The demands for dental materials continue to grow, driven by the desire to reach a better performance than currently achieved by the available materials. In the dental restorative ceramic field, the structures evolved from the metal-ceramic systems to highly translucent multilayered zirconia, aiming not only for tailored mechanical properties but also for the aesthetics to mimic natural teeth. Ceramics are widely used in prosthetic dentistry due to their attractive clinical properties, including high strength, biocompatibility, chemical stability, and a good combination of optical properties. Metal-ceramics type has always been the golden standard of dental reconstruction. However, this system lacks aesthetic aspects. For this reason, efforts are made to develop materials that met both the mechanical features necessary for the safe performance of the restoration as well as the aesthetic aspects, aiming for a beautiful smile. In this field, glass and high-strength core ceramics have been highly investigated for applications in dental restoration due to their excellent combination of mechanical properties and translucency. However, since these are recent materials when compared with the metal-ceramic system, many studies are still required to guarantee the quality and longevity of these systems. Therefore, a background on available dental materials properties is a starting point to provoke a discussion on the development of potential alternatives to rehabilitate lost hard and soft tissue structures with ceramic-based tooth and implant-supported reconstructions. This review aims to bring the most recent materials research of the two major categories of ceramic restorations: ceramic-metal system and all-ceramic restorations. The practical aspects are herein presented regarding the evolution and development of materials, technologies applications, strength, color, and aesthetics. A trend was observed to use high-strength core ceramics type due to their ability to be manufactured by CAD/CAM technology. In addition, the impacts of COVID-19 on the market of dental restorative ceramics are presented.
Methylene blue (MB), a widely used industrial dye, is a persistent pollutant with documented toxicity to aquatic organisms and potential health risks to humans, even at ultra-trace levels. Conventional monitoring techniques such as UV–Vis spectroscopy and fluorescence emission suffer from limited sensitivity, typically failing to detect MB below ~10−7 M. In this study, we introduce a surface-enhanced Raman spectroscopy (SERS) platform based on silver nanowire (AgNW) substrates that enables MB detection over an unprecedented dynamic range—from 1.5 × 10−4 M down to 1.5 × 10−16 M. Raman mapping confirmed the presence of individual signal hot spots at the lowest concentration, consistent with the theoretical number of analyte molecules in the probed area, thereby demonstrating near-single-molecule detection capability. The calculated enhancement factors reached up to 1.90 × 1012, among the highest reported for SERS-based detection platforms. A semi-quantitative calibration curve was established spanning twelve orders of magnitude, and this platform was successfully applied to monitor MB degradation during two advanced oxidation processes (AOPs): TiO2 nanotube-mediated photocatalysis under UV irradiation and atmospheric-pressure dielectric barrier discharge (DBD) plasma treatment. While UV–Vis and fluorescence techniques rapidly lost sensitivity during the degradation process, the SERS platform continued to detect the characteristic MB Raman peak at ~1626 cm−1 throughout the entire treatment duration. These persistent SERS signals revealed the presence of residual MB or partially degraded aromatic intermediates that remained undetectable by conventional optical methods. The results underscore the ability of AgNW-based SERS to provide ultra-sensitive, molecular-level insights into pollutant transformation pathways, enabling time-resolved tracking of degradation kinetics and validating treatment efficiency. This work highlights the importance of integrating SERS with AOPs as a powerful complementary strategy for advanced environmental monitoring and water purification technologies. By delivering an ultra-sensitive, low-cost sensor (<USD 0.16 per test) and promoting reagent-free treatment methods, this study directly advances SDG 6 (Clean Water and Sanitation) and SDG 12 (Responsible Consumption and Production).
6 February 2025 in Journal of the Mechanical Behavior of Biomedical Materials
Chronic wounds may develop when there is a delay or disturbance in one of the stages of the healing process, presenting challenging financial, clinical, and quality‐of‐life costs. Therefore, continuous efforts have been made to develop dressings that optimise wound healing. In recent years, nanotechnology has revolutionised wound care, enabling the development of innovative materials with high efficiency that positively impact the healing process. Nanoparticles have been extensively used in wound dressings because of their specific properties, such as a high surface area‐to‐volume ratio, increased surface reactivity, and improved biocompatibility, representing a unique tissue repair tool. This review article addresses advances in the use of organic nanoparticles in the field of skin regeneration, considering papers published in the last 5 years, and highlighting the effects of this class of materials on the wound healing process. The analysis of the literature shows that the materials being considered are carbon‐based and organic materials, including polymeric, cellulosic, lipid, and liposome nanoparticles, which are covered in this review (inorganic nanoparticles are not considered). Furthermore, important aspects to prevent the development of chronic wounds are presented, as well as general characteristics of wounds, the healing process, and their particularities.
5 November 2024 in Polymers for Advanced Technologies
Skin injuries occur when cellular integrity is compromised due to mechanical, physical, or metabolic factors. This study reported on a carboxymethylcellulose (CMC)‐based film incorporating TiNT, aiming at its application as a wound dressing. As a minimally invasive approach, titanate nanotubes (TiNT) have been studied due to their photocatalytic properties, biocompatibility, large pore volume, and high surface area. Functionalization with aminosilane groups, using the biological responses of nitrogen, has been explored to enhance cellular interaction. Upon exposure to UV radiation, the dressing releases nanotubes, protecting the lesion from external pathogens and promoting healing. TiNTs were synthesized via a hydrothermal method and 0.2% (v/v) functionalized using 3‐aminopropyltrimethoxysilane (APTMS). The films were prepared with 1 (wt%) TiNT or TiNT_NH2 in a 2 (wt%) CMC solution and dried at 60°C for 24 h. Results showed enhanced thermal stability and the potential for controlled nanoparticle release under UV light, with no cytotoxic effects observed. The films demonstrated excellent biocompatibility, making them promising candidates for medical applications.