTAP-RP; 3 scoops of powder to 2 drops of gel) and root canal sealer (NMTAP-SE; 3 scoops of powder to 3 drops of gel), in comparison to Biodentine cement (BIO) and TotalFill BC sealer (TFBC). Statistical analysis was performed using one-way ANOVA and Tukey tests (α=0.05). BIO had the shortest setting time, followed by NMTAP-RP and NMTAP-SE. TFBC showed the highest setting time and radiopacity. BIO, NMTAP-RP, and NMTAP-SE had similar radiopacity. All materials promoted an alkaline pH. NMTAP-RP/SE presented lower solubility than BIO and TFBC. Regarding the flow, TFBC had the highest values, followed by NMTAP-SE, and NMTAP-RP. BIO had the lowest flow. In conclusion, NMTAP in both powder-to-gel ratios showed high pH and low solubility. The increase in the powder ratio decreased the setting time and flow. These findings are important regarding the proper consistency and work time to clinical application.

Abstract Dental materials should be stable over time. This study investigated volumetric change of the root canal sealers AH Plus, Fill Canal, and Sealapex; and the root-end filling materials Biodentine, IRM, and MTA after different periods of immersion in distilled water. Resin models were manufactured with cavities 3 mm deep. The cavities were filled with the materials and scanned by microcomputed tomography after setting, and after 7 and 30 days immersed in distilled water. Percentages of volumetric changes after 7 and 30 days of immersion were compared by t-test. ANOVA/Tukey tests were used to compare endodontic materials (5% significance level). All root canal sealers had an increase in their volumetric change after 30 days. Among root-end filling materials, only IRM showed difference between the periods. Biodentine showed more volumetric changes than MTA, but both materials kept their volume from 7 to 30 days. In conclusion, the immersion period of endodontic materials may affect their stability.

Resumo O objetivo deste estudo foi avaliar propriedades físicas de cimentos endodônticos (AH Plus, MTA Fillapex e Endofill), por meio de testes convencionais e micro-CT. A estabilidade dimensional foi avaliada após imersão dos materiais em água destilada por 30 dias. A solubilidade e a alteração volumétrica dos materiais foram avaliadas após 7 e 30 dias de imersão em água destilada. A solubilidade foi avaliada por meio de perda de massa e a alteração volumétrica foi avaliada por micro-CT. A porosidade foi avaliada por microscopia após 7 dias de imersão em água destilada e por micro-CT após a presa e imersão em água destilada por 7 e 30 dias. A análise estatística foi realizada por meio dos testes ANOVA e Tukey, com nível de significância de 5%. MTA Fillapex apresentou a maior solubilidade (p<0,05), com valores acima das recomendações ISO/ADA. As alterações volumétricas e dimensionais foram maiores para MTA Fillapex, seguido por Endofill e AH Plus (p<0,05). MTA Fillapex e AH Plus não cumpriram os padrões ISO/ADA em relação à estabilidade dimensional. Uma maior porosidade total foi observada para MTA Fillapex (p <0,05). Endofill apresentou maior porosidade total que o AH Plus pela avaliação em microscopia (p<0,05), e ambos os cimentos foram semelhantes na avaliação por micro-CT (p>0,05). Em conclusão, MTA Fillapex apresentou maior solubilidade, alteração dimensional e volumétrica, além de maior porosidade em relação aos demais cimentos avaliados. As propriedades físicas avaliadas estão relacionadas, e os diferentes testes forneceram dados complementares. Micro-CT é um método valioso para avaliação das propriedades físicas dos materiais endodônticos.

Abstract The aim of this study was to evaluate physical properties of endodontic sealers (AH Plus, MTA Fillapex and Endofill), by conventional and micro-CT tests. Dimensional stability was evaluated after immersion of materials in distilled water for 30 days. Solubility and volumetric change were evaluated after 7 and 30 days of immersion in distilled water. Solubility was evaluated by means of mass loss and volumetric change was assessed by micro-CT. Porosity was evaluated under a microscope after 7 days of immersion in distilled water, and by using micro-CT after setting and immersion in distilled water for 7 and 30 days. Statistical analysis was performed by ANOVA and Tukey’s test with 5% significance level. MTA Fillapex presented the highest solubility (p<0.05), showing values above the ISO/ADA recommendations. MTA Fillapex presented higher volumetric and dimensional changes, followed by Endofill and AH Plus (p<0.05). Dimensional stability of the MTA Fillapex and AH Plus did not follow ISO/ADA standards. The highest total porosity was observed for MTA Fillapex (p<0.05). Endofill had higher total porosity than AH Plus according to microscope evaluation (p<0,05), and both sealers were similar in micro-CT assessment (p>0,05). In conclusion, MTA Fillapex presented higher solubility, dimensional and volumetric change besides porosity compared to the other evaluated sealers. The assessed physical properties of sealers are related, and the different tests provided complementary data. Micro-CT is a valuable method for assessment of physical properties of endodontic materials.

Resumo Este estudo avaliou as propriedades físico-químicas, citotoxicidade e bioatividade do MTA Angelus (MTA), cimento à base de silicato de cálcio (CSC) e CSC com 30% de óxido de itérbio (CSC/Yb2O3). O tempo de presa foi avaliado usando agulhas Gilmore. A resistência à compressão foi avaliada em uma máquina mecânica. A radiopacidade foi avaliada utilizando radiografias dos materiais e uma escala de alumínio. A solubilidade foi avaliada após imersão em água. A viabilidade celular foi avaliada por meio do ensaio MTT e coloração de vermelho neutro (NR), e a atividade de mineralização por meio da atividade da fosfatase alcalina e a coloração com Vermelho de Alizarina. Os dados foram submetidos aos testes ANOVA, Tukey e Bonferroni (5% de significância). O potencial bioativo foi avaliado por microscopia eletrônica de varredura. Os materiais apresentaram tempo de presa semelhante. O MTA mostrou menor resistência à compressão. MTA e CSC/Yb2O3 apresentaram radiopacidade semelhante. CSC/Yb2O3 apresentou menores valores de solubilidade. A viabilidade celular realizada pelos ensaios de MTT e NR não revelaram efeitos ctotóxicos em todas as diluições, exceto na diluição 1:1 no NR, o qual mostrou baixa viabilidade celular (p<0.05) em todos materiais testados quando comparado ao controle. A atividade de ALP em 1 e 7 dias foi similar ao controle (p>0.05). MTA e CSC tiveram significante aumento na atividade de ALP aos 3 dias quando comarados ao controle (p>0.05). Todos os materiais apresentaram grande produção de nódulos mineralizados quando comparados ao controle (P<0.05). A análise da SEM mostrou estruturas que sugerem a presença de depósitos de fosfato de cálcio na superfície dos materiais demonstrando bioatividade. O Yb2O3 mostrou ser um agente radiopacificador adequado em cimentos à base de silicato de cálcio uma vez que não afetou as propriedades físico-químicas e biológicas e ainda preservou o potencial bioativo desse material.

Abstract This study evaluated physicochemical properties, cytotoxicity and bioactivity of MTA Angelus (MTA), calcium silicate-based cement (CSC) and CSC with 30% Ytterbium oxide (CSC/Yb2O3). Setting time was evaluated using Gilmore needles. Compressive strength was evaluated in a mechanical machine. Radiopacity was evaluated using radiographs of materials and an aluminum scale. Solubility was evaluated after immersion in water. Cell viability was evaluated by means of MTT assay and neutral red staining, and the mineralization activity by using alkaline phosphatase activity and Alizarin Red staining. The data were submitted to ANOVA, Tukey and Bonferroni tests (5% significance). The bioactive potential was evaluated by scanning electron microscopy. The materials presented similar setting time. MTA showed the lowest compressive strength. MTA and CSC/Yb2O3 presented similar radiopacity. CSC/Yb2O3 showed low solubility. Saos-2 cell viability tests showed no cytotoxic effect, except to 1:1 dilution in NR assay which had lower cell viability when compared to the control. ALP at 1 and 7 days was similar to the control. MTA and CSC had greater ALP activity at 3 days when compared to control. All the materials present higher mineralized nodules when compared with the control. SEM analysis showed structures suggesting the presence of calcium phosphate on the surface of materials demonstrating bioactivity. Ytterbium oxide proved to be a properly radiopacifying agent for calcium silicate-based cement since it did not affected the physicochemical and biological properties besides preserving the bioactive potential of this material.

Abstract Objective: To evaluate the absorption/fluid uptake, solubility and porosity of White mineral trioxide aggregate (MTA) Angelus, Biodentine (BIO), and zinc oxide-eugenol (ZOE). Material and Methods: Solubility was evaluated after immersion in distilled water for 7 and 30 days. Porosity was evaluated using digital inverted microscope, scanning electron microscope (SEM) and micro-computed tomography (micro-CT). For the fluid uptake test, specimens were immersed in Hank's balanced salt solution (HBSS) for 1, 7, 14 and 28 days. Fluid absorption, solubility and porosity of the materials were measured after each period. Statistical evaluation was performed using one-way analysis of variance (ANOVA) and Tukey tests, with a significance level at 5%. Results: After 7 and 30 days, BIO showed the highest solubility (p<0.05). All methods demonstrated that MTA had total porosity higher than BIO and ZOE (p<0.05). Micro-CT analysis showed that MTA had the highest porosity at the initial period, after its setting time (p<0.05). After 7 and 30 days, ZOE had porosity lower than MTA and BIO (p<0.05). Absorption was similar among the materials (p>0.05), and higher fluid uptake and solubility were observed for MTA in the fluid uptake test (p<0.05). Conclusions: BIO had the highest solubility in the conventional test and MTA had higher porosity and fluid uptake. ZOE had lower values of solubility, porosity and fluid uptake. Solubility, porosity and fluid uptake are related, and the tests used provided complementary data.

Abstract Objective To evaluate solubility, dimensional stability, filling ability and volumetric change of root-end filling materials using conventional tests and new Micro-CT-based methods. Material and Methods Solubility (loss of mass) after 7 and 30 days, and dimensional stability (in mm) were evaluated in accordance with Carvalho-Junior, et al. 7 (2007). The filling ability and volumetric change (in mm3) were evaluated by Micro-CT (Bruker-MicroCT, Kontich, Belgium) using resin models with cavities 3 mm deep and 1 mm in diameter. The cavities were filled with materials to evaluate filling ability, and then scanned by Micro-CT. After 7 and 30 days immersed in distilled water, the filled cavities were scanned again to evaluate the volumetric change. MTA Angelus (MTA), Biodentine (BIO) and zinc oxide-eugenol cement (ZOE) were evaluated. Data were submitted to analysis of variance (ANOVA) and Tukey's test with 5% significance level. Results The results suggested correlated or complementary data between the proposed tests. At 7 days, BIO showed higher solubility and at 30 days, showed higher volumetric change in comparison with MTA (p<0.05). With regard to volumetric change, the tested materials were similar (p>0.05) at 7 days. At 30 days, they presented similar solubility. BIO and MTA showed higher dimensional stability than ZOE (p<0.05). ZOE and BIO showed higher filling ability (p<0.05). Conclusions ZOE presented a higher dimensional change, and BIO had greater solubility after 7 days. BIO presented filling ability and dimensional stability, but greater volumetric change than MTA after 30 days. Micro-CT can provide important data on the physicochemical properties of materials complementing conventional tests.

Resumo O objetivo deste estudo foi avaliar as propriedades físico-químicas e a resistência de união à dentina apical do cimento Biodentine em comparação ao MTA branco e cimento à base de óxido de zinco e eugenol (OZE). O tempo de presa e a radiopacidade foram avaliados de acordo com as especificações ISO 6876:2012. O tempo de presa final, a resistência à compressão e o pH também foram avaliados. A resistência de união dos materiais à dentina apical do canal radicular foi avaliada por meio do ensaio push-out. Dados foram analisados por ANOVA e teste complementar de Tukey-Krammer. Biodentine apresentou o menor tempo de presa inicial (16,2±1,48 min) e final (35,4±5,55 min). Os valores de radiopacidade do Biodentine (2,79±0,27 mmAl) não estão de acordo com as especificações ISO 6876:2012. Por outro lado, este material apresentou maior resistência à compressão após 21 dias (37,22±5,27 MPa) e maiores valores de adesão à dentina (11,2±2,16 MPa) em comparação ao MTA branco (27,68±3,56 MPa de resistência à compressão e 2,98±0,64 MPa de resistência de união) (p>0.05). Ambos os materiais produziram ambiente alcalino (aproximadamente 10) (p>0.05) em comparação ao OZE (pH 7). Pode-se concluir que o Biodentine demonstrou endurecimento mais rápido e apresentou maior resistência à compressão e resistência de união à dentina apical do que MTA e OZE.

Abstract The aim of this study was to evaluate the physicochemical properties and the apical dentin bond strength of the tricalcium silicate-based Biodentine in comparison to white MTA and zinc oxide eugenol-based cement (ZOE). Setting time and radiopacity were evaluated according to ISO 6876:2012 specification. Final setting time, compressive strength and pH were also assessed. Material’s bond strength to the apical root canal dentin was measured by the push-out assay. Data were analyzed by ANOVA and Tukey-Krammer post-hoc test. Biodentine presented the shortest initial (16.2±1.48 min) and final setting time (35.4±5.55 min). Radiopacity of Biodentine (2.79±0.27 mmAl) does not agree with ISO 6876:2012 specifications. On the other hand, Biodentine showed higher compressive strength after 21 days (37.22±5.27 MPa) and higher dentin bond strength (11.2±2.16 MPa) in comparison to white MTA (27.68±3.56 MPa for compressive strength and 2.98±0.64 MPa for bond strength) (p<0.05). Both MTA and Biodentine produced an alkaline environment (approximately pH 10) (p>0.05) compared to ZOE (pH 7). It may be concluded that Biodentine exhibited faster setting, higher long-term compressive strength and bond strength to the apical dentin than MTA and ZOE.

Resumo Mineral trióxido agregado (MTA) e cimento Portland (CP) são cimentos à base de silicato de cálcio. Eles apresentam propriedades físico-químicas, mecânica e biológicas semelhantes. A adição de óxido de zircônio (ZrO2) ao CP confere radiopacidade. Nanopartículas de prata (NPsAg) podem melhorar propriedades dos cimentos. O objetivo deste estudo foi avaliar o efeito da NPsAg nas propriedades físico-químicas, mecânicas e na atividade antibacteriana do MTA branco (WMTA) e CP associado ao ZrO2. Os seguintes materiais foram avaliados: WMTA; CP 70% + ZrO2 30%; ; WMTA + NPsAg; CP 70% + ZrO2 30% + NPsAg. Foram avaliados a radiopacidade, tempo de presa, pH, resistência à compressão e solubilidade. Para análise da radiopacidade foram tiradas radiografias ao lado de uma escala de alumínio (Al). Para avaliar a atividade antibacteriana, foi realizado o teste de contato direto sobre células planctônicas e biofilme de Enterococcus faecalis formado em dentina radicular bovina durante 14 dias. Os períodos experimentais foram 5 e 15 h. Os dados foram obtidos como UFC mL-1 e submetidos aos testes de ANOVA e Tukey (p<0,05). A adição de NPsAg ao WMTA elevou o pH, diminuiu a solubilidade e os tempos de presa inicial e final. A adição de NPsAg ao CP/ZrO2 manteve o pH, diminuiu a solubilidade, aumentou o tempo de presa e a resistência à compressão. A radiopacidade de todos os materiais foi maior do que 4 mmAl. A adição de NPsAg promoveu um aumento da atividade antibacteriana dos cimentos à base de silicato de cálcio e favoreceu as propriedades físico-químicas e mecânicas dos materiais.

Abstract Mineral trioxide aggregate (MTA) and Portland cement (PC) are calcium silicate cements. They have similar physicochemical, mechanical and biological properties. The addition of zirconium oxide (ZrO2) to PC provides radiopacity. Silver nanoparticles (AgNPs) may improve some properties of cements. The aim of this study was to evaluate the effect of AgNPs on physicochemical/mechanical properties and antibacterial activity of white MTA (WMTA) and PC associated with ZrO2. The following materials were evaluated: WMTA; PC 70% + ZrO2 30%; WMTA+ AgNPs; and PC 70% + ZrO2 30% + AgNPs. The study evaluated radiopacity, setting time, pH, compressive strength and solubility. For radiopacity analysis, radiographs were made alongside an aluminum (Al) step wedge. To evaluate the antibacterial activity, direct contact test was performed on planktonic cells and Enterococcus faecalis biofilm induced on bovine root dentin for 14 days. The experimental periods were 5 and 15 h. Data were obtained as CFU mL-1. The obtained data were submitted to ANOVA and Tukey tests (p<0.05). The addition of AgNPs to WMTA increased the pH, lowered the solubility and the initial and final setting times. The addition of AgNPs to PC/ZrO2 maintained the pH, lowered the solubility, and increased the setting time and compressive strength. The radiopacity of all materials was higher than 4 mmAl. The addition of AgNPs promoted an increase in antibacterial activity for calcium silicate cements and favored the physicochemical and mechanical properties of the materials.

ABSTRACT Objective Mineral Trioxide Aggregate (MTA) is a calcium silicate cement composed of Portland cement (PC) and bismuth oxide. Hydroxyapatite has been incorporated to enhance mechanical and biological properties of dental materials. This study evaluated physicochemical and mechanical properties and antibiofilm activity of MTA and PC associated with zirconium oxide (ZrO2) and hydroxyapatite nanoparticles (HAn). Material and Methods White MTA (Angelus, Brazil); PC (70%)+ZrO2 (30%); PC (60%)+ZrO2 (30%)+HAn (10%); PC (50%)+ZrO2 (30%)+HAn (20%) were evaluated. The pH was assessed by a digital pH-meter and solubility by mass loss. Setting time was evaluated by using Gilmore needles. Compressive strength was analyzed by mechanical test. Samples were radiographed alongside an aluminum step wedge to evaluate radiopacity. For the antibiofilm evaluation, materials were placed in direct contact with E. faecalis biofilm induced on dentine blocks. The number of colony-forming units (CFU mL-1) in the remaining biolfilm was evaluated. The results were submitted to ANOVA and the Tukey test, with 5% significance. Results There was no difference in pH levels of PC+ZrO2, PC+ZrO2+HAn (10%) and PC+ZrO2+HAn (20%) (p>0.05) and these cements presented higher pH levels than MTA (p<0.05). The highest solubility was observed in PC+ZrO2+HAn (10%) and PC+ZrO2+HAn (20%) (p<0.05). MTA had the shortest initial setting time (p<0.05). All the materials showed radiopacity higher than 3 mmAl. PC+ZrO2 and MTA had the highest compressive strength (p<0.05). Materials did not completely neutralize the bacterial biofilm, but the association with HAn provided greater bacterial reduction than MTA and PC+ZrO2 (p<0.05) after the post-manipulation period of 2 days. Conclusions The addition of HAn to PC associated with ZrO2 harmed the compressive strength and solubility. On the other hand, HAn did not change the pH and the initial setting time, but improved the radiopacity (HAn 10%), the final setting time and the E. faecalis antibiofilm activity of the cement.

Resumo O objetivo deste estudo foi avaliar a resistência de união de materiais retrobturadores. Quarenta fatias de 2 mm de espessura foram obtidas a partir de dentes unirradiculares humanos. Após o preparo do canal radicular usando uma broca cilíndrica de 1,5 mm de diâmetro, as paredes de dentina foram preparadas usando uma ponta de ultra-som diamantada (CVD T0F-2). As amostras foram divididas de acordo com os materiais (n=10): MTA Angelus (MTAA), MTA Sealer (MTAS, experimental), Sealer 26 (S26) e óxido de zinco e eugenol (ZOE). O teste de push-out foi realizado utilizando uma máquina de ensaios mecânicos (EMIC DL 2000) com velocidade de 1 mm/min. O tipo de falha foi avaliado em estereomicroscópio. Os resultados foram submetidos a ANOVA e teste de Tukey, com níveis de variância de 5%. MTAA (19,18 MPa), MTAS (19,13 MPa) e S26 (15,91 MPa) apresentaram os maiores valores de resistência de união (p<0,05). ZOE (9,50 MPa) apresentou os menores valores de resistência de união (p<0,05). A falha adesiva foi prevalente em todos os grupos, com exceção do ZOE, que apresentou falhas mistas. Concluiu-se que os materiais retrobturadores MTA Angelus, MTA Sealer e Sealer 26 apresentam maior resistência de união às paredes dentinárias que o óxido de zinco e eugenol após o preparo retrógrado.

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.

Mineral Trioxide Aggregate (MTA) is a calcium silicate-based material. New sealers have been developed based on calcium silicate as MTA Fillapex and MTA Plus. Objective The aim of this study was to evaluate biocompatibility and bioactivity of these two calcium silicate-based sealers in culture of human dental pulp cells (hDPCs). Material and Methods The cells were isolated from third molars extracted from a 16-year-old patient. Pulp tissue was sectioned into fragments with approximately 1 mm3 and kept in supplemented medium to obtain hDPCs adherent cultures. Cell characterization assays were performed to prove the osteogenic potential. The evaluated materials were: MTA Plus (MTAP); MTA Fillapex (MTAF) and FillCanal (FC). Biocompatibility was evaluated with MTT and Neutral Red (NR) assays, after hDPCs exposure for 24 h to different dilutions of each sealer extract (1:2, 1:3 and 1:4). Unexposed cells were the positive control (CT). Bioactivity was assessed by alkaline phosphatase (ALP) enzymatic assay in cells exposed for one and three days to sealer extracts (1:4 dilution). All data were analyzed by ANOVA and Tukey post-test (p≤0.05%). Results MTT and NR results showed suitable cell viability rates for MTAP at all dilutions (90-135%). Cells exposed to MTAF and FC (1:2 and 1:4 dilutions) showed significant low viability rate when compared to CT in MTT. The NR results demonstrated cell viability for all materials tested. In MTAP group, the cells ALP activity was similar to CT in one and three days of exposure to the material. MTAF and FC groups demonstrated a decrease in ALP activity when compared to CT at both periods of cell exposure. Conclusions The hDPCs were suitable for the evaluation of new endodontic materials in vitro. MTAP may be considered a promising material for endodontic treatments.