Two-dimensional culture systems have been used for a long time in the research field but their disadvantages make it difficult to reproduce the in vivo environment. Three-dimensional culture systems overcome these limitations, simulating the physiological context of an organism, from the molecular level to the cellular, tissue, and organ complexity levels. This review focuses on 3D cellular models, such as spheroids and tumoroids, which reproduce tumor heterogeneity and microenvironments. It also includes 3D cultures of mesenchymal stem cells (MSCs), particularly those derived from teeth. In conclusion, 3D models are profoundly impacting the biomedical field by offering more accurate in vitro platforms for drug development and disease modeling, thereby significantly reducing the reliance on animal testing and leading to the advancement of personalized and regenerative medicine.

Regenerative medicine is the branch of medicine that aims to repair and regenerate damaged tissues and presents promising avenues for addressing a wide range of currently incurable diseases. Regenerative medicine is based on the use of cell therapy with stem cells that can differentiate into differentiated cells of specific tissues. There are various types of stem cells, which are different in potential and derivation. The aim of this review is to summarize the types of stem cells most studied and recently discovered, from adult stem cells to innovative induced pluripotent stem cells (iPSCs), for regenerative medicine purposes. The stem cells involved in the identification of new regenerative therapeutic approaches are analyzed here through a classification based on the tissues’ embryonic derivation: stem cells from ectodermal derivation tissues, stem cells from mesodermal derivation tissues, stem cells from endodermal derivation tissues, and iPSCs.

The use of temporary resin for provisional restorations is a fundamental step to maintain the position of prepared teeth, to protect the pulpal vitality and the periodontal health as well as the occlusion. The present study aimed at evaluating the biological effects of two resins used in dentistry for temporary restorations, Coldpac (Yates Motloid) and ProTemp 4™ (3M ESPE ™), and their eluates, in an in vitro model of human gingival fibroblasts (hGFs). The activation of the inflammatory pathway NFκB p65/NLRP3/IL-1β induced by the self-curing resin disks was evaluated by real-time PCR, Western blotting and immunofluorescence analysis. The hGFs adhesion on resin disks was investigated by means of inverted light microscopy and scanning electron microscopy (SEM). Our results suggest that hGF cells cultured in adhesion and with eluate derived from ProTemp 4™ (3M ESPE ™) resin evidenced a downregulation in the expression of the inflammatory mediators such as NFκB p65, NLRP3 and IL-1β compared to the cells cultured with Coldpac (Yates Motloid) after 24 h and 1 week of culture. Furthermore, the cells cultured with ProTemp 4™ (3M ESPE ™) after 24 h and 1 week of culture reported a higher cell viability compared to the cells cultured with Coldpac (Yates Motloid), established by MTS cell analysis. Similar results were obtained when hGFs were placed in culture with the eluate derived from ProTemp 4™ (3M ESPE ™) resin which showed a higher cell viability compared to the cells cultured with eluate derived from Coldpac (Yates Motloid). These results highlighted the lower pro-inflammatory action and improved cell biocompatibility of ProTemp 4™ (3M ESPE ™), suggesting a better performance in terms of cells–material interaction.

The use of dental composite resins has significantly increased over recent years, thanks to their esthetics and mechanical features, despite some doubts being raised about their biocompatibility. Residual methacrylate can be eluted from bulk composites, and its amount may significantly increase over time, leading to cytotoxic effects that can involve several inflammatory patterns. The aim of this in vitro study was to evaluate the activation of the inflammatory pathway NFκB p65/MyD88/NALP3 and the apoptosis pathway of BCL-2/BAX/Caspase-3 (CASP-3) expression on human gingival fibroblasts (hGFs) after 24 h and 1-week exposure to the eluates of three heat-cured dental composite resins: GrandioSO, VOCO (GR); Enamel Plus HRi Biofunction, Micerium (BF); and Filtek universal restorative, 3M (FU). The results highlighted that NFκB p65/MyD88/NALP3 was activated after resin exposure in a time-dependent manner. Moreover, immunofluorescence and gene expression analyses showed that pro-apoptotic markers CASP-3 and BAX were elevated, while anti-apoptotic protein BCL-2 was suppressed in hGFs after dental resin exposure. The present in vitro study analyzed mechanisms related to cytotoxicity and apoptosis, suggesting ways to limit composite cytotoxicity through advancements in material technology. The activation of inflammation and apoptotic pathways appeared to be material-dependent, and was less pronounced with BF and FU, which could hypothetically indicate them being a safer clinical choice to preserve periodontal health in daily dental practice.

Barrier function regulation, angiogenic potential, and immune response modulation are only a few of the many roles of the vascular system that nowadays represent one of the main targets for environmental pollutants, in particular, pesticides. We have used human umbilical vein endothelial cells (HUVECs) as an in vitro model to investigate the effects of pesticides on the activation of the NALP3-CASP1-IL-1β inflammatory pathway using real time PCR (RT-PCR) and immunofluorescence investigations, reactive oxygen species (ROS) generation, and morphological alterations with scanning electron microscopy (SEM) analysis. Our findings offer a comprehensive evaluation of the cellular and molecular damage induced by pesticide exposure and show strong inflammasome activation. They indicate that these chemicals may initiate necroptosis and drive prolonged inflammation in endothelial cells. This study provides crucial insights into how pesticides contribute to endothelial dysfunction, highlighting the need for further investigation into their inflammatory and immune-modulatory effects on vascular health.

This in vitro study aimed to analyze the activation of the NFκB p65/MyD88/NALP3 inflammatory pathway and the expression of the BCL-2/BAX/Caspase-3 apoptosis pathway on human gingival fibroblasts (hGFs) after 24 h and 1-week exposure to the eluates of three light-cured commercial composites (GR: GrandioSO, VOCO; BF: Enamel Plus HRi Biofunction, Micerium; FU: Filtek universal restorative, 3M) and the production of pro-inflammatory cytokines (TNF-α, IL-6, IL-1β). A total of 50 light-cured disk-shaped specimens for each composite group (GR, BF and FU) were produced. The tested materials differed in resin matrix composition; notably, GR contained Bis-GMA, whereas BF and FU contained urethane-based dimethacrylates. The hGFs were exposed for 24 h and 1 week to eluates of each group. Pathway activation was evaluated by cell metabolic activity, immunofluorescence analysis and real-time PCR. Inflammatory effects were assessed in hGF culture by measuring proinflammatory cytokine production (ELISA). GR, BF and FU showed a reduction in metabolic activity in a time-dependent manner. GR showed a significant decrease in terms of cell viability after 1 week of exposure and a greater expression of proapoptotic markers than BF and FU. High levels of proinflammatory cytokines were measured after 1 week of culture for GR. The inflammatory pathway was activated in a time-dependent manner. Pathway activation was material-dependent; among the tested composites, GR was found to be more cytotoxic than BF and FU. Despite the limitations of an in vitro study, these findings suggest that dental composite eluates cause time- and material-dependent cytotoxicity, inflammation, and apoptosis in hGFs. Exposure significantly impairs cellular metabolic activity from 24 h up to 1 week. Among the evaluated materials, the GR composite triggered a markedly severe inflammatory and apoptotic effect compared to BF or FU. Ultimately, these findings underscore the potential clinical importance of selecting materials with optimal biocompatibility to minimize adverse tissue reactions, although their direct translation into clinical practice would require further research.