Research progress on injectable hydrogel scaffolds in dental pulp regeneration / 口腔疾病防治

@#Tissue engineering provides a new possibility for pulp regeneration. As one of the three elements of tissue engineering, scaffolds have attracted increasing attention. Because the root canal system is limited by the unique anatomical structure of the long and narrow lumen, the preformed scaffold cannot be completely covered with the whole root canal space, although it is convenient to apply, so the injectable scaffold may be an ideal choice for pulp tissue engineering. Hydrogels are hydrophilic polymer networks with physical properties similar to soft tissues. They can provide a porous hydrophilic microenvironment, which facilitates the diffusion of oxygen and nutrients. In recent years, researchers have used injectable hydrogels with different mechanical properties and/or loaded biologically active ingredients as scaffolds to promote revascularization and the regeneration of pulp. The results show that natural polymer hydrogels, synthetic polymer hydrogels, and composite hydrogels combining natural and synthetic polymers all have excellent biocompatibility. The types and mechanical properties of hydrogels and the addition of bioactive ingredients can influence the behavior of stem cells, and gelatin-based hydrogels and fibrin-based hydrogels can also achieve rapid vascularization, which creates the conditions for the formation of pulp-like tissues. Among them, photocrosslinked methacrylated gelatin/hyaluronic acid hydrogels, two/multicomponent hydrogels combined with chitosan with antibacterial and temperature-sensitive properties and new self-assembled peptides have become major research topics in recent years due to their excellent properties. To develop suitable hydrogel scaffolds and promote their application in pulp regeneration, this article reviews the research progress in the types, preparation, and application of injectable hydrogels used for dental pulp regeneration.

Research progress of scaffolds for promoting the vascularization of regenerated dental pulp / 口腔疾病防治

@#Endothelial regeneration is a research hotspot in the field of dental pulp. The regeneration of endodontic blood flow is the bottleneck of dental pulp regeneration, and the applied scaffold material is the key to revascularization. Stent materials were reviewed. The literature review Results show that, depending on the source of the stent material used for endodontic revascularization, there are mainly natural, synthetic and composite materials. The natural scaffold materials used for vascular regeneration include chitosan, hyaluronic acid, bacterial cellulose, and proanthocyanidin; artificial scaffold materials include hydrogel, cryogel, and electrospinning. The bionic composite scaffold system with a double-layer tubular structure is low immunogenicity and good biocompatibility. Studies on the scaffold materials of bionic extracellular matrix, such as injectable hydrogels/microspheres, have promoted the development of dental pulp regeneration, that is, uniformly distributed scaffold materials in the root canal promote the generation of pulp-like tissue; Whether dental pulp tissue can establish effective blood circulation through the apical foramen remains a great challenge.

Research progress of pulpotomy and crown pulp regeneration / 口腔疾病防治

@#Crown pulp regeneration is a method to replace the pulp-capping agent with stem cells and scaffold structures, which are placed on the section of healthy root pulp tissue after pulpotomy to regenerate the pulp-dentin complex in the crown. This paper reviews the significance, physiological basis, application and challenges of crown pulp regeneration to provide new ideas for the study of pulp regeneration. The results of a literature review show that the combination of traditional pulpotomy, stem cell biology and tissue engineering, as well as the regeneration of crowns and pulp by using the tissue repair potential of healthy root pulp can effectively promote the regeneration of dentin and parts of pulp. In recent years, with the development of research on pulp regeneration, many challenges have been gradually revealed. It is necessary not only to select the treatment methods that can promote the proliferation and differentiation of dental pulp stem cells safely and effectively but also to continue to explore the scaffold materials suitable for the structural and functional diversity of the pulp chamber.