Investigation of the structure and compressive strength of a bioceramic root canal sealer reinforced with nanomaterials.

OBJECTIVES: A root canal sealer that can increase the resistance of endodontically treated teeth to compressive strength would be of great advantage. The purpose of this study is to use three different nanoparticles: multi-walled carbon nanotubes (MWCNTs), Titanium carbides (TC), and Boron nitrides (BN) into a bioceramic adhesive root canal sealer; BioRoot™ RCS, in an attempt to improve its structural and compressive strength properties. METHODS: Three composites of two weight fractions (1- and 2-wt.%) were produced by mixing each nanomaterial separately with a pre-weighed mass of Bioroot powder. The microstructural properties and compressive strength of the different hardened composites obtained were investigated. The composites have been characterized by X-ray Diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. Compression testing was performed. RESULTS: The 1-wt.% composites, Bioroot/MWCNTs, and Bioroot/TC, except for the one reinforced with BN, displayed a significant improvement in the compressive strength compared to pristine BioRoot™ RCS. The 2-wt.% composites showed no significant improvement in the compressive strength. CONCLUSION: The addition of 1-wt.% MWCNTs and TC nanomaterials can be considered in the future for enhancing the microstructure and compressive strength properties of pristine BioRoot™ RCS.

Effect of sintering temperature on the physiochemical properties, microstructure, and compressive strength of a bioceramic root canal sealer reinforced with multi-walled carbon nanotubes and titanium carbide.

AIM: Bioceramic root canal sealers like BioRoot RCS have received significant attention for use in endodontics. The addition of a nanophase material like multi-walled carbon nanotubes (MWCNTs) and titanium carbide (TC) to its matrix combined with pressureless sintering might have the potential for improved physiochemical, microstructure, and compressive strength properties. METHOD: ology: MWCNTs and TC nanomaterials were added at a percentage of 1 wt% to a definite weight of pristine BioRoot RCS. Two composites were prepared by ball milling followed by pressureless sintering in static nitrogen at temperatures 600 °C and 800 °C. The setting time, solubility, pH, compressive strength, and density were determined and compared to pristine BioRoot RCS. The microstructural properties of the composites were investigated by XRD, FTIR, Raman spectroscopy, and SEM. RESULTS: The final setting time before and after sintering at 600 °C of the composites was accelerated compared to Bioroot RCS (p = 0.016). The solubility of Bioroot/TC sintered at 600 °C was the lowest (p = 0.07) and its compressive strength was the highest among the sintered samples (p = 0.01). The incorporation of MWCNTs and TC had a significant increase in the compressive strength of Bioroot RCS (p < 0.05). CONCLUSION: The obtained results support the addition of nanomaterials to Bioroot RCS and the use of pressureless sintering.

Physiochemical properties of a bioceramic-based root canal sealer reinforced with multi-walled carbon nanotubes, titanium carbide and boron nitride biomaterials.

AIM: Bioceramic-containing root canal sealers are the most recently introduced sealers in endodontics. The present work reported experiments on a bioceramic-based root canal sealer with the objective of improving its physiochemical properties via reinforcement with each one of the three different nanomaterials: multi-walled carbon nanotubes (MWCNTS), titanium carbide (TC) or boron nitride (BN) in two weight percentages (1 wt% and 2 wt%). METHODOLOGY: Each nanomaterial was added to a definite weight of BioRoot root canal sealer (BioRoot™ RCS, Septodont, Saint-Maur-des-Fossés, France). Three composite groups of each weight percentage were prepared for evaluation: BioRoot/MWCNTS, BioRoot/TC and BioRoot/BN. The initial and final setting times, solubility, elution and pH values of the freshly-mixed and set samples were evaluated and compared to pristine BioRoot™ RCS. Setting times were evaluated using Gilmore needles. Solubility and elution were determined after immersion in water for 24 h. Scanning electron microscopy was used to examine the microstructure of the composite materials. RESULTS: The 1-wt. % composites possessed significantly shorter initial and final setting times compared with the pristine BioRoot™ RCS (p < 0.05). The 2-wt.% composites exhibited longer initial setting times but significantly shorter final setting times than BioRoot RCS (p < 0.05). Most of the composites had relatively lower solubility and elution profiles, with BioRoot/1-wt.% TC and BioRoot/1-wt.% BN being the lowest (p < 0.05). BioRoot™ RCS and all composites exhibited an alkaline pH profile over a period of 4 weeks and a significantly higher alkaline pH (p < 0.05) was recorded for BioRoot/1-wt.% and Bioroot/2-wt.% TC. CONCLUSIONS: A bioceramic-containing root canal sealer (BioRootTM RCS) with a shorter setting time, an alkaline pH profile, and a relatively lower solubility may be developed by incorporation of nanomaterials.