Search Results (383)

Background: Maxillomandibular bone defects present a complex challenge in regenerative medicine due to anatomical and functional intricacies. Calcium phosphate (CP)-based biomaterials have emerged as promising bone graft substitutes due to their biocompatibility, osteoconductivity, and bioactivity. Aim: This Review highlights recent clinical and experimental advancements in CP-based biomaterials for maxillomandibular bone regeneration, bridging the gap from bench to bedside. Method: An in vitro, in vivo, and clinical literature review was conducted to evaluate the performance of CP ceramics, including hydroxyapatite (HA), tricalcium phosphate (TCP), biphasic ceramics, and novel composites with polymers, growth factors, and nanoparticles. Results: Calcium phosphate-based biomaterials demonstrate excellent bone regeneration potential, with Beta-tricalcium phosphate (β-TCP) and HA being the most widely utilized. Composite scaffolds and 3-dimensional (3D)-printed constructs show enhanced mechanical properties and biological integration. Clinical trials have confirmed the safety and efficacy of CP-based materials, yielding promising outcomes in osteoconduction and defect healing. However, limitations persist regarding mechanical strength and long-term degradation profiles. Conclusions: CP-based biomaterials offer significant clinical promise for maxillomandibular bone regeneration. Continued advancements in scaffold design and biofunctionalization are crucial for overcoming current limitations and fully realizing their therapeutic potential. Full article

Objective: Yttria-stabilized tetragonal zirconia polycrystal (Y-TZP), a variant of zirconia (ZrO₂), has attracted interest as a substitute for titanium in dental and orthopedic implants, valued for its biocompatibility and aesthetics that resemble natural teeth. However, its bioinert surface limits osseointegration, making surface modifications such as calcium phosphate (CaP) coatings highly relevant. Materials and methods: The review process adhered to the PRISMA guidelines. Electronic searches of PubMed, Scopus, Web of Science, Embase, and Cochrane Library (July 2025) identified studies evaluating CaP-coated zirconia implants. Eligible studies included in vitro, in vivo, and preclinical investigations with a control group. Data on coating type, deposition method, and biological outcomes were extracted and analyzed. Results: A total of 27 studies were analyzed, featuring different calcium phosphate (CaP) coatings including β-tricalcium phosphate (β-TCP), hydroxyapatite (HA), octacalcium phosphate (OCP), and various composites. These coatings were applied using diverse techniques such as RF magnetron sputtering, sol–gel processing, biomimetic methods, and laser-based approaches. In multiple investigations, calcium phosphate coatings enhanced osteoblast attachment, proliferation, alkaline phosphatase (ALP) expression, and bone-to-implant contact (BIC) relative to unmodified zirconia surfaces. Multifunctional coatings incorporating growth factors, antibiotics, or nanoparticles showed additional benefits. Conclusion: CaP coatings enhance the bioactivity of zirconia implants and represent a promising strategy to overcome their inertness. Further standardized approaches and long-term studies are essential to verify their translational relevance. Full article

The ion doping of hydroxyapatite (HA) has gained appeal as a chemical method of improving and adding new characteristics to materials used in biomedical engineering. Dimension, morphology, porosity, surface charge, topology, composition, and other material characteristics make doped HA more suitable for specific biomedical applications. The main aim of this review study was to highlight the role of iHA (iHA) in developing drug delivery systems, tissue engineering, implant coating, wound healing, and multimodal imaging. To the best of our knowledge, depending on the dopant, iHA can have inherent distinct mechanical, physicochemical, and biological properties that make it eligible for biomedical application. More importantly, some ions make iHA a potent antibacterial agent and drug carrier for wound healing (e.g., silver, copper, zinc), have tissue engineering capabilities, improved proangiogenic and osteoconductive properties (e.g., strontium, cobalt, nickel), drug loading capacity (e.g., magnesium, ferric, strontium), metallic implant coating properties (e.g., manganese, silver, copper), and multimodal imaging potential (e.g., terbium, ytterbium, cerium). The concentration of ions and the number of dopants played a vital role in developing new approaches based on iHA. In conclusion, iHA, compared to HA, could show better improvements in biomedical applications. Full article

Efficient use of nitrogen and phosphorus is crucial for achieving sustainable wheat production. Slow-release nano-fertilizers offer a targeted strategy to minimize nutrient losses, reduce excessive fertilizer application, and improve crop yield. This study introduces urea–hydroxyapatite (n-UHA) nanohybrid as a slow-release fertilizer synthesized to enhance nitrogen (N) and phosphorus (P) delivery efficiency in wheat (Triticum aestivum L.). Physical characterization techniques, including Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectroscopy (EDS), Zetasizer, and Fourier Transform Infrared Spectroscopy (FTIR), confirmed the formation of spherical n-UHA with a particle size of 106 nm. FTIR results indicated the formation of physically bound urea as a coating layer on the particle surface. Foliar application of n-UHA at 2500 and 5000 ppm N significantly increased tiller intensity and grain yield compared to conventional urea. The highest biological yield, approximately 16 t ha⁻¹, was achieved with 5000 ppm n-UHA plus supplemental soil phosphorus (P), representing a 4-fold increase over the control. Conventional urea treatments, in comparison, only doubled yield. Notably, increasing conventional urea concentration from 2500 to 5000 ppm N did not significantly increase the yield even with additional P-soil supplement, while applying 5000 ppm N from n-UHA with supplemental P provided an approximate 25% yield increase compared to 2500 ppm n-UHA without P. The n-UHA’s slow-release mechanism supported prolonged tiller intensity, enhanced protein content, and higher biomass yield and chlorophyll content. This study showed that the slow-release mechanism of urea in the monohybrid due to hydrolysis resulted in localized acidity from carbonic acid production on the leaf surface area and contributed to dissociating phosphate ions from hydroxyapatite, making phosphorous more accessible. The enhanced performance of n-UHA is due to its controlled nutrient release, enabled by the physical binding of urea with hydroxyapatite nanoparticles. This binding ensures a synchronized supply of nitrogen and phosphorus aligned with plant demand. The nano-hydroxyapatite composite (N/Ca 6:1) supplies balanced nutrients via efficient stomatal absorption and gradual release. As an eco-friendly alternative to conventional fertilizers, n-UHA improves nitrogen delivery efficiency and reduces N-evaporation, supporting sustainable agriculture. Full article

Periodontal disease in dogs leads to progressive bone loss and adversely impacts overall health. However, cost-effective regenerative strategies are still limited in veterinary practice. This study aimed to develop and evaluate a novel tannic acid (TA)–gelatin-based hydrogel (Gel), incorporating graphene oxide (GO) and hydroxyapatite nanoparticles (HA), as a potential barrier material for guided tissue regeneration (GTR) applications. The hydrogels—Gel, Gel-GO, Gel-HA, and Gel-GO-HA—were characterized for chemical structure, molecular interactions, surface morphology, nanoparticle dispersion, and tensile strength. Cytotoxicity was assessed using L929 fibroblasts (ISO 10993-5), while cell viability/proliferation, morphology, and alkaline phosphatase (ALP) production were evaluated using canine periodontal ligament-derived cells. Results show that crosslinking with tannic acid enhanced the incorporation of graphene oxide and hydroxyapatite nanoparticles via hydrogen bonding into TA–gelatin-based hydrogels. This combination increased surface roughness, reduced degradation rate, and enabled shape memory behavior, critical for guided tissue regeneration (GTR) membranes. The extracts from Gel-HA-GO showed that cytotoxicity was both time- and concentration-dependent in L929 fibroblasts, whereas enhanced cell proliferation and increased ALP production were observed in cultures derived from canine periodontal ligament cells. These findings suggest that TA–gelatin-based hydrogels incorporating GO and HA demonstrated favorable mechanical and physicochemical properties, biocompatibility, and osteogenic potential. These attributes suggest their viability as a promising composite for the development of innovative GTR strategies to address periodontal tissue loss in veterinary medicine. Full article

Small interfering RNAs (siRNAs) are particularly attractive among the frontier drugs due to their high specificity of action, activity on disease-inducing genes, and small molecular weight, thus being one of the most studied agents for gene therapy. However, siRNAs are prone to fast enzymatic degradation in the bloodstream, as well as other limitations that challenge their clinical translation. Nanoparticle (NP) delivery of siRNA has been proposed as a potential solution, overcoming their intrinsic limitations. In this regard, the siRNA delivery by magnetic nanoparticles is of particular interest because, being susceptible to external magnetic fields, it may be guided remotely, maximizing transfection efficiency and minimizing side effects. In addition, magnetic NPs would also allow a theranostic combination of drug delivery, magnetic resonance imaging, and hyperthermia. In this work we have studied the uptake of a model therapeutic siRNA by iron-doped hydroxyapatite nanoparticles (FeHA NPs), which are known to have excellent biocompatibility and magnetic susceptibility. We discovered that FeHA NPs stabilized by citrate (Cit-FeHA NPs) uptake siRNA by adsorption quickly and with high efficiency (ca. 90%) without altering nanoparticles physicochemical properties or colloidal stability. SiRNA-loaded Cit-FeHA NPs are able to slowly release their payload, with a sustained release of 45 days without siRNA degradation. Our work is therefore the preliminary validation of the suitability of FeHA NPs for magnetically guided delivery of therapeutic siRNAs. Full article

Glass ionomer cements (GICs) are bioactive restorative materials valued for their sustained ion release and remineralisation capacity. However, their long-term interactions with sound enamel and dentine remain underexplored. This 12-month in vitro study aimed to evaluate microstructural and compositional changes in sound dental tissues adjacent to four GICs—Ketac Universal, Fuji IX and Equia Forte Fil (conventional GICs) and the advanced Glass Carbomer (incorporating hydroxyapatite nanoparticles)—using field-emission scanning electron microscopy (FE-SEM) and energy-dispersive X-ray spectroscopy (EDS). Glass Carbomer uniquely formed hydroxyapatite nanoparticles and mineralised regions indicative of active biomineralisation—features not observed with conventional GICs. It also demonstrated greater fluoride uptake into dentine and higher silicon incorporation in both enamel and dentine. Conventional GICs exhibited filler particle dissolution and mineral deposition within the matrix over time; among them, Equia Forte released the most fluoride while Fuji IX released the most strontium. Notably, ion uptake was consistently higher in dentine than in enamel for all materials. These findings indicate that Glass Carbomer possesses superior bioactivity and mineralising potential which may contribute to the reinforcement of sound dental tissues and the prevention of demineralisation. However, further in vivo studies are required to confirm these effects under physiological conditions. Full article

This study looks at the effect of surface conditioners hydrofluoric acid (HFA), Ytterbium fibre laser (YFL), and Hydroxyapatite nanoparticles (HANPs) on the surface roughness (Ra) and shear bond strength (SBS) of different viscosity resin cements to lithium disilicate glass ceramic (LDC). A total of 78 IPS Emax discs were prepared and categorized into groups based on conditioning methods. Group 1 HFA–Silane (S), Group 2: YFL-S, and Group 3: HANPs-S. A scanning electron microscope (n = 1) and profilometer (n = 5) were used on each conditioned group for the assessment of surface topography and Ra. A total of 20 LDC discs for each conditioned group were subsequently categorized into two subgroups based on the application of high- and low-viscosity dual-cured resin cement. SBS and failure mode were assessed. ANOVA and post hoc Tukey tests were employed to identify significant differences in Ra and SBS among different groups. LDC conditioned with HFA-S, HANPs-S, and YFL-S demonstrated comparable Ra scores (p > 0.05). Also, irrespective of the type of conditioning regime, the use of low-viscosity cement improves bond values when bonded to the LDC. LDC treated with YFL-S and HANPs-S can serve as an effective substitute for HFA-S in enhancing the Ra and surface characteristics of LDC. The low-viscosity resin cement demonstrated superior performance by achieving greater bond strength. Full article

Tomatoes are a fundamental part of the daily diet, rich in carbohydrates, vitamins, minerals, carotenoids, and polyphenols. Nonetheless, optimal fruit yield and quality typically depend on the application of synthetic agrochemicals. However, the irrational use of these agrochemicals has caused various environmental problems. Therefore, it is necessary to develop alternatives to conventional agrochemical products. Applying nanomaterials as fertilizers in tomato production is emerging as a promising approach, with documented improvements in germination, vegetative development, and fruit yield. Therefore, we present a comprehensive review of recent developments (2015–2024) in the application of nanomaterials in tomato crops, with a particular emphasis on the significance of nanomaterial characteristics in their role as fertilizers. Several types of nanomaterials, such as ZnO, Ag, TiO₂, Si, hydroxyapatite, P, Zn, Se, CuO, Cu, Fe, Fe₂O₃, CaO, CaCO₃, and S, have been evaluated as fertilizers for tomato crops, with ZnO nanoparticles being the most extensively studied. However, it is pertinent to conduct further research on the less-explored nanomaterials to gain a deeper understanding of their effects on seed germination, plant growth, and fruit quality and quantity. Full article

Preparing a bioactive surface with a hierarchical micro/nanostructure can improve the osseointegration of titanium implants. In this study, titanium was sand blasted and etched in H₂SO₄ solution to obtain micro-rough morphology. The samples were then hydrothermally treated in the concentrated CaHPO₄ solution at 120–200 °C for 24 h to grow films consisting of anatase TiO₂ and hydroxyapatite nanoparticles (size 80–240 nm). The hydrothermally calcified (200 °C) sample exhibited much better corrosion resistance in the salt solution, as well as similar cellular viability and a higher alkaline phosphatase level in the cell tests using MC3T3-E1 cells, in comparison with the polished titanium sample. The hybrid treatment is a facile and effective method to a form bioactive surface with a hierarchical micro/nanostructure on titanium. Full article

This study investigates the impact of hydroxyapatite (HA) nanoparticles (NPs) on the cellular responses of poly(L-lactide-co-ε-caprolactone) (PLCL) scaffolds in bone tissue engineering applications. Three types of PLCL scaffolds were fabricated, varying in HANPs content. Saos-2 osteoblast-like cells (OBs) and THP-1-derived osteoclast-like cells (OCs) were co-cultured on the scaffolds, and cell proliferation was assessed using the MTS assay. The amount of double-stranded DNA (dsDNA) was quantified to evaluate cell proliferation. Expression levels of OBs and OCs markers were analyzed via quantitative polymerase chain reaction (qPCR) and the production of Collagen type I was visualized using confocal microscopy. Additionally, enzymatic activity of alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP or ACP5) was measured to assess OB and OC function, respectively. Interestingly, despite the scaffold’s structured character supporting the growth of the Saos-2 OBs and THP-1-derived OCs coculture, the incorporation of HANPs did not significantly enhance cellular responses compared to scaffolds without HANPs, except for collagen type I production. These findings suggest the need for further investigation into the potential benefits of HANPs in bone tissue engineering applications. Nevertheless, our study contributes valuable insights into optimizing biomaterial design for bone tissue regeneration, with implications for drug screening and material testing protocols. Full article

Implant-associated infections, particularly those linked to Staphylococcus aureus (S. aureus), continue to compromise the clinical success of β-tricalcium phosphate (β-TCP) implants despite their excellent biocompatibility and osteoconductivity. This investigation aims to tackle these challenges by integrating femtosecond (fs)-laser surface processing with two complementary strategies: ion doping and functionalization with green-synthesized silver nanoparticles (AgNPs). AgNPs were produced via fs-laser photoreduction using green tea leaf extract (GTLE), noted for its anti-inflammatory and antioxidant properties. Fs-laser processing was applied to modify β-TCP scaffolds by systematically varying scanning velocities, fluences, and patterns. Lower scanning velocities generated organized nanostructures with enhanced roughness and wettability, as confirmed by scanning electron microscopy (SEM), optical profilometry, and contact angle measurements, whereas higher laser energies induced significant phase transitions between hydroxyapatite (HA) and α-tricalcium phosphate (α-TCP), as revealed by X-ray diffraction (XRD). AgNP-functionalized scaffolds demonstrated markedly superior antibacterial activity against S. aureus compared to the ion-doped variants, attributed to the synergistic interplay of nanostructure-mediated surface disruption and AgNP-induced bactericidal mechanisms. Although ion-doped scaffolds exhibited limited direct antibacterial effects, they showed concentration-dependent activity in indirect assays, likely due to controlled ion release. Both strategies promoted osteogenic differentiation of human bone marrow mesenchymal stem cells (hBM-MSCs) under defined conditions, albeit with transient cytotoxicity at higher fluences and excessive ion doping. Overall, this approach holds promise for markedly improving antibacterial efficacy and osteogenic compatibility, potentially transforming bone regeneration therapies. Full article

Radiation transfer in layers of densely packed aggregates of hydroxyapatite nanoparticles was studied for a spectral range from 300 to 1100 nm using diffuse reflectance measurements and the modeling of the light transfer properties of the layers. The studied samples of dispersed biogenic hydroxyapatite were obtained from animal bone material (bovine bones) using fast pyrolysis followed by grinding and pressing into tablets. A distinctive feature is the high reflectivity (high albedo) of the obtained samples, which is practically independent of the wavelength in the studied spectral range and comparable to the reflectivity of the diffuse reflectance standard based on Spectralon. The modeling of the light transfer properties of the studied samples within the framework of the effective medium theory (using coherent potential approximation) made it possible to establish the weak dependence of the mean scattering-free path and the mean transport-free path of light propagation in the medium on the wavelength, which is consistent with the features observed in the experiment. Possible prospects for the use of nanostructured hydroxyapatite as photonic material are discussed. Full article

Selenium (Se) is an essential micronutrient, recognized for its role in cellular redox systems and its therapeutic potential in cancer treatment. Organic selenium compounds, particularly selenocystine (SeCys), have demonstrated anticancer efficacy due to the ability to induce apoptosis and enhance the effects of chemotherapy agents. Recent studies have shown that SeCys exhibits selective toxicity against cancer cells while sparing normal cells. Unfortunately, its clinical application is limited by stability and solubility concerns. A possible solution to overcome these hurdles comes from recent advances in functionalized nanomaterials. In this study, we investigate the possible incorporation of SeCys with hydroxyapatite nanoparticles (HASeCys) via various methods (adsorption, co-precipitation, and co-precipitation through thermal decomplexation), resulting in the formation of nanocomposites with elemental selenium. The highest elemental selenium yield was achieved with a thermal decomplexing co-precipitation, highlighting the influence of synthesis parameters on Se allotrope formation. Finally, as a preliminary investigation, the HASeCys samples were tested on a panel of cancer cell lines, showing an interesting activity when the hydroxyapatite nanocrystals were functionalized with both crystalline gray and amorphous red selenium. Full article

The development and analysis of the properties of a new material based on UV-curable acrylate monomers with silicon-containing hydroxyapatite and zinc oxide nanoparticles as an antibacterial component and gelatin was carried out. Using this material in orthopedics and dentistry is very convenient because it covers any surface geometry of metal implants and hardens under ultraviolet light. In this work, sorption properties, changes in porosity, and mechanical properties of the material were investigated. The conditions for obtaining hydroxyapatite (HA) nanoparticles and the presence of silicon oxide nanoparticles and organic for the shell in an aqueous medium were studied for the pH of the medium, the sequence of administration and concentration of the material components, as well as antibacterial properties. This polymer material is partially resorbable. That supports not only the growth of bone cells but also serves as a protective layer. It reduces friction between organic tissues and a metal implant and can be a solution to the problem of the aseptic instability of metal implants. The material can also be used to repair damaged bones and cartilage tissues, especially in cases where the application and curing procedure is performed using laparoscopic methods. In this work, the authors propose a simple and quite cheap method for obtaining material based on photopolymerizable acrylates and natural gelatin with nanoparticles of HA, zinc oxide, and silicon oxide. The method allows one to obtain a composite material with different nanoparticles in a polymer matrix which retain the requisite properties needed such as active-sized HA, antibacterial ZnO, and structure-forming and stability-improving SiO2 nanoparticles. Full article