Objective: To investigate the barrier membrane fixation performance and enhanced guided bone regeneration (GBR) capability of a thermosensitive adhesive containing bioactive glass nanoparticles in order to provide a novel solution for membrane fixation during GBR procedures. Methods: M2NP@BGN (methoxyethyl acrylate-co-N-isopropylacrylamide-co-protocatechuic acid@Bioactive glass nanoparticle), a thermosensitive adhesive, was synthesized via free radical polymerization by compositing methoxyethyl acrylate, N-isopropylacrylamide, and protocatechuic acid into a basic adhesive that was modified with bioactive glass nanoparticle (BGN). The successful fabrication of basic adhesive M2NP was characterized by attenuated total reflection-Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The thermosensitive adhesive M2NP@BGN (BGN concentration of 1 mg/mL) was characterized by scanning electron microscopy and a rheometer. By adjusting the BGN concentration (0.1 mg/mL, 0.5 mg/mL, 1 mg/mL, and 2 mg/mL), the adhesive and mechanical strengths were investigated with a universal testing machine. Biocompatibility was evaluated with a cell counting kit-8 assay and hemolysis test to identify the optimal formulation. The optimal material’s extract was co-cultured with mouse bone marrow mesenchymal stem cells, and its osteogenic activity was examined in vitro by quantitative real-time PCR, alkaline phosphatase, and alizarin red S staining. The rat mandibular defect model was established, filled with bone graft, and divided into 3 groups based on membrane fixation method: M2NP@BGN (BGN concentration of 1 mg/mL) fixation group (M2NP@BGN), titanium nail fixation group (Nail), and unfixed control group (Negative). Bone regeneration was analyzed after 8 weeks by micro computed tomography and histological staining. Results: M2NP@BGN (BGN concentration of 1 mg/mL) was successfully synthesized and demonstrated rapid gelation under warm, humid conditions. The adhesive with a BGN concentration of 1 mg/mL exhibited the highest adhesive strength (P < 0.001) and significantly enhanced mechanical strength (P < 0.001) under 37℃ wet conditions. All formulations showed excellent biocompatibility, with cell viability > 80% and hemolysis ratio < 5%. M2NP@BGN (BGN concentration of 1 mg/mL) significantly upregulated the expression of Runx2 and Col I (P < 0.001) and enhanced the activity of osteogenic differentiation markers (P < 0.05). In the animal model, the M2NP@BGN group (BGN concentration of 1 mg/mL) achieved significantly higher bone volume fraction and better bone maturity compared to the negative and nail groups (P < 0.05). Conclusion M2NP@BGN (BGN concentration of 1 mg/mL) combines excellent wet adhesion with potent osteogenic activity, enhances the bone augmentation efficacy of membranes, and presents a novel fixation strategy with significant clinical translation potential for GBR therapy.

Hypoxemia is a common pathological state characterized by low oxygen saturation in the blood. This condition compromises mucosal barrier integrity particularly in the gut and oral cavity. However, the mechanisms underlying this association remain unclear. This study used periodontitis as a model to investigate the role of platelet activation in oral mucosal immunopathology under hypoxic conditions. Hypoxia upregulated methyltransferase-like protein 4 (METTL4) expression in platelets, resulting in N⁶-methyladenine modification of mitochondrial DNA (mtDNA). This modification impaired mitochondrial transcriptional factor A-dependent cytosolic mtDNA degradation, leading to cytosolic mtDNA accumulation. Excess cytosolic mt-DNA aberrantly activated the cGAS-STING pathway in platelets. This resulted in excessive platelet activation and neutrophil extracellular trap formation that ultimately exacerbated periodontitis. Targeting platelet METTL4 and its downstream pathways offers a potential strategy for managing oral mucosa immunopathology. Further research is needed to examine its broader implications for mucosal inflammation under hypoxic conditions.
DNA, Mitochondrial/metabolism* ; Mouth Mucosa/pathology* ; Hypoxia/immunology* ; Methyltransferases/metabolism* ; Blood Platelets/metabolism* ; Animals ; Periodontitis/immunology* ; Humans ; Platelet Activation ; Mice

The colonization of microorganisms planted on the surface of teeth and restoration materials is the main cause of oral disease and treatment failure. How to improve the antibacterial properties of dental materials is a hot topic in dentistry. Nano-sized antibacterial materials have attracted much attention. Among them, metal and metal oxide nanoparticles are prominent due to their strong and broad-spectrum antibacterial activity. Thus, in recent years, many studies have used metal and metal oxide nanoparticles to develop antimicrobial dental materials for resin restoration, root canal therapy, orthodontic treatment, and implant surface and removable denture repair and have found that the antibacterial properties of nano-sized materials are significantly enhanced. However, the mechanical properties and esthetic properties of the modified materials are affected, so it is still necessary to explore appropriate modification methods. In addition, most of the experiments are carried out in vitro, which cannot accurately simulate the oral environment. Therefore, the antibacterial effect, cytotoxicity and immune response of these materials in vivo still need further research and exploration. This paper reviewed the potential antibacterial mechanisms and the safety of those nanoparticles and their applications in dentistry.

A rapid, sensitive and simple liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for the simultaneous determination of yogliptin and its metabolite in Wistar rat plasma. Linagliptin and dexamethasone were chosen as the internal standards of yogliptin and its metabolite, (R)-8-(3-hydroxypiperidine- -yl)-7-(but-2-yn-1-yl)-1-((5-fluorobenzo[d]thiazol-2-yl)methyl)-3-methyl- H-purine-2, 6 (3H, 7H)-dione, respectively. After a simple protein precipitation using acetonitrile as the precipitating solvent, both analytes and ISs were separated on a Grace Altima HP C18 column (2.1 mm x 50 mm, 5 microm) with gradient elution using methanol (containing 0.1% formic acid, 4 mmol x L(-1) ammonium acetate)-0.1% formic acid (containing 4 mmol x L(-1) ammonium acetate) as the mobile phase. A chromatographic total run time of 4.4 min was achieved. Mass spectrometric detection was conducted with electrospray ionization under positive-ion and multiple-reaction monitoring modes. Linear calibration curves for yogliptin and its metabolite were over the concentration range of 0.5 to 500 ng x mL(-1) with a lower limit of quantification of 0.5 ng x mL(-1). The intra- and inter- assay precisions were all below 14%, the accuracies were all in standard ranges. The method was used to determine the concentration of yogliptin and M1 in Wistar rat plasma after a single oral administration of yogliptin (27 mg x kg(-1)). The method was proved to be selective, sensitive and suitable for pharmacokinetic study of yogliptin and M1 in Wistar rat plasma.