Physicochemical, antimicrobial, and biological properties of White-MTAFlow.

OBJECTIVES: To evaluate a new material containing tantalum oxide as an alternative radiopacifier, and a water-based gel for hydration, in comparison with two calcium silicate-based cement: ProRoot MTA and Biodentine. MATERIALS AND METHODS: ProRoot MTA (Dentsply), Biodentine (Septodont), and a new hydraulic calcium silicate cement White-MTAFlow (Ultradent) (in 'thin' consistency) were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). The interaction with dentin was also assessed using SEM and EDS. Physical and chemical properties radiopacity, setting time, linear flow, volumetric central filling, and lateral flow, pH, and volume change were investigated together with the color luminosity (L) and color change (ΔE). The agar diffusion and direct contact antimicrobial activity, and methylthiazolyldiphenyl-tetrazolium-bromide (MTT) cytotoxicity using human fibroblast cells were also evaluated. Data were statistically analyzed at a 5% significance level. RESULTS: All materials were composed of tricalcium and dicalcium silicate but had different radiopacifiers, and calcium hydroxide (portlandite) deposition was detected in XRD analysis. White-MTAFlow exhibited radiopacity values in accordance with ISO standard, and the longest setting time. The water-based gel provided the highest linear flow, a comparable cavity central filling, and the highest groove-lateral flow in the volumetric flow analysis. White-MTAFlow exhibited an alkalinity reduction, and Biodentine, a progressive increase of pH values after 28 days. However, similar volume loss for White-MTAFlow was assessed in comparison to Biodentine after the 28-day immersion. White-MTAFlow showed the highest L value (91.5), and ProRoot MTA the lowest (78.1) due to dentin staining caused by bismuth migration. None of the materials exhibited inhibition halos against the tested bacteria, and similar turbidity values were obtained after 48 h in direct contact with E. faecalis, indicating an upregulation to bacterial growth. White-MTAFlow showed MTT cytocompatibility similarly to the control group. CONCLUSIONS: White-MTAFlow in 'thin' consistency presents comparable physicochemical, biological, and antimicrobial properties to ProRoot MTA and Biodentine, and does not cause color alteration in dentin. CLINICAL RELEVANCE: White-MTAFlow is a suitable material for use as reparative endodontic cement. Further studies considering its biocompatibility are necessary.

Bioactive molecule optimized for biofilm reduction related to childhood caries.

Aim: To evaluate antimicrobial activity of a new nitrochalcone (NC-E08) against Candida albicans and Streptococcus mutans, and its toxicity. Materials & methods: Minimum inhibitory concentration (MIC) and minimum bactericidal concentration/minimum fungicidal concentration (MFC) were determined against C. albicans and S. mutans, as well as antibiofilm potential and toxicity (human gingival fibroblast and Galleria mellonella). Infection and treatment were performed in G. mellonella. Results & conclusion: NC-E08 showed antimicrobial activity in C. albicans (MIC: 0.054 mM) and S. mutans (MIC: 0.013 mM); 10xMIC treatment reduced 4.0 log10 biofilms for both strains and there was a reduction in survival of mixed biofilms of C. albicans and S. mutans (6.0 and 4.0 log10, respectively). NC-E08 showed no cytotoxicity in human gingival fibroblast cells and G. mellonella. NC-E08 after larval infection protected them 90% (p < 0.05). Thus, is a promising one for the prevention and treatment of S. mutans and C. albicans infections.