Vat photopolymerization (VP), including stereolithography (SLA), digital light processing (DLP), and volumetric printing, employs UV or visible light to solidify cell-laden photoactive bioresin contained within a vat in a point-by-point, layer-by-layer, or volumetric manner. VP-based bioprinting has garnered substantial attention in both academia and industry due to its unprecedented control over printing resolution and accuracy, as well as its rapid printing speed. It holds tremendous potential for the fabrication of tissue- and organ-like structures in the field of regenerative medicine. This review summarizes the recent progress of VP in the fields of tissue engineering and regenerative medicine. First, it introduces the mechanism of photopolymerization, followed by an explanation of the printing technique and commonly used biomaterials. Furthermore, the application of VP-based bioprinting in tissue engineering was discussed. Finally, the challenges facing VP-based bioprinting are discussed, and the future trends in VP-based bioprinting are projected.

The emergence of additive manufacturing, commonly referred to as 3D printing, has led to a revolution in the field of biofabrication. Numerous types of 3D bioprinting, including extrusion bioprinting, inkjet bioprinting, and lithography-based bioprinting, have been developed and have played pivotal roles in driving a multitude of pioneering breakthroughs in the fields of tissue engineering and regenerative medicine. Among all the 3D bioprinting methods, light-based bioprinting utilizes light to crosslink or solidify photoreactive biomaterials, offering unprecedented spatiotemporal control over biomaterials and enabling the creation of 3D structures with extremely high resolution and precision. However, the lack of suitable photoactive biomaterials has hindered the application of light-based bioprinting in tissue engineering. The development of photoactive biomaterials has only recently been expanded. Therefore, this review summarizes the latest advancements in light-based 3D bioprinting technologies, including the development of light-based bioprinting techniques, photo-initiators (PIs), and photoactive biomaterials and their corresponding applications. Moreover, the challenges facing bioprinting are discussed, and future development directions are proposed.

The ability of dental materials to induce the mineralization of enamel like hydroxyapatite (HA) is of great importance. In this article, a novel kind of dental restorative material characterized by a mineralization ability was fabricated by photopolymerization. Calcium methacrylate (CMA) was introduced into the classical bisphenol A-glycidyl methacrylate (Bis-GMA) and triethylene glycol dimethacrylate (TEGDMA) dental resin formulation. This functional dental resin (BTCM) was calcium-rich and can be prepared simply by one-step photopolymerization. The influence of CMA on the photopolymerization kinetics, the dental resin’s mechanical properties, and its capacity to induce dynamic in situ HA mineralization were examined. Real-time FTIR, compression modulus, scanning electron microscopy, X-ray spectroscopy, MTT assay, and cell attachment test were carried out. The obtained data were analyzed for statistical significance using analysis of variance (ANOVA). Double bond conversion could be completed in less than 300 s, while the compression modulus of BTCM decreased with the increase in CMA content (30 wt%, 40 wt%, and 50 wt%). After being soaked in Ca(NO₃)₂ and Na₂HPO₄ solutions alternatively, dense HA crystals were found on the surface of the dental resin which contained CMA. The amount of HA increased with the increase in CMA content. The MTT results indicated that BTCM possesses good biocompatibility, while the cell adhesion and proliferation investigation demonstrated that L929 cells can adhere and proliferate well on the surface of BTM. Thus, our approach provides a straightforward, cost-effective, and environmentally friendly solution that has the potential for immediate clinical use.

Photocrosslinked gelatin methacryloyl/methacrylated chitosan (GelMA/CSMA) hydrogels are attractive for biomedical applications but are limited by insufficient mechanical strength. Here, γ-methacryloxypropyltrimethoxysilane (MPTS) was prehydrolyzed and condensed to generate siloxane species retaining polymerizable methacrylate groups, which were subsequently incorporated into the GelMA/CSMA network as a reinforcing phase. The effects of MPTS precursor concentration (2–5% w/v) and prehydrolysis time (12–48 h) on the morphology, viscoelasticity, compressive behavior, cytocompatibility, and DLP printability of the resulting GCM hydrogels were systematically investigated. FTIR confirmed methoxy-group consumption while retaining C=C functionality. SEM showed that increasing MPTS precursor concentration increased the apparent abundance of granular features, whereas prolonged prehydrolysis produced larger structures. XRD indicated a predominantly amorphous MPTS-derived phase. GCM-48 h-5% achieved a storage modulus of 23.5 kPa, compressive modulus of 0.682 MPa, and maximum compressive stress of 1.081 MPa, corresponding to 7.4-, 16.9-, and 4.0-fold increases over the GelMA/CSMA control, respectively. The hydrogels exhibited favorable L929 cytocompatibility and retained DLP printability under 405 nm irradiation. These findings demonstrate that regulating MPTS precursor concentration and prehydrolysis time provides a simple route to mechanically reinforce DLP-printable GelMA/CSMA hydrogels without directly incorporating preformed silica particles.