Search Results (60)

Bruxism-induced wear and microbial colonization of oral splints remain significant challenges in restorative dentistry. In this study, we developed a series of antibacterial nanocomposites based on a poly(ethylene terephthalate-co-1,4-cyclohexanedimethylene terephthalate) (PET-G) matrix incorporated with zinc oxide (ZnO) particles (3, 7, and 10 wt%), designed for the next generation of oral appliances. The composites were fabricated via a solvent-casting method followed by thermal processing. Differential scanning calorimetry (DSC) revealed that the amorphous nature and glass transition temperature (Tg ≈ 80 °C) of the PET-G matrix remained stable, ensuring excellent processability. While a minor decrease in Shore D hardness and flexural strength (up to 15%) was observed due to filler-induced structural discontinuity, the mechanical integrity remained within clinically acceptable limits. Crucially, the PET-G/ZnO composites exhibited potent antimicrobial activity; the 7 and 10 wt% loadings achieved a 100% reduction in Streptococcus oralis viability and significant inhibition of Candida albicans. These findings demonstrate that ZnO integration provides a dual-functional advantage—maintaining the thermoplastic versatility of PET-G while introducing critical bioactive properties, positioning these materials as a superior alternative for effective long-term bruxism therapy. Full article

Polyhydroxyalkanoates (PHAs) are bio-based, biodegradable polyesters increasingly explored as sustainable biomaterials for regenerative medicine. This review summarizes recent advances in PHA-based bone substitute materials, highlighting their properties, fabrication methods, and biological performance. PHAs combine biocompatibility, tunable mechanical behavior, and degradation into non-toxic metabolites, while copolymerization and monomer selection modulate the stiffness, crystallinity, and resorption rate. Processing techniques such as solvent casting, electrospinning, and additive manufacturing allow the production of porous architectures that mimic bone extracellular matrix. Electrospinning is particularly suitable for nanoscale fibrous matrices, whereas 3D printing enables patient-specific scaffolds with controlled geometry and interconnected porosity. Scaffold performance can be further improved through the incorporation of osteoconductive fillers, including hydroxyapatite, β-tricalcium phosphate, bioactive glasses, graphene oxide, and carbon nanotubes, as well as through drug-delivery and pro-angiogenic functionalization. In vitro and in vivo studies consistently report favorable cytocompatibility, enhanced osteogenic differentiation, vascularization, and effective repair of bone defects in animal models. However, clinical translation remains limited by production costs, variability in polymer quality, thermal processing constraints, and regulatory challenges. Future progress will rely on more efficient biosynthesis, medical-grade purification, multifunctional scaffold design, and stronger collaboration between academia, industry, and clinicians to unlock the full potential of PHAs in regenerative bone therapies. Full article

Polymerization shrinkage remains a primary cause of marginal failure in posterior composite restorations, contributing to interfacial gap formation and secondary caries development. Bioactive filler technologies represent a paradigm shift, offering simultaneous stress reduction and therapeutic ion release through engineered matrix–filler interactions. This narrative review synthesizes current evidence on how bioactive glass (including 45S5), amorphous calcium phosphate, and surface pre-reacted glass-ionomer fillers modulate polymerization shrinkage dynamics and mechanical performance in bulk-fill systems. These systems exhibit distinct mechanisms of bioactivity, with bioactive glass (45S5) promoting ion release and apatite formation, amorphous calcium phosphate (ACP) enabling rapid calcium phosphate ion delivery for remineralization, and surface pre-reacted glass-ionomer (S-PRG) fillers providing sustained multi-ion release with buffering and antibacterial potential. A comprehensive literature search was conducted in PubMed/MEDLINE, Scopus, and Web of Science for studies published up to June 2025, including experimental investigations and reviews assessing bioactive filler integration, with studies selected based on predefined inclusion and exclusion criteria focusing on relevance and reported outcomes. The available evidence indicates that optimized bioactive formulations reduce shrinkage stress by approximately 25–40%, decreasing from 35–40 MPa in conventional systems to 22–32 MPa in bioactive bulk-fill composites while maintaining flexural strength above 100 MPa and elastic modulus within clinically acceptable ranges (11–13 GPa). However, substantial heterogeneity in filler chemistry, loading protocols, and testing methodologies limits cross-study comparisons. This variability also reflects differences in testing conditions, material compositions, and evaluation protocols across studies. Full article

The development of biodegradable scaffolds for load-bearing bone tissue engineering (BTE) presents a fundamental multi-criteria optimization challenge, requiring a simultaneous balance among mechanical performance, biological integration, and degradation kinetics. These criteria are inherently conflicting: composite formulations with the highest compressive strength frequently exhibit suboptimal porosity, while those with superior osteoconductivity often lack sufficient load-bearing capacity. To address this challenge rigorously, this study establishes a hybrid Fuzzy Analytic Hierarchy Process–Technique for Order of Preference by Similarity to Ideal Solution (Fuzzy AHP-TOPSIS) framework to evaluate and rank five clinically relevant biodegradable polymer–ceramic composite candidates: PLA/Hydroxyapatite (PLA/HA), PCL/Hydroxyapatite (PCL/HA), PLGA/Bioactive Glass (PLGA/BG), PLA/Carbon Nanotubes (PLA/CNT), and PLA/Magnesium (PLA/Mg). Quantitative property data were systematically extracted from ten peer-reviewed experimental studies published between 2021 and 2025, and converted into Triangular Fuzzy Numbers (TFNs) to explicitly model inter-study variability arising from differences in fabrication methods, filler loading, and testing conditions. Fuzzy AHP analysis identified Compressive Strength (w = 25.2%) and Cell Viability (w = 21.5%) as the dominant decision criteria for load-bearing cortical bone repair. The Fuzzy TOPSIS ranking identified PLA/HA as the optimal composite candidate (Closeness Coefficient, CCᵢ = 0.677), demonstrating the superior multi-criteria balance required for cortical bone repair applications. Although PLA/CNT achieved the highest mechanical strength, it was outranked due to lower osteoconductivity and elevated cytotoxicity uncertainty at high nanotube concentrations (CCᵢ = 0.544). Sensitivity analysis across five distinct weighting scenarios confirmed the robustness of PLA/HA as the primary candidate. These findings provide a validated, replicable computational blueprint for evidence-based scaffold material selection, with direct implications for reducing the burden of costly trial-and-error experimentation in BTE research. Full article

With the growing clinical use of ion-releasing resin composites, their repairability has become an important consideration in minimally invasive restorative dentistry. Therefore, this study investigated the repair bond strength of a universal composite restorative to commercially available and experimental ion-releasing resin composite materials. Specimens (n = 8 per group) were produced from three commercially available ion-releasing composite materials (ACTIVA BioACTIVE-RESTORATIVE, Cention Forte, Beautifil II), one experimental ion-releasing resin composite containing 20 wt% bioactive glass fillers, and two conventional resin composites (3M Filtek Supreme XTE, Ceram.x Spectra ST), and aged by thermal cycling in artificial saliva (5000 cycles, 5–55 °C). Substrate surfaces were sandblasted (Al₂O₃, 50 µm), silanized (Monobond Plus), and repaired using adhesive (OptiBond FL) and universal resin composite (Ceram.x Spectra ST). After further thermal cycling, micro-tensile repair bond strength was assessed and analyzed using one-way ANOVA followed by Tukey’s post hoc test. Failure modes were determined by stereomicroscopy (25× magnification) and statistically compared among the groups. Highest mean repair bond strength values were obtained for ACTIVA BioACTIVE-RESTORATIVE, Beautifil II, and 3M Filtek Supreme XTE (53.8, 46.2, and 43.0 MPa, respectively), which did not differ significantly among each other. ACTIVA BioACTIVE-RESTORATIVE attained significantly higher bond strength than the experimental composite, Ceram.x Spectra ST, and Cention Forte, and showed the highest incidence of cohesive failures (40%). No significant bond strength differences were detected among Beautifil II, 3M Filtek Supreme XTE, experimental composite, Ceram.x Spectra ST, and Cention Forte (36.2–46.2 MPa). In conclusion, ion-releasing resin composites can be repaired with conventional universal composite and show repair bond strength values at least as high as those of conventional composite materials. Full article

Insufficient osteogenic activity and mechanical properties of poly-L-lactic acid (PLLA) are urgent problems to be solved in deepening their application in bone tissue engineering. In this work, PLLA/mesoporous bioactive glass (PLLA/MBG) scaffolds and PLLA/simvastatin-loaded mesoporous bioactive glass (PLLA/MBG@SIM) scaffolds with filler content of 5, 10, and 15 wt% MBG and MBG@SIM were fabricated via electrospinning technology. At 10 wt% MBG loading, the tensile strength and tensile modulus were 3.23 ± 0.26 MPa and 124.47 ± 8.68 MPa, respectively, over 50% higher than those of PLLA scaffolds, demonstrating a significant enhancement in mechanical properties. Moreover, the incorporation of MBG improved the bioactivity of the PLLA scaffold, promoting the formation of apatite on the surface of the scaffolds. All composite scaffolds were non-toxic with good biocompatibility. Furthermore, PLLA/MBG@SIM composite scaffolds displayed superior osteogenic effects, better than the pure PLLA scaffolds and PLLA/MBG scaffolds. This work presents a multifunctional scaffold system combining enhanced mechanical strength with potent osteogenic activity, showing great promise for bone tissue engineering applications. Full article

Zeolites are becoming potentially important multifunctional fillers in dentistry, providing a distinctive blend of mechanical reinforcement, remineralization, and antimicrobial properties. Their crystalline aluminosilicate frameworks offer ion-exchange capacity, the controlled release of therapeutic ions (Ag⁺, Zn²⁺, Ca²⁺, Sr²⁺, Cu²⁺), and compatibility with various dental composites. Sustainable and cost-effective zeolite production has become possible due to recent developments in synthetic strategies. These include the valorization of industrial and agricultural residues that are abundant in Si and Al. The incorporation of zeolites into dental adhesives, restorative composites, glass ionomer cements, root canal sealers, prosthetic materials, and implant coatings has been shown to improve mechanical stability and remineralization potential, and enhance antibacterial protection. The unique advantage of zeolites in integrating multifunctionality within a single system is emphasized when compared with other fillers, such as hydroxyapatite nanoparticles and bioactive glass. Nevertheless, obstacles persist with respect to clinical validation, regulatory pathways, and long-term biocompatibility. This review critically assesses the structure–function relationships, synthesis strategies, and dental applications of zeolites, while also delineating future perspectives for their translation into clinically approved, sustainable dental biomaterials. Full article

The long-term success of composite restorations largely depends on the performance of dental adhesives at the adhesive–tooth interface. Despite ongoing improvements, secondary caries remains the leading cause of restoration failure, primarily due to the adhesive layer’s susceptibility to hydrolytic degradation, bacterial invasion, and limited biological functionality. This review provides a comprehensive overview of recent advances in bioactive dental adhesives for preventing recurrent caries, focusing on their mechanisms of action, material performance, therapeutic functions, and clinical potential. Bioactive adhesives combine durable bonding with biofunctional benefits, including remineralization, antimicrobial activity, enzymatic inhibition, and support for tissue regeneration. By integrating these properties, they enhance both the durability of the adhesive interface and oral health. Recent strategies include the incorporation of ion-releasing fillers such as calcium phosphate and bioactive glass, antimicrobial monomers such as MDPB and quaternary ammonium methacrylates, enzymatic inhibitors, and hydrolytically stable resin matrices. Together, these components strengthen the adhesive interface and provide biologically active effects to prevent recurrent caries. Although in vitro findings are promising, challenges remain, including limited long-term clinical data, the absence of standardized evaluation protocols, and barriers to clinical translation. Addressing these gaps is essential to ensure predictable clinical outcomes. Bioactive dental adhesives represent a paradigm shift in restorative dentistry, evolving from passive bonding agents to multifunctional therapeutic materials. By combining structural durability with biological protection, they hold significant potential to prevent recurrent caries and improve the long-term success of composite restorations. 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

In this work, the electrospinning technique was used to prepare novel polymeric composite fibers containing Te-doped bioactive glass powders. Bioactive glass powders containing tellurium (STe5 glass) were chosen as fillers for the composites, owing to their bioactive, antibacterial, and antioxidant properties. The biopolymer poly (ϵ-caprolactone) (PCL) and acetic acid (AA) were used as raw materials for the preparation of the polymeric matrix. FESEM analysis confirmed a good incorporation of the glass powders in the polymeric fibers, of up to 20% by weight. Wettability, mechanical, in vitro stability and preliminary antibacterial tests were also performed. The results showed that the treatment in AA did not affect the bioactivity of the glass powders, the presence of STe5 powders in PCL enhanced the wettability of the fibers, and mechanical properties improved by increasing the amount of STe5 powders, as well as the antibacterial effect. Therefore, the obtained materials appear promising for developing multifunctional composite materials for applications in tissue engineering. Full article

This study examined the degree of monomer conversion (DC) and mechanical properties of experimental orthodontic adhesives containing monocalcium phosphate monohydrate (MCPM), Sr-bioactive glass (Sr-BAG) nanoparticles, and andrographolide. Experimental adhesives were prepared with a 4:1 powder-to-liquid ratio, containing methacrylate monomers with varying formulations of glass fillers and additives. DC was measured using ATR-FTIR (n = 5) with and without bracket placement under two curing protocols: conventional LED (1200 mW/cm², 20 s) and high-intensity LED (3200 mW/cm², 3 s). The biaxial flexural strength and modulus were tested after 4-week water immersion (n = 8). Transbond XT was used as the commercial comparison. Transbond XT exhibited higher DC (33–38%) than the experimental materials. Conventional LED curing produced higher DC than high-intensity LED, while bracket placement reduced DC by approximately 10% in the experimental materials but minimally affected Transbond XT. Transbond XT demonstrated a superior biaxial flexural strength (188 MPa) compared to the experimental adhesives (106–166 MPa, p < 0.05). However, the experimental formulations with low additive concentrations showed a comparable biaxial flexural modulus (5.0–5.5 GPa) to Transbond XT (5.6 GPa) (p > 0.05). Although the experimental adhesives exhibited lower DC and strength than the commercial product, their values still met the ISO standards, suggesting their potential clinical viability despite their modified compositions. Full article

Objective: To evaluate the surface micromorphology of bioactive glass-modified resin composite materials after storage in simulated body fluid for different periods of time and ultrasonic cleaning. Materials and methods: A resin composite material (Heliomolar Flow, Ivoclar Vivadent) was modified by incorporating 10 or 20 wt% of bioactive glass 45S5. The unmodified conventional composite (0 wt% bioactive glass) served as the control. Surface morphology of light-cured composite specimens was examined by profilometry both before and after storage in simulated body fluid (SBF; pH = 7.4, t = 37 °C) for 0, 3, 7, or 30 days, and surface roughness (Ra) was recorded. After storage, ultrasonic cleaning (UC) of the specimens was performed for 10 min in an ultrasonic bath filled with deionized water, and the profilometric measurements were subsequently repeated. In addition, the surfaces of specimens were examined by scanning electron microscopy (SEM). Results: Directly after specimen preparation, the Ra values of the composites modified with bioactive glass were similar to those of the conventional composite (0 wt% bioactive glass). A longer immersion in SBF and higher added concentrations of bioactive glass led to an increase in surface roughness. SEM examination revealed that precipitates were formed on the surfaces of specimens containing bioactive glass after exposure to SBF for at least 7 days. The density of these precipitates increased with exposure time and added bioactive glass content. After subsequent ultrasonic cleaning, a significant Ra reduction was observed for specimens containing 10 and 20 wt% bioactive glass and stored for 30 days (p < 0.001). For the resin composite material doped with 20 wt% bioactive glass particles, UC revealed a significant Ra reduction at all time points. Conclusion: The increase in the surface roughness of bioactive glass-modified composites after storage in SBF might be partly attributed to precipitate formation on their surfaces. After ultrasonic cleaning, surface roughness was still increased, indicating poorer surface quality compared to conventional composite. Full article

In this study, the microinjection molding technology was adopted to prepare polylactic acid (PLA)/polycaprolactone (PCL)/bioactive glass (BG) composites with varying BG contents for biomedical applications. The various measurement techniques, including scanning electronic microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, the water contact angle (WCA) test, the mechanical test, and in vitro biological evaluations, were applied to characterize the above interesting biocomposites. The experimental results show that the extremely strong shear force field generated during the microinjection molding process could induce the in situ formation of micron PCL dispersed phase fibril structures and strongly promote the homogeneous dispersion of micron BG filler particles in the PLA/PCL polymer matrix, which therefore leads to a significant improvement in the specific mechanical property of the PLA/PCL/BG composite. For example, with BG fillers content increasing to 10 wt%, the Young’s modulus of the above obtained PLA/PCL/BG composite could reach 2122.9 MPa, which is 1.47 times higher than that of the unfilled PLA/PCL blend material. In addition, it is also found that under the simulated body fluid (SBF) environment, the incorporated BG fillers in the PLA/PCL polymer matrix could be effectively transformed into hydroxyapatite (HA) components on the treated sample surface, thus being greatly advantageous to enhancing the material’s in vitro bioactivity. Obviously, the microinjection molded PLA/PCL/BG biocomposites could exhibit excellent comprehensive performance, revealing that the microinjection molding processing method could hold great potential in industrialization applications of the resulting biodegradable biomedical materials. Full article

This study investigated the effects of resin composites (RCs) containing surface pre-reacted glass ionomer (S-PRG) filler on the dentin microtensile bond strength (μTBS) of HEMA-free and HEMA-containing universal adhesives (UAs). Water sorption (WS) and solubility (SL), degree of conversion (DC), and ion release were measured. The UAs BeautiBond Xtreme (BBX; 0% HEMA), Modified Adhesive-1 (E-BBX1; 5% HEMA), Modified Adhesive-2 (E-BBX2; 10% HEMA), and two 2-step self-etch adhesives (2-SEAs): FL-BOND II (FBII; with S-PRG filler) and silica-containing adhesive (E-FBII) were used. Teeth were restored with Beautifil Flow Plus F00 with S-PRG filler (BFP) and flowable resin composite with silica filler (E-BFP). μTBS was evaluated after 24 h and 6 months of water storage. WS and SL measurement followed ISO 4049:2019; spectroscopy measured DC; ICP-MS evaluated ion release. BBX and FBII presented the highest DC. The adhesives did not comply with the WS ISO requirements, but the bonding resin of 2-SEAs complied with the SL threshold. BFP released more ions than E-BFP. BFP positively affected the μTBS of UAs, regardless of HEMA concentration after 24 h, comparable to the 2-SEAs. The 6 months μTBS decrease depended on the adhesive and RC combination. HEMA did not affect the μTBS of UAs, while bioactive resins had a positive impact. Full article

The treatment of damaged enamel surfaces involves modification of the enamel surface with artificial materials or the development of a pseudo-enamel, with research focusing on bioactive and biomimetic materials. In this study, a bioactive auto-polymerizing resin (APR) was developed by adding surface-pre-reacted glass ionomer (S-PRG) fillers of different quantities to APR. Its bioactive effects were evaluated via pH neutralization, ion release, and inhibition of enamel demineralization studies. The pH and fluoride ion release were measured using ion-specific electrodes, revealing that the APR disk with the S-PRG filler immediately neutralized the lactic acid solution (pH 4.0) through ion release. Inductively coupled plasma atomic emission spectrometry revealed that the Sr ion release peaked on the first day, with the other ions following the order F > B > Si > Al > Na, exhibiting a weekly decrease in the same order. Scanning electron microscopy was used to examine the enamel block morphology of the disks after 7 d of incubation, revealing enamel demineralization in disks without the S-PRG filler, whereas no demineralization occurred in disks with the S-PRG filler. APR containing the S-PRG filler demonstrated acid buffering suppressed enamel demineralization and bioactive properties. Full article