Push-out bond strength of mineral trioxide aggregate with addition of titanium dioxide, silver, and silicon dioxide nanoparticles: An in vitro comparative study.

Background: The ultimate goal of endodontic therapy is to eliminate all microorganisms present inside root canal and thereby sealing all the possible communicating pathways between pulpal and periradicular tissues, which prevents all the factors that cause recontamination and reinfection of the root canal system. If endodontic treatment fails, next approach is surgical endodontics. Bioceramics are recently introduced materials specifically designed for their potential use in medical field and dentistry. Aim: To evaluate and compare the push-out bond strength of mineral trioxide aggregate (MTA) by adding titanium dioxide (TiO2), silver, and silicon dioxide nanoparticles. Materials and Methods: Totally, 60 single-rooted human teeth were used. Middle third of the root was sectioned to obtain 2-mm thick root section. Acrylic was adapted to the section to obtain disks of 5 mm diameter and 2 mm thickness. Canal was prepared by GG Drill. Samples were divided into four groups of 15 each (n = 15): • Group I (control): MTA • Group II: MTA + TiO2 nanoparticles. • Group III: MTA + silver nanoparticles. • Group IV: MTA + silicon dioxide nanoparticles. The cement mixture was compacted into the canal. Samples were subjected to push-out bond strength using universal testing machine. Statistical Analysis Used: The data were analyzed statistically by analysis of variance and post hoc comparison by Tukey's t-test. Results: The highest push-out bond strength was shown by Group II (MTA with TiO2 nanoparticles), followed by Group III (MTA with silver nanoparticles) and Group I (MTA control group). The lowest push-out bond strength was shown by Group III (MTA with silicon dioxide nanoparticles). Conclusions: TiO2 and silver nanoparticles when added into MTA lead to an increase in push-out bond strength of MTA.

Green Synthesis of Nanomaterials Using Plant Extract: A Review.

For the last two decades, extensive research is conducted on metal and metal oxide nanoparticles and their application in the field of medical, cosmetics, catalysts, packaging, photonics, agriculture and electronics. However, these nanoparticles show toxicity to the environmental, human and animal health. The toxicity effects of nanoparticles are mainly due to their size, which can easily pass through physiological barriers and also due to the synthesis procedure. The toxicity due to their size cannot be avoided, but toxicity due to the synthesis process can be nullified by adopting the biosynthesis process. Bacteria, fungus, fish scales, plant extracts and algae are used to synthesize metal and metal- oxide nanoparticles such as silver, gold, iron-oxide, zinc-oxide, zirconia, etc. For the last few years, researchers have been working on synthesis methods of plant extracts to produce stable, cost-effective and economical nanoparticles. In this review, we focus on the biosynthesis of nanoparticles using different parts of plant extracts. The review contains a summary of selected papers from 2018-20 with a detailed description of the process of synthesis, mechanism, characterization and their application in various fields of biosynthesized metal and metal oxide nanoparticles.