Background: Aging is associated with progressive structural and functional changes in dentin, reducing its mechanical integrity and increasing vulnerability to damage. Among the most important regulators of dentin physiology are extracellular matrix proteins from the SIBLING family, including Dentin Matrix Protein 1 (DMP-1), Dentin Sialophosphoprotein (DSPP), and Osteopontin (OPN). These proteins are essential for dentin mineralization, collagen organization, and tissue remodeling. Despite their critical role, knowledge about their age-related distribution and correlation with dentin structure and morphology remains limited. Aim: To examine age-dependent changes in the expression of SIBLING proteins (DMP-1, DSPP, OPN) in human dentin and to evaluate their relationship with collagen structure and ultramorphology using polarized light microscopy (PLM), immunohistochemistry (IHC), and scanning electron microscopy (SEM). Materials and Methods: Ninety extracted human teeth were categorized into young (≤17 years), mature (18–50 years), and old (>51 years) groups. IHC was applied to detect protein distribution, PLM to assess collagen organization, and SEM to evaluate dentinal morphology. Results and Conclusions: Aging was associated with increased expression of DMP-1 and OPN and a reduction in DSPP, which is particularly evident in peritubular dentin. Older samples showed collagen disorganization, reduced birefringence, and extensive intratubular mineralization. These findings suggest that age-related alterations in SIBLING proteins contribute to structural changes in dentin, providing new insights relevant to dental care in elderly patients.

Background: Coronavirus disease 2019 (COVID-19) is associated with a wide variety of clinical manifestations. Aim: This study aims to evaluate the levels of angiotensin-converting enzyme 2 (ACE2), metalloprotease 17 (ADAM17), Interleukin-17A (IL-17A), transmembrane serine protease 2 (TMPRSS2), apelin (AP), and vitamin D (VD) biomarkers in nasopharyngeal swab (NPS), serum, and saliva, as well as the change in their values depending on the health status of individuals. Material and methods: The analysis was performed by using enzyme-linked immunosorbent assay (ELISA) methods. Results: Comparing the levels of the investigated markers in saliva, we found significantly elevated ACE2 values in vaccinated patients, followed by those with severe COVID-19, compared to healthy, previously infected, and mild COVID-19 groups. For TMPRSS2, IL-17A, ADAM-17, and AP, values were significantly higher in all non-healthy groups (previously infected, mild, and severe COVID-19) compared to healthy individuals. Serum levels of VD were consistently low across all five studied groups, suggesting values below normal ranges. Analysis of marker data in saliva, NPS, and serum revealed a positive correlation between NPS and serum and saliva and serum, as well as between saliva and NPS for all studied markers. Conclusions: In summary, monitoring changes in biomarkers present in Saliva holds promise as a predictive tool for various diseases. This approach enables the early implementation of preventive measures and protective strategies, potentially improving overall health outcomes.

Background: Calcium silicate-based materials are widely used in retrograde endodontic treatment due to their bioactivity and favorable biological properties. The environmental conditions during setting and the time-dependent release of soluble components may influence cellular responses; however, these factors remain insufficiently investigated. Aim: This in vitro study evaluated the cellular response to three calcium silicate-based materials—MTA+, Biodentine, and NeoPUTTY—after setting under different environmental conditions. Materials and Methods: Cylindrical specimens were allowed to set under three conditions: dry environment, phosphate-buffered saline (PBS), and human blood. Eluates obtained after 1, 3, and 5 days were applied to human BJ fibroblasts. Cell viability, based on metabolic activity measured using the AlamarBlue assay, was evaluated at 48 and 96 h. Biocompatibility was inferred from cell viability, reflecting eluate-mediated effects rather than direct material–cell contact. Results: Cell viability was influenced by both the setting environment and eluate maturation time. PBS-set materials showed variable cellular responses, with high viability at early time points but marked decreases at 96 h for some MTA+ and NeoPUTTY groups. Biodentine demonstrated the most stable cellular response across all conditions. Materials set in blood produced cellular responses comparable to those observed for PBS and dry conditions, with no statistically significant overall reduction in cell viability. Conclusions: Within the limitations of this in vitro eluate-based model, blood exposure during setting had a minimal influence on the cell viability to the tested materials. Among the evaluated materials, Biodentine exhibited the most stable biological profile. These findings reflect time-dependent, eluate-mediated cellular effects and should be interpreted with caution when extrapolating to clinical conditions.

Aim : The study of the tribological properties of dental materials is a growing and rapidly expanding field. The aim of our research is to investigate the micro-scratch and wear resistance of different restorative dental materials. Materials and methods : Three restorative materials indicated for the treatment of dental caries in the distal area of the dentition were used: dental amalgam without γ ₂ phase, with high Ag content (Cavex Non Gamma-2); a microhybrid resin-based composite material (Gradia Direct posterior); a metal alloy (Duceralloy C) was used as a positive control. All specimens were subjected to micro-scratch resistance test in 1 N, 5 N, 9 N mode, a ball-on-flat wear resistance test at 120,000/240,000 cycles loaded at 50 N. The examined surfaces of the specimens were visualized by optical microscopy and by 3D profilometry of all the specimens tested after 240,000 wear cycles. Results : The results are presented in the form of graphs - for each specimen, for each individual test, and for each individual cycle. The wear resistance of Duceralloy C increases after 240,000 cycles. The wear resistance of Cavex Non Gamma-2 and Gradia Direct posterior decreases with increasing time and friction cycles. Conclusion : The results of this study may help to elucidate the wear mechanisms and provide additional information on the expected changes in the materials tested in clinical practice.

Background : During root canal therapy, one of the most often overlooked anatomical structures in maxillary first molars is the second mesiobuccal canal. Even with the use of ultrasonic devices and magnification, its detection remains difficult. Aim : To evaluate whether cone beam computed tomography provides additional clinical benefit for identifying and negotiating the second mesiobuccal canal after exploration under a dental operating microscope combined with ultrasonic troughing. Methods : A total of 129 maxillary first molars undergoing primary endodontic treatment were examined using a two-stage clinical protocol. In the first stage, canal identification was performed under a dental operating microscope and ultrasonic endodontic tips. Teeth in which the second mesiobuccal canal could not be located or fully negotiated proceeded to the second stage, which included a cone beam computed tomography scan. When an additional canal was visualized, a second clinical attempt at detection and negotiation of the MB2 canal was performed. Detection rates, canal morphology, and negotiation outcomes were recorded and analyzed statistically. Results : The second mesiobuccal canal was detected in 79.1% of teeth during microscopic exploration, with full negotiation achieved in most cases. Cone beam computed tomography identified an additional canal in 40.7% of teeth that remained undetected after the first stage. The combined approach resulted in an overall detection rate of 87.6%. Canal morphology, particularly patency and canal confluence, strongly influenced detectability. Conclusion : Cone beam computed tomography provides added value for identifying the second mesiobuccal canal only when microscopic and ultrasonic methods fail. Its benefit depends on anatomical conditions, while favorable morphology remains the key determinant of successful canal detection and negotiation.

The dental pulp–dentin complex is a dynamic tissue system whose structure and biological functions evolve over time under physiological, molecular, and environmental influences. This study aimed to characterize age-related alterations in apoptotic, inflammatory, and autophagy-associated signaling pathways, alongside nanoscale mechanical changes, and to evaluate their potential impact on pulp tissue homeostasis and cellular adaptive capacity. Materials and Methods: Human teeth (n = 90) were divided into three age groups: young (≤17 years), mature (18–50 years), and old (>51 years). Immunohistochemistry was performed to assess the expression of CD34, BID, Caspase-8, NFκB, STAT3, JAK1, COX-2, LAMP2, and MAP LC3II. Nanoindentation and atomic force microscopy (AFM) were used to measure dentin hardness and modulus of elasticity. Results: BID expression increased with age, whereas Caspase-8 showed a relative decrease (p < 0.05). Anterior teeth exhibited higher marker positivity than molars for BID (p = 0.029), Caspase-8 (p = 0.004), STAT3 (p = 0.001), and JAK1 (p = 0.026). Mechanical analysis revealed the lowest modulus of elasticity in young root dentin and the highest in old coronal dentin, reflecting progressive age-dependent structural changes. Conclusions: Aging of the dentin–pulp complex involves coordinated modulation of apoptotic, autophagic, and inflammatory pathways, closely linked to altered mechanical properties. This interplay likely influences pulp vitality and adaptive cellular responses, highlighting potential targets for age-adapted dental therapeutic strategies.