Evaluation of the Antibacterial and Antifungal Effects of ProRoot MTA and Nano-fast Cement: An In Vitro Study.

AIM: One of the most vital characteristics of an ideal root filling material is the capability to inhibit the growth of the microorganisms. Mineral trioxide aggregate (MTA) is one of the most used root repair materials, with approved antibacterial effect. A newly introduced root repair material is nano-fast cement (NFC) which should be investigated. The antibacterial and antifungal activities of NFC were evaluated in the present study. MATERIALS AND METHODS: Enterococcus faecalis (PTCC 1394), Escherichia coli (ATTC 15224), and Candida albicans (PTCC 5027) were employed for the antimicrobial assessment. The following were the steps used to conduct the agar diffusion test (ADT): six agar plates were used. 0.5 McFarland concentration of each strain was cultured on two plates by a sterile cotton-tipped swab. Three holes with 5mm diameter were created on each plate. Freshly mixed cement was placed in the holes of the related plate. After two hours, the plates were incubated at 37°C for 24 hours. Then, the diameter of the growth inhibition zones were measured, and the mean values were used for the analysis. Direct contact test (DCT) was done by using the following steps: Freshly mixed materials were placed in the 96-well microtiter plate. 10 µL of each bacterial suspension was added to the tested cement. After one-hour incubation at 37°C, 245 µL of BHI broth was added to each well, and the plate was vortexed for 2 minutes. About 15 µL of this bacterial suspension was added to a new well which contained 215 µL of fresh medium. The kinetics of the bacterial outgrowth were measured by the microplate spectrophotometer hourly for 12 hours. RESULTS: No significant differences were observed between the diameters of the growth inhibition zones of MTA and NFC groups in ADT. In DCT, the MTA inhibits E. coli more effectively than NFC (p value < 0.001). Both cements had the same inhibitory effect on E. faecalis and C. albicans. CONCLUSION: The MTA and NFC are almost equally effective against the tested microorganisms. CLINICAL SIGNIFICANCE: The antibacterial characteristic of any dental material is an important matter. As well, the antibacterial efficacy of the NFC should be evaluated.

Cytotoxic Effect of Nano Fast Cement and ProRoot Mineral Trioxide Aggregate on L-929 Fibroblast Cells: an in vitro Study.

Statement of the Problem: Endodontic materials that are placed in direct contact with living tissues should be biocompatible. The cytotoxicity of Nano Fast Cement (NFC) compared to ProRoot Mineral Trioxide Aggregate (ProRoot MTA) must be evaluated. Purpose: This In vitro study aimed to assess the cytotoxic effects of NFC in comparison to ProRoot MTA on L-929 mouse fibroblast cells. Materials and Method: In this animal study, L-929 mouse fibroblast cells were grown in Dulbecco's Modified Eagle's medium (DMEM) supplemented with 10% fetal bovine serum (FBS) in an atmosphere of 5% co2/95% air at 37 C̊. A total of 104 cells from the fourth collection were plated in each well of a 96-well micro-titer plate. Materials were mixed according to the manufacturer's instruction and placed into the related plastic molds with 5 mm diameter and 3 mm height. After 24 hours and a complete setting, the extracts of the tested materials were produced at six different concentrations and placed in the related wells. Cells in DMEM served as the negative control group. DMEM alone was used as the positive control group. Methyl-thiazoltetrazolium (MTT) colorimetric assay was conducted after 24, 48, and 72 hours. The absorbance values were measured by ELISA plate reader at 540 nm wavelength. Three-way analysis of variance, post-hoc Tukey, LSD, and independent t-test were used for the statistical analyses using SPSS software, version 16.0. Results: There was no statically significant difference between MTA and NFC in cell viability values at different concentrations and different time intervals (p= 0.649). Viability values were significantly decreased after 72 hours, but there was no significant difference between the first and second MTT assays (p= 0.987). Cytotoxicity significantly increased at concentrations higher than 6.25 µÉ¡/ml. Conclusion: Cytotoxicity depends on time, concentration, and cement composition. There was no statistically significant difference between NFC and MTA concerning their cytotoxic effects on L-929 mouse fibroblast cells.

Postendodontic Pain after Pulpotomy or Root Canal Treatment in Mature Teeth with Carious Pulp Exposure: A Multicenter Randomized Controlled Trial.

This equivalence, randomized, clinical trial aimed to compare the postoperative pain of root canal therapy (RCT) with pulpotomy with mineral trioxide aggregate (PMTA) or calcium-enriched mixture (PCEM) in permanent mature teeth. In seven academic centers, 550 cariously exposed pulps were included and randomly allocated into PMTA (n = 188), PCEM (n = 194), or RCT (n = 168) arms. Preoperative "Pain Intensity" (PI) on Numerical Rating Scale and postoperative PIs until day 7 were recorded. Patients' demographic and pre-/intra-/postoperative factors/conditions were recorded/analysed. The arms were homogeneous in terms of demographics. The mean preoperative PIs were similar (P=0.998), the mean sum PIs recorded during 10 postoperative intervals were comparable (P=0.939), and the trend/changes in pain relief were parallel (P=0.821) in all study arms. The incidences of preoperative moderate-severe pain in RCT, PMTA, and PCEM arms were 56.5%, 55.7%, and 56.7%, which after 24 hours considerably decreased to 13.1%, 10.6%, and 12.9%, respectively (P=0.578). The time span of endodontic procedures was statistically different; RCT = 69.73, PMTA = 35.37, and PCEM = 33.62 minutes (P < 0.001). Patients with greater preoperative pain, symptomatic apical periodontitis, or presence of PDL widening suffered more pain (P=0.002, 0.035, and 0.023, resp.); however, other pre-/intra-/postoperative factors/conditions were comparable. Pulpotomy with MTA/CEM and RCT demonstrate comparable and effective postoperative pain relief.