AimTo analyse the cytotoxicity, colour change and radiopacity of MTA Flow (MTA), UltraCal XS (UC) and Bio‐C Temp (BT).MethodologyHuman dental pulp cells (hDPCs) stimulated with lipopolysaccharide (LPS) were placed in contact with several dilutions of culture media previously exposed to the experimental materials and tested for cell viability using MTT. Bovine teeth were prepared to simulate an open apex and to mimic extensive crown fracture. The roots were filled with a mixture of agar and blood, and the materials placed over this mixture. The control group consisted of teeth filled only with agar and blood. Colour assessment analyses were performed before and immediately after material insertion and repeated at 30, 45 and 60 days using a spectrophotometer. The total colour change (ΔEab, ΔE00 and whiteness index (WI)) was calculated based on the CIELAB colour space. Digital radiographs were acquired for radiopacity analysis. Cell viability was analysed by one‐way anova, whilst differences in colour parameters (ΔEab, ΔE00 and WI) were assessed by two‐way repeated measures anova (α = 0.05). Tukey's test was used to compare the experimental groups, and Dunnett’s test was used to compare the experimental groups with the control group.ResultsMTA, UC and BT had similar cell viability to that of the control group (DMEM) (P > 0.05), except for the BT group at the 1 : 1 and 1 : 2 dilutions, which had significantly lower viability (P < 0.001). All materials were associated with discoloration values greater than what is considered to be the acceptable threshold, and BT resulted in less or similar tooth colour change than MTA and UC, respectively. Decreasing radiopacity over time was observed only in the MTA group (P = 0.007). Lower values of radiopacity were found in the BT group compared with the UC and MTA groups (P < 0.001).ConclusionsThe new bioceramic material (BT) had acceptable cell viability, similar to that of MTA and UC at the highest dilutions, and BT resulted in less tooth colour change than MTA and UC. Despite its lower radiopacity, BT was identified radiographically.

Aim To analyse the discolouration, radiopacity, pH and calcium ion release of Biodentine (BD), Bio‐C repair (BCR) and Bio‐C temp (BCT), as well as their biological effects on human dental pulp cells (hDPCs). Methodology Sixty‐four extracted bovine incisors were prepared to simulate crown fractures with pulp exposure and open root apex. The roots were filled using a mixture of agar and blood (control), and BD, BCR or BCT were placed over this mixture. Colour assessment analyses of the samples were performed before and immediately after material insertion and repeated at 30 and 90 days, using a spectrophotometer. The colour change of each specimen was evaluated at the crown and calculated based on the CIELab colour space. Digital radiographs were acquired for radiopacity analysis. hDPCs were placed in contact with different dilutions of culture media previously exposed to such materials and tested for cell viability using the MTT assay. The pH and calcium ion release of all materials were measured after 24 h; the data were assessed using one‐way analysis of variance (ANOVA). Cell viability was analysed by two‐way ANOVA. Differences in colour parameters and wound‐healing data were assessed by two‐way repeated measures ANOVA (α = 0.05). Tukey's and Dunnett's tests were used to compare the experimental groups with the control group. Results BCR had grater radiopacity and smaller colour alteration (ΔEab/ΔE00) than the other materials tested (p < .005; p < .001). No significant differences in pH were found amongst the tested materials (p > .05). BCT was associated with the largest release of calcium ions (p < .0001). BD had cell viability similar to that of the control at the lowest dilutions, and BCR was similar to that of the control, regardless of the dilution tested (p > .05). BCT had a lower percentage of viability than that of the control at all tested dilutions (p < .0001). Cell migration rates in BD and BCR were similar to those in the control group after 24 h and 48 h (p > .05), whilst BCT had larger voids than the control in both periods (p < .0001). Conclusions BCR, BCT and BD were associated with tooth discolouration. BCR had the lowest staining values, the highest radiopacity and viability greater than 80% hDPCs.

Objectives This study aimed to synthesize nanocrystals (NCs) of zinc oxide (ZnO) and calcium ion (Ca 2+ )-doped ZnO with different percentages of calcium oxide (CaO), to evaluate cytotoxicity and to assess the effects of the most promising NCs on cytotoxicity depending on lipopolysaccharide (LPS) stimulation. Materials and Methods Nanomaterials were synthesized (ZnO and ZnO:xCa, x = 0.7; 1.0; 5.0; 9.0) and characterized using X-ray diffractometry, scanning electron microscopy, and methylene blue degradation. SAOS-2 and RAW 264.7 were treated with NCs, and evaluated for viability using the MTT assay. NCs with lower cytotoxicity were maintained in contact with LPS-stimulated (+LPS) and nonstimulated (−LPS) human dental pulp cells (hDPCs). Cell viability, nitric oxide (NO), and reactive oxygen species (ROS) production were evaluated. Cells kept in culture medium or LPS served as negative and positive controls, respectively. One-way analysis of variance and the Dunnett test (α = 0.05) were used for statistical testing. Results ZnO:0.7Ca and ZnO:1.0Ca at 10 µg/mL were not cytotoxic to SAOS-2 and RAW 264.7. +LPS and −LPS hDPCs treated with ZnO, ZnO:0.7Ca, and ZnO:1.0Ca presented similar NO production to negative control ( p > 0.05) and lower production compared to positive control ( p < 0.05). All NCs showed reduced ROS production compared with the positive control group both in +LPS and −LPS cells ( p < 0.05). Conclusions NCs were successfully synthesized. ZnO, ZnO:0.7Ca and ZnO:1.0Ca presented the highest percentages of cell viability, decreased ROS and NO production in +LPS cells, and maintenance of NO production at basal levels.

Aim To evaluate the in vitro cytotoxicity and cytokine release of three fresh root canal sealers and to determine the type of cell death they induce. Methodology The sealers tested were Sealer 26 (S26), AH Plus (AHP), and Endosequence BC Sealer (END). Fresh sealers were cultivated in contact with monocytes and polymorphonuclears (PMNs) obtained from the peripheral blood of humans. Cell viability, apoptosis and necrosis were analysed at 4 h (PMNs) or 24 h (monocytes) using Annexin‐V and propidium iodide in a cytometer. The supernatants were used to quantify Interleukin (IL)‐4, IL‐6, IL‐10, IL‐12 and tumour necrosis factor‐α (TNF‐α) in monocytes and IL‐8 in PMNs by ELISA. One‐way ANOVA and the Tukey post‐test were used to compare data for cytotoxicity, and the multiple T‐test was used to determine the differences between sealers in the release of cytokines that were statistically significant. Results After 4 h of treatment, S26 was associated with greater cell viability than the other sealers (P < 0.05) in the PMN culture and had similar values of necrosis as END (P > 0.05). After 24 h of treatment, AHP and END had greater monocyte cell viability than S26 (P < 0.05), which had more necrosis (P < 0.05). END had the lowest levels of IL‐12 compared to the other sealers (P < 0.05) and higher levels of IL‐6 compared to S26 (P < 0.05). The tested sealers did not differ in the release of IL‐8, IL‐10, TNF‐α and IL‐4 (P > 0.05). Conclusions The effect of toxic agents released varied depending on the cell type studied. The composition of the sealers appeared to alter the form of self‐regulation in the production of these cytokines by cells.

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