Preparation of a novel regenerated silk fibroin-based hydrogel for extrusion bioprinting

Applications and interventions of polymers and nanomaterials in alveolar bone regeneration and tooth dentistry

Inflammatory diseases exert a significant influence on the periodontium, serving as a primary contributor to the development of periodontitis. The advancement of periodontitis, characterized by manifestations, such as gingival recession, increased periodontal pocket depth and resorption across the alveolar bone, cementum and periodontal ligaments, poses a significant risk of dental detachment. Untreated or delayed treatment further worsens these deleterious outcomes. This emphasizes the critical importance of timely and effective interventions in reducing the consequences associated with periodontitis. Addressing these challenges requires to focus on the fabrication of bioactive materials, particularly scaffolds, as pivotal elements in tissue engineering processes aimed at alveolar bone regeneration. The incorporation of natural polymers, particularly their amalgamation with clays and clay minerals, such as montmorillonite and LAPONITE®, has been identified as a prospective pathway for advancing biomaterials in the realm of dentistry. This amalgamation holds significant potential for the production of biomaterials with enhanced properties, underscoring its relevance and applicability in dental research. This review paper explores the current advancements in natural polymer-based biomaterials employed in various dental applications, including oral caries, regenerative medicine and alveolar bone regeneration. The principal aim of this investigation is to briefly compile and present the existing knowledge while updating information on the utilization of natural polymers in the formulation of biomaterials. Additionally, the paper aims to elucidate their applications within contemporary research trends and developments in the field of odontology. This article extensively delves into pertinent research to assess the progress of nanotechnology in the context of tissue regeneration and the treatment of oral diseases.

Time-programmed release of curcumin and Zn2+ from multi-layered RSF coating modified PET graft for improvement of graft-host integration

Artificial graft serves as the primary grafts used in the clinical management of sports-related injuries. Until now, optimizing its graft-host integration remains a great challenge due to the excessive inflammatory response during the inflammatory phase, coupled with an absence of tissue-inductive capacity during the regeneration phase. Here, a multi-layered regenerated silk fibroin (RSF) coating loaded with curcumin (Cur) and Zn2+ on the surface of the PET grafts (Cur@Zn2+@PET) was designed and fabricated for providing time-matched regulation specifically tailored to address issues arising at both inflammatory and regeneration phases, respectively. The release of Cur and Zn2+ from the Cur@Zn2+@PET followed a time-programmed pattern in vitro. Specifically, cellular assays revealed that Cur@Zn2+@PET initially released Cur during the inflammatory phase, thereby markedly inhibit the expression of inflammatory cytokines TNF-a and IL-1β. Meanwhile, a significant release of Zn2+ was major part during the regeneration phase, serving to induce the osteogenic differentiation of rBMSC. Furthermore, rat model of anterior cruciate ligament reconstruction (ACLR) showed that through time-programmed drug release, Cur@Zn2+@PET could suppress the formation of fibrous interface (FI) caused by inflammatory response, combined with significant new bone (NB) formation during regeneration phase. Consequently, the implementation of the Cur@Zn2+@PET characterized by its time-programmed release patterns hold considerable promise for improving graft-host integration for sports-related injuries.

Effect of Sericin Content on the Structural Characteristics and Properties of New Silk Nonwoven Fabrics

Recently, natural silk nonwoven fabrics have attracted attention in biomedical and cosmetic applications because of their excellent biocompatibility, mechanical properties, and easy preparation. Herein, silk nonwoven fabrics were prepared by carding silk filaments to improve their productivity, and the effect of sericin content on the structure and properties of silk nonwoven fabrics was investigated. Owing to the binding effect of sericin in silk, a natural silk nonwoven fabric was successfully prepared through carding, wetting, and hot press treatments. Sericin content affected the structural characteristics and properties of the silk nonwoven fabrics. As the sericin content increased, the silk nonwoven fabrics became more compact with reduced porosity and thickness. Further, with increasing sericin content, the crystallinity and elongation of the silk nonwoven fabrics decreased while the moisture regain and the maximum stress increased. The thermal stability of most silk nonwoven fabrics was not affected by the sericin content. However, silk nonwoven fabrics without sericin had a lower thermal decomposition temperature than other nonwoven fabrics. Regardless of the sericin content, all silk nonwoven fabrics exhibited optimal cell viability and are promising candidates for cosmetic and biomedical applications.

Application of Silk-Fibroin-Based Hydrogels in Tissue Engineering

Silk fibroin (SF) is an excellent protein-based biomaterial produced by the degumming and purification of silk from cocoons of the Bombyx mori through alkali or enzymatic treatments. SF exhibits excellent biological properties, such as mechanical properties, biocompatibility, biodegradability, bioabsorbability, low immunogenicity, and tunability, making it a versatile material widely applied in biological fields, particularly in tissue engineering. In tissue engineering, SF is often fabricated into hydrogel form, with the advantages of added materials. SF hydrogels have mostly been studied for their use in tissue regeneration by enhancing cell activity at the tissue defect site or counteracting tissue-damage-related factors. This review focuses on SF hydrogels, firstly summarizing the fabrication and properties of SF and SF hydrogels and then detailing the regenerative effects of SF hydrogels as scaffolds in cartilage, bone, skin, cornea, teeth, and eardrum in recent years.