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Background: Postoperative wound sealing and localized drug delivery are critical needs in nasopharyngeal carcinoma (NPC) management. Natural polysaccharide-based films offer a biocompatible platform for addressing these challenges. Methods: A composite film was prepared by Schiff base crosslinking of chitosan and oxidized pullulan. The film was characterized by FTIR, and its adhesion, drug release, cytocompatibility, and effects on cell migration were evaluated using in vitro assays. Results: The composite film exhibited a distinct C=N peak in FTIR spectra and significantly enhanced wet adhesion (55 kPa) compared to individual components. Cisplatin-loaded films showed sustained release over 72 h and reduced the viability of CNE-2 cells to 28%. The drug-free film was non-cytotoxic. Extracts from the composite film promoted nasopharyngeal epithelial cell migration, as shown by RTCA assay. Conclusion: This study explored the in vitro characteristics of a chitosan/oxidized pullulan film and evaluated its basic biological performance at the cellular level capable of localized drug release and supporting cell-level healing responses. Further validation in more complex models is warranted.

Background: Gastric cancer remains one of the leading causes of cancer-related deaths worldwide, and the development of effective, targeted drug delivery systems is crucial to improve therapeutic outcomes. Graphene oxide (GO)-based nanocarriers have shown promise for controlled drug release, yet their biological evaluation remains limited. Methods: We synthesized a composite nanoparticle system by electrostatic self-assembly of chitosan (CS) onto graphene oxide (GO), followed by doxorubicin (DOX) loading. The resulting GO–CS–DOX nanoparticles were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), zeta potential, and pHresponsive release profiles. Preliminary biological performance was evaluated in gastric cancer cells (AGS), including dose–response cytotoxicity and fluorescence-based uptake studies. Results: GO–CS– DOX nanoparticles showed a clear pH-dependent DOX release behavior, with accelerated release under mildly acidic conditions. DLS and zeta potential measurements confirmed successful drug loading and changes in surface charge. In vitro, GO–CS–DOX demonstrated comparable or slightly enhanced cytotoxicity relative to free DOX at specific concentrations. Cellular uptake of DOX was observed under acidic conditions, consistent with lysosomal trafficking. However, only preliminary in vitro data were collected and no mechanistic apoptosis studies were performed. Conclusion: This study presents the design and initial evaluation of a pH-responsive GO–CS–DOX nanocarrier. While the in vitro results indicate potential for controlled drug release and tumor-targeted delivery, the biological findings are still limited and should be interpreted as preliminary. Further in-depth studies, including apoptosis assays and in vivo validation, are necessary to fully establish therapeutic efficacy.

This in vitro study performed a comparative mechanical evaluation of three classes of direct restorative materials: resin composites, polyacid-modified composite resins (components), and Glass Ionomer Cements (GICs). The objective was to clarify the mechanical position of components relative to composites and glass ionomer cements (GICs). Specimens from two materials per class including the components Dyract AP and Dyract Extra were fabricated using standardized molds. Compressive, diametral tensile, and three-point flexural strength tests were conducted according to ADA and ISO specifications, followed by statistical analysis using ANOVA and Tukey’s HSD test. Results established a consistent mechanical hierarchy: composite resins exhibited the highest strength values in all tests, followed by components, with GICs demonstrating the lowest. Within the component group, the thirdgeneration Dyract Extra showed superior properties compared to Dyract AP. The findings confirm that components occupy an intermediate mechanical position, offering significantly greater strength than GICs but not matching composites. Thus, components suit low-to-moderate stress applications where fluoride release and handling ease are beneficial, while composites remain indicated for high-stress areas. This study provides clear evidence for evidence-based clinical material selection.

Objective: This study aimed to investigate the effect of microabrasion, bleaching, and resin infiltration (RI) on the color and gloss of stained remineralized caries-like lesions (s-RCL). Materials and methods: Human enamel specimens were demineralized and then randomly assigned to seven groups (n = 12). G1; no treatment, G2; RI, G3; remineralized and stained to create s-RCLs, G4; s- RCLs + at-home bleaching protocol (AHB) (15% carbamide peroxide, 4 h/d × 7); G5; s-RCLs + microabrasion (6.6% hydrochloric acid, 1 min/3 cycles) + AHB; G6; s-RCLs + AHB + RI; G7: s-RCLs + microabrasion + AHB+ RI. Color and gloss were measured at baseline, after demineralization, and after the treatments. Outcomes were analyzed using ANOVA followed by Tukey’s test (α =0.05). Results: The mean color change after demineralization and staining (except in G1 and G2) was significant (p < 0.0001), indicating the creation of white spot lesions and s-RCLs, respectively. Treatment improved the color in G2, but not significantly. Groups 4–7 showed improvement (p < 0.01) yet did not exceed the staining values. Gloss decreased (p < 0.0001) after staining in all groups except in G1 and G2, compared to demineralization, with no significant difference among groups. Treatments significantly increased (p < 0.0001) gloss, except in the controls (G1 and G3), where G7 had the highest value and G4 had the lowest. Conclusion: The combination of microabrasion, AHB, and RI has demonstrated significant potential in improving the gloss and an average efficacy in partially improving the color outcome of s-RCL.

The present study assesses the surface roughness (SR) and microhardness (Vickers Hardness Number, VHN) of novel resin-filled ceramic and resin composite materials fabricated using 3D printers and CAD/CAM technologies after being subjected to thermal cycling. Permanent resin restorations were fabricated using 3D printers (C; Saremco Print Crowntec, F; Permanent Crown Resin Formlabs, B VarseoSmile Crown Plus Bego) and resin-containing CAD/CAM permanent restorative materials (E; Vita Enamic, Vita, U; 3M Lava Ultimate), with a total of 75 rectangular specimens produced (12 × 14 × 1.5 mm) (n = 15). The SR (Ra, Rz) and MH values of the materials were measured before and after thermal aging, and scanning electron microscopy (SEM) images were obtained following thermal cycling. The dataset obtained from the study was evaluated with a Two-Way Analysis of Variance (Twoway ANOVA) (α = 0.05). There was a broad and statistically significant difference in the SR values of all groups before and after thermal ageing (p < 0.001). In the MH intergroup comparisons, the values of the groups before and after the ageing process were found to be statistically significant (p < 0.001). The highest Ra values were recorded in 3D printed resins, while the lowest values were observed in CAD/CAM-produced materials. Furthermore, the number of samples produced using 3D printers was lower than that produced by CAD/CAM.

Background: Postoperative recurrence remains a major challenge in colorectal cancer due to residual tumor cells that survive surgical resection. Systemic chemotherapy is often insufficient for complete local control and causes systemic toxicity. Combining local chemotherapy with gene silencing may offer a more effective and targeted strategy. Methods: We developed PLGA-based nanoparticles co-loaded with irinotecan and Bcl-2-targeting siRNA. The nanoparticles were characterized for morphology, encapsulation efficiency, release kinetics, cellular uptake, cytotoxicity, gene silencing efficiency, and in vivo efficacy using a murine tumor resection model. Results: The dual-loaded nanoparticles exhibited uniform spherical morphology, high encapsulation efficiencies (82.3% for irinotecan and 69.5% for siRNA), and sustained release of both agents. Conclusion: This localized combinatorial delivery system provides a synergistic approach for eliminating residual tumor cells and preventing recurrence after colorectal cancer surgery, demonstrating high therapeutic potential and translational value.

Objective: To evaluate the clinical efficacy of chitosan/alginate (CS/Alg) double-network hydrogels in the repair of temporomandibular joint (TMJ) disc defects and to investigate the underlying mechanisms. Methods: A prospective randomized controlled trial was conducted, including 104 patients with irreducible anterior disc displacement or disc perforation of the TMJ who were treated at the Department of Oral and Maxillofacial Surgery between January 2023 and December 2023. Patients were randomly divided into an experimental group (CS/Alg double-network hydrogel implantation, n = 53) and a control group (conventional disc repair or discectomy, n = 51). Randomization was performed using computer-generated random number tables with allocation concealment. Primary outcome measures included maximum interincisal opening (MIO), pain visual analog scale (VAS) scores, and TMJ functional index. Secondary outcome measures included imaging findings, complication rates, and patient satisfaction. Follow-up evaluations were conducted at baseline, 1 months, 3 months, 6 months, and 12 months postoperatively. Results: A total of 96 patients completed the 12-month follow-up (experimental group: 50 patients; control group: 46 patients). No significant differences were observed in baseline characteristics between the two groups (p > 0.05). At 12 months postoperatively, the experimental group demonstrated significantly greater improvement in MIO compared to the control group (13.8± 4.6 mm vs. 7.9 ± 4.3 mm, p < 0.001). The reduction in VAS pain scores was superior in the experimental group compared to the control group (5.4 ± 1.3 vs. 3.8 ± 1.6, p < 0.001). The experimental group achieved higher TMJ functional index scores (82.4 ± 11.2 vs. 71.3 ± 13.6, p < 0.001) and higher treatment success rates (94.0% vs. 78.3%, p = 0.021). Imaging evaluation revealed better preservation of disc position and joint space in the experimental group (p < 0.05). The overall complication rate was significantly lower in the experimental group compared to the control group (20.8% vs. 62.7%, p < 0.001). Multivariable analysis identified CS/Alg double-network hydrogel treatment as an independent protective factor for treatment success (OR = 3.58, 95% CI: 1.42–9.03, p = 0.007). Histological analysis demonstrated good biocompatibility and fibrocartilaginous tissue regeneration. Conclusion: CS/Alg double-network hydrogels exhibit excellent clinical efficacy and safety in TMJ disc repair. Through multiple mechanisms, including providing appropriate mechanical support, modulating the immune microenvironment, and promoting extracellular matrix remodeling, this material significantly improves joint function and patient quality of life, offering a novel and effective therapeutic strategy for TMJ disorders.

Fused deposition modeling (FDM) is increasingly used to manufacture functional polymer components, but the mechanical performance of printed parts is strongly influenced by process parameters. This study examines the effects of build orientation, infill density, infill pattern, and printing speed on the tensile behavior of polylactic acid (PLA) specimens. Dog-bone samples with ISO 527-2 type 1A geometry were printed using three build orientations (A—horizontal, B—vertical, C—lateral), two infill densities (40% and 70%), two infill patterns (triangle and tri-hexagon), and two printing speeds (40 and 60 mm/s). Tensile tests were performed to determine Young’s modulus, yield stress, ultimate tensile strength, and elongation at break. The lateral (C) orientation provided the highest mechanical performance, with an average ultimate tensile strength of 47 MPa and a Young’s modulus of 2.9 GPa, compared to 33 MPa (E ≈ 2.4 GPa) for the horizontal (A) orientation and 16 MPa (E ≈ 2.0 GPa) for the vertical (B) orientation. For horizontally printed specimens, a 70% infill consistently increased tensile strength relative to 40% infill. The combination of 70% infill, triangular pattern, and 40 mm/s printing speed (A70T40) achieved the highest ultimate tensile strength among the infill configurations. These findings highlight the importance of selecting appropriate printing parameters when PLA components are intended for load-bearing applications.

Background: Postoperative recurrence of glioblastoma is driven by residual tumor cells at the resection margins. Conventional systemic chemotherapy is limited by poor brain penetration and systemic toxicity. Methods: We developed an injectable thermoresponsive hydrogel for localized delivery of cisplatin. The hydrogel undergoes sol–gel transition at body temperature, forming an in situ drug depot. Physicochemical properties, in vitro release, cytotoxicity, and cellular platinum uptake were evaluated. Results: The hydrogel exhibited a porous structure and a sharp gelation near 37◦C. Drug release was temperature-dependent, with sustained release at physiological temperature. Cisplatin (CDDP)-loaded hydrogel significantly reduced glioma cell viability and achieved higher intracellular platinum accumulation compared to free drug. Conclusion: This thermoresponsive hydrogel enables injectable, localized cisplatin delivery with improved cellular uptake and cytotoxicity, offering a promising platform for preventing glioblastoma recurrence after surgery.

Background: Airway epithelial injury is common in respiratory diseases and post-surgical conditions, leading to impaired barrier function and delayed healing. There remains an urgent need for localized biomaterial-based therapies to support epithelial repair under oxidative stress. Methods: We developed a self-healing injectable hydrogel based on chitosan and oxidized dextran, crosslinked via dynamic imine bonds. N-acetylcysteine (NAC) was encapsulated as a therapeutic payload. The hydrogel was characterized for rheological recovery, drug release kinetics, and evaluated in vitro using airway epithelial cells. Results: The hydrogel exhibited excellent self-healing behavior and sustained NAC release over 48 h. It promoted cell proliferation, enhanced migration in scratch assays, and upregulated ZO-1 expression. In an H₂O₂-induced injury model, NAC-loaded hydrogels significantly restored cell viability to near-normal levels. Conclusion: This NAC-loaded self-healing hydrogel provides both mechanical and biochemical support for airway epithelial repair. It offers a minimally invasive platform for localized treatment of airway injuries, with potential applications in respiratory disease management and post-operative mucosal healing.