Journal of Functional Biomaterials最新文献

Titanium-based alloys are widely used in dental implantology; however, the mechanical limitations of commercially pure titanium (cpTi) and unresolved concerns regarding stress shielding remain. This study evaluated the structure-property-function relationship of a novel β-type titanium-niobium-zirconium (Ti-Nb-Zr; TNZ) alloy for dental implant applications. Laboratory testing assessed the elemental composition, tensile properties, and fatigue resistance of the cpTi, compared with modified Grade 4 cpTi (MG4T). In parallel, a randomized, single-blind, controlled clinical trial was conducted over 12 months to compare the clinical performance of TNZ and MG4T implants under functional loading. A total of 80 participants (mean age: 54.2 years; 43 females, 37 males) were enrolled, with 77 completing the 12-month follow-up (TNZ: n = 38; MG4T: n = 39). Clinical outcomes included implant success and survival, peri-implant soft tissue parameters, marginal bone levels, fractal dimension (FD) analysis of trabecular bone, and adverse events. TNZ implants demonstrated superior fatigue resistance without an increase in the elastic modulus relative to MG4T. Clinically, both groups achieved 100% implant success and survival, with no implant-related adverse events. FD analysis revealed time-dependent bone remodeling without evidence of pathological adaptation. These findings support the functional viability of TNZ as a mechanically robust, biocompatible implant material. Further long-term, multicenter trials are warranted to confirm sustained clinical benefits and broader applicability.

Large bone defects remain a major clinical challenge, as current treatments primarily provide mechanical stability while often insufficiently addressing the biological microenvironment. The cell-deposited extracellular matrix (CD-ECM) represents a promising strategy to improve implant bioactivity by mimicking key features of the native tissue. In this study, we compared CD-ECMs from adipose tissue-derived mesenchymal stromal cells (ASCs), ASC-derived osteoprogenitor cells, and dermal fibroblasts. ECM composition was analyzed, and its ability to support the osteogenesis of reseeded skeletal stem cells (SSCs) was assessed. Subsequently, the best performing cells were used to produce CD-ECM on a 3D scaffold. Furthermore, we improved the ECM by treating the ECM-producing cells with dextran sulfate (Dx-S). Fibroblast-derived ECM showed higher collagen and glycosaminoglycan contents compared to ASC-ECM or osteoprogenitor-ECM. Furthermore, only the fibroblast-derived ECM (Fibro-ECM) exerted a supportive effect on the osteogenesis of SSCs. SSCs seeded on ECM showed a higher proliferation rate and enhanced osteogenesis. Supplementation with dextran sulfate further increased ECM deposition and osteogenic potential. We showed that fibroblasts produced substantially more ECM with a stronger pro-osteogenic effect than ASCs or osteoprogenitor cells. The ECM and its pro-osteogenic effect could further be increased when fibroblasts were treated with Dx-S. Together, these results highlight Fibro-ECM as a promising and easily accessible cell-derived ECM deposition strategy to improve the biological performance of implants in bone regeneration.

Background/objectives: Aberrant metabolism in tumors exacerbates the immunosuppressive tumor microenvironment. The immunosuppressive metabolite kynurenine inhibits the activation of effector T cells. Current antitumor drugs targeting kynurenine focus on small molecule inhibitors, which exhibit suboptimal efficacy in suppressing kynurenine generation owing to the diversity of kynurenine synthesis pathways. In contrast, kynureninase (KYNase) can directly metabolize kynurenine regardless of the production source. However, its delivery is hindered by short blood-circulation half-life and poor tumor accumulation. Additionally, photodynamic therapy (PDT) has been reported to synergize with immunotherapy, suggesting a potential combinatorial photodynamic immunometabolic cancer therapy with KYNase.

Methods: A KYNase-Fc fusion protein was prepared to prolong blood circulation and enhance tumor accumulation of KYNase. Meanwhile, KYNase-Fc served as a nanocarrier for photosensitizer pheophorbide A (PhA) due to the high binding affinity between KYNase-Fc and PhA. Through self-assembly, KYNase-Fc/PhA nanoparticles (KYNase-Fc/PhA NPs) were prepared without extra carrier materials.

Results: Compared with the PEGylated KYNase, KYNase-Fc exhibited significantly prolonged blood circulation, enhanced tumor accumulation and effective tumor suppression. Moreover, the prepared KYNase-Fc/PhA NPs facilitated rapid PhA tumor accumulation. The combined photodynamic immunometabolic therapy alleviated the immunosuppressive microenvironment and significantly inhibited the growth of subcutaneous 4T1 tumors in mice.

Conclusions: KYNase-Fc offered a carrier-free nanomedicine for co-delivery of PhA for photodynamic immunometabolic antitumor therapy with enhanced efficacy, providing a promising platform for clinical translation.

Alveolitis remains a common postoperative complication following tooth extraction, characterized by inflammation and delayed socket healing. Collagen-based materials have shown promise in promoting tissue regeneration and reducing inflammation. This review evaluates the efficacy of collagen in the prevention of alveolitis, with a focus on the development and application of topical delivery systems such as gels and collagen sponges. Special attention is given to the local application of these systems within the extraction socket and their performance under oral conditions. The study analyzes current evidence on the pathogenesis of alveolitis, the biological properties of collagen relevant to wound healing, and pharmaceutical strategies for enhancing its clinical effectiveness. The findings support the feasibility of using biodegradable, site-specific collagen-based formulations for alveolitis prevention. Such systems may provide a prolonged therapeutic effect, stabilize blood clots, reduce microbial contamination, and support angiogenesis and osteogenesis throughout the healing process. This approach offers a promising direction for improving post-extraction management protocols in dental surgery.

Ion-releasing restorative biomaterials have gained increasing attention in minimally invasive dentistry due to their potential to combine mechanical reliability with therapeutic functionality. Cention^® N is an alkasite-based restorative material designed to release fluoride, calcium, and hydroxyl ions while exhibiting mechanical properties comparable to resin-based composites. The present study aimed to systematically evaluate the clinical performance of this ion-releasing restorative material in comparison with conventional resin composites and glass ionomer cements. A comprehensive systematic search was conducted in PubMed (MEDLINE), Cochrane Library, Web of Science, Scopus, EMBASE, and SciELO databases up to 31 October 2024, following the PRISMA guidelines. Clinical studies assessing restorative performance outcomes were included. Meta-analyses were performed using Review Manager software (version 5.1). Fourteen studies met the inclusion criteria for qualitative synthesis, of which ten were eligible for quantitative analysis. The pooled results demonstrated comparable clinical performance between alkasite restoratives and resin-based composites regarding retention and secondary caries incidence, while superior outcomes were observed when compared with glass ionomer cements. Within the limitations of the available evidence, ion-releasing alkasite restorative materials represent a clinically acceptable alternative to conventional restorative options, combining functional biomaterial properties with reliable clinical performance. The conclusions should be interpreted within the context of the included studies, which exhibited clinical heterogeneity and, in several cases, a moderate risk of bias.

Biomaterial processing is a crucial operation that involves mechanical and chemical treatments to transform a source material into a biocompatible and bioactive product tailored to a specific medical application [...].

This study systematically optimised extrusion-printing parameters for polyhydroxybutyrate (PHB) using a Design of Experiment (DoE) approach to improve printability and construct fidelity. A five-factor DoE was conducted to evaluate the individual and interactive effects of printhead temperature, printing pressure, printing speed, bed temperature, and cartridge heating time on the dimensional accuracy of printed constructs. The resulting regression model enabled the identification of statistically significant main and interaction effects among processing variables. An optimised parameter set (printhead temperature 145 °C, pressure 150 kPa, speed 15 mm s^-1, bed temperature 25 °C, and cartridge heating time 120 s) enabled the fabrication of PHB scaffolds with substantially improved shape fidelity, which was experimentally validated using verification prints. These results demonstrate that a DoE-based optimisation strategy provides a robust and efficient route for rationally tuning PHB extrusion-printing conditions, thereby enhancing process reliability for scaffold fabrication in regenerative medicine applications.

This in vitro study evaluated the shear bond strength (SBS) and adhesive remnant index (ARI) of orthodontic molar tubes bonded using conventional, hydrophilic, and self-etch adhesives under dry and saliva-contaminated conditions, while also assessing the impact of shear force direction. Extracted molars were bonded with Transbond XT™ (T), Transbond MIP™ (M), or Scotchbond Universal™ (S) under dry or saliva-contaminated conditions. Debonding was performed at 90° or 45°, introducing a clinically relevant but underexplored variable in orthodontic bond-strength testing. ARI scores were assessed via stereomicroscopy and visual inspection. Statistical tests (Kruskal-Wallis and Mann-Whitney) showed no significant SBS differences among adhesives under identical conditions (p > 0.05). However, all adhesives exhibited significantly reduced SBS under saliva contamination (p < 0.001; T: 5.4 vs. 4.1 MPa; M: 5.7 vs. 3.6 MPa; S: 5.5 vs. 4.5 MPa). In dry conditions, SBS was significantly higher with 45° debonding (p < 0.05). Under contamination, SBS varied by ARI score (p = 0.05), with ARI 0 specimens showing higher SBS than ARI 3. These findings confirm that moisture reduces bond strength across adhesive types, while 45° force application enhances SBS under dry conditions. ARI score variability under contamination may reflect complex failure modes.

Titanium dioxide nanotubes (TNTs) have favorable biocompatibility and nanoscale morphologies, and they have been extensively explored for titanium implant surface modifications. However, they are limited by their mechanical strength and weak interfacial adhesion between the nanotube layer and the titanium substrate. This restricts their clinical applications. In this study, a two-step electrochemical anodization method is developed to achieve in situ tantalum (Ta) doping into TNT arrays to enhance their mechanical performance without altering their nanotubular structure. The surface morphology, element and crystal phase composition, surface roughness, wettability, and mechanical properties of the Ta-doped TNTs were then thoroughly characterized. Scanning electron microscopy revealed that the Ta doping did not change the nanotube architecture. In addition, X-ray diffraction confirmed anatase TiO₂ formation in all the samples. X-ray photoelectron spectroscopy demonstrated that Ta⁵⁺ doping significantly reduced oxygen vacancies, and this was a concentration-dependent effect. Nanoindentation and scratch tests showed that the hardness, the Young's modulus of the nanotube layer, and the adhesion strength between the nanotubes and the titanium substrate were markedly improved compared to those of the undoped TNTs. These mechanical enhancements may be attributed to lattice densification due to Ta doping. In vitro cell assays further demonstrated that the Ta-TNTs promoted rat bone marrow mesenchymal stem cell adhesion, proliferation, and osteogenic differentiation. This was evidenced by increased alkaline phosphatase activity, enhanced mineralization, and upregulated gene expression levels. The results suggest that the Ta-doped TNTs offer a pathway for the development of mechanically robust and bioactive implant surfaces for dental and orthopedic applications.

Context: The increasing incidence of secondary caries and the failure of restorations have intensified research into dental restorative materials capable of actively interacting with the oral environment. In this context, antibacterial and bioregenerative nanomaterials have attracted growing scientific interest due to their potential to inhibit biofilm formation while simultaneously supporting mineral repair processes.

Objective: This narrative review analyzes recent developments in nanostructured materials for restorative dentistry and oral health applications, with particular emphasis on antibacterial agents, bioactive systems, and emerging dual-function approaches that integrate multiple biological functions into restorative materials.

Scope of the review: The analyzed literature indicates that metallic nanoparticles, cationic monomers, and natural nanopolymers can reduce bacterial adhesion and metabolic activity under experimental conditions. In parallel, bioactive nanomaterials such as nanohydroxyapatite, bioactive glass, and calcium phosphate-based systems have demonstrated the ability to release remineralizing ions and to promote mineral deposition at the tooth-material interface. Dual-function hybrid materials aim to combine these antibacterial and bioregenerative effects within a single restorative system. Interpretative Perspective: Despite these advances, most available evidence derives from in vitro and preclinical studies, with significant heterogeneity across experimental models, evaluation methods, and outcome variables. This variability limits direct comparisons between studies and necessitates a cautious interpretation of claims regarding long-term antibacterial efficacy, functional tissue regeneration, and routine clinical applicability.

Conclusions: Antibacterial and bioregenerative nanomaterials represent a relevant and continuously evolving research direction in restorative dentistry. Their successful clinical translation will depend on establishing standardized testing protocols, conducting comprehensive safety assessments, and generating clinically relevant evidence supporting long-term efficacy and biological compatibility. Their successful clinical translation will depend on establishing standardized testing protocols, conducting comprehensive safety assessments, and generating clinically relevant evidence supporting long-term efficacy and biological compatibility.