
Adenoid hypertrophy is one of the most common causes of upper airway obstruction in children, often presenting with nasal congestion as the initial symptom and accompanied by a series of related manifestations. Due to impaired nasal ventilation, affected children are forced into compensatory mouth breathing. This altered breathing pattern modifies the upper airway fluid environment, leading to abnormal changes in airflow velocity, pressure distribution, and flow patterns. Prolonged mouth breathing disrupts the dynamic equilibrium of perioral musculature, thereby interfering with normal maxillofacial growth and development and contributing to the occurrence of malocclusion. Upper airway fluid mechanics, developed through the integration of computational fluid dynamics (CFD) technology and medical imaging, serves as a quantitative analytical tool capable of precisely characterizing airflow velocity, pressure distribution, and flow patterns within anatomically complex structures such as the nasal cavity and pharynx. By leveraging multidimensional fluid mechanical parameters, this approach can accurately depict the flow field characteristics of the upper airway in patients with adenoid hypertrophy, clearly illustrating the relationship between airway anatomy and ventilatory function, and providing objective quantitative evidence for disease assessment. In clinical practice, CFD enables the evaluation of how different interventions improve airway ventilation, allowing scientific prediction and objective assessment of therapeutic outcomes. Nevertheless, several critical challenges remain, including the lack of standardized protocols for upper airway modeling and boundary condition definition, insufficient understanding of the dynamic relationship between fluid mechanical parameters and the progression of malocclusion severity, and the predominance of cross-sectional study designs with limited longitudinal data on pre- and post-intervention flow field changes, which restricts the translation of simulation results into actionable clinical indicators. In the future, with the establishment of standardized simulation workflows and the conduct of large-scale prospective cohort studies, upper airway fluid mechanics is expected to integrate with artificial intelligence and multimodal imaging technologies to develop intelligent decision-support systems, thereby advancing the scientific rigor and personalization of diagnosis and treatment for adenoid hypertrophy and associated malocclusion.
Mandibular condylar fractures are common injuries in oral and maxillofacial surgery. The unique anatomical structure and mechanical environment of the condyle render its fracture healing process distinct from that of long bones. Parathyroid hormone (PTH) and its active fragment PTH(1-34) (such as the drug teriparatide) are among the few clinically available agents with bone-anabolic properties, and have shown promise in fracture repair. However, the anatomical and mechanical discrepancies between the condyle and long bones raise doubts as to whether the efficacy of PTH observed in long bones can be directly extrapolated to condylar fractures. Elucidating how mechanical loading modulates the bone remodeling effects of PTH within the specific mechanical environment of the mandibular condyle thus constitutes a critical entry point for addressing this question. This review summarizes recent advances regarding how mechanical loading influences PTH-promoted healing of mandibular condylar fractures from three perspectives: the mechanical sensitivity of condylar fracture healing, the molecular mechanisms by which PTH regulates bone remodeling, and the synergy between mechanical and pharmacological interventions, with the aim of clarifying the existing molecular evidence for mechanical-PTH synergy derived from long-bone and in vitro models, and critically evaluating the feasibility and limitations of extrapolating these findings to condylar fractures. Evidence from long-bone fracture models and in vitro mechanical loading systems indicates that mechanical loading modulates the direction of PTH-mediated bone remodeling through the receptor activator of the nuclear factor-κB ligand (RANKL)/osteoprotegerin (OPG) axis and the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/glycogen synthase kinase-3β (GSK3β)/nuclear factor of the activated T-cells c1 (NFATc1) pathway, an effect that exhibits marked intensity- and time-dependent characteristics. Nevertheless, critical challenges remain in this field, including the standardization of quantitative mechanical loading parameters, the accumulation of direct evidence from condyle-specific fracture models, and the in-depth elucidation of the regulatory mechanisms governing mechanical-drug synergy. Future research should integrate finite element analysis, standardized mechanical loading techniques, and single-cell omics to establish a quantitative relationship between mechanical parameters, cellular responses, and PTH effects, thereby providing a theoretical basis for optimizing postoperative masticatory load management and PTH administration strategies in condylar fractures.
Objective To explore new therapeutic strategies for periodontitis, this study prepared extracellular vesicles (EVs) derived from human umbilical cord mesenchymal stem cells (hUC-MSCs) loaded with saikosaponin D (SSD) and evaluated their efficacy in a mouse model of periodontitis. Methods This study was approved by the Medical Ethics Committee and the Laboratory Animal Ethics Committee of the unit. hUC-MSCs at logarithmic growth phase were seeded into 96 well plates and then treated with various concentrations of SSD for 24 hours. The CCK-8 assay was used to determine the SSD concentration that preserves hUC-MSC viability. Flow cytometry (FCM) assessed SSD-induced apoptosis in hUC-MSCs and determined drug loading and loading efficiency. Nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM) characterized the morphology and size of hUC-MSCs-EVs and hUC-MSCs-SSD-EVs. C57BL/6J mice were divided into five groups with six mice per group: control group, periodontitis model group (PD), PD+SSD group (2 mg/kg), PD+hUC-MSCs-EVs group (10 μg/μL) and PD+hUC-MSCs-SSD-EVs group (10 μg/μL). Administration was performed 3 times a week for 4 consecutive weeks. Micro-CT and hematoxylin-eosin (HE) staining evaluated alveolar bone resorption in periodontal tissues of a mouse model of periodontitis. RT-qPCR measured inflammatory cytokine expression in periodontal tissues of a mouse model of periodontitis. Immunofluorescence analyzed macrophage M1/M2 polarization and runt-related transcription factor 2 (RUNX2) protein expression in periodontal tissues of a mouse model of periodontitis. Results The CCK-8 assay showed that 10 μmol/L SSD had little effect on hUC-MSCs viability (P>0.05). FCM confirmed the successful loading of SSD into EVs with a loading efficiency of 11.40%. TEM and NTA revealed that hUC-MSCs-SSD-EVs presented round or oval membranous structures with diameters ranging from 200 to 300 nm. Micro CT and HE staining showed that, compared with the PD group, the distance from cementoenamel junction to alveolar bone crest (CEJ-ABC) was markedly shortened (P<0.01).The alveolar bone of periodontitis‑model bone volume fraction (BV/TV) and trabecular number (Tb.N) were significantly elevated in the PD+hUC-MSCs-SSD-EVs group (P<0.01). RT-qPCR and IF results showed that hUC-MSCs-SSD-EVs in periodontal tissues markedly downregulated the expression of pro-inflammatory cytokines including interleukin-1β, interleukin-6, tumor necrosis factor-α, interleukin-12 and interleukin-22 (P<0.01), upregulated the expression of the anti-inflammatory factor interleukin-10 (P<0.01), promoted the polarization of macrophages from the M1 phenotype to the M2 phenotype, and elevated the protein expression level of RUNX2 (P<0.01). Conclusion hUC-MSC-SSD-EVs effectively alleviated inflammatory responses in a mouse model of maxillary periodontitis and reduced alveolar bone loss, providing a new idea for the treatment of periodontitis.
Objective The present study aimed to evaluate the clinical efficacy of hydraulic sinus floor elevation for the treatment of insufficient bone height in the posterior maxilla through a systematic review and Meta-analysis, so as to provide evidence for clinical practice. Methods Databases including PubMed, Embase, Cochrane Library, and Clinical Trials.gov were searched up to May 2025. Randomized controlled trials, non-randomized controlled trials, cohort studies, cross-sectional studies, and case-control studies that involved patients receiving hydraulic sinus floor elevation with simultaneous or delayed implant placement were included. Exclusion criteria comprised in vitro studies, animal experiments, narrative reviews, unpublished data, commentaries or expert opinions, studies with unclear sample sizes, and publications without full-text access or unavailable outcome data. Three investigators independently performed literature screening and quality assessment. A single-arm Meta-analysis was conducted using Stata 18.0 for studies meeting the inclusion criteria. The outcome measures were the incidence of sinus membrane perforation, implant survival rate, and endo-sinus bone gain. The Cochrane Risk of Bias 2 (RoB2) tool and the Joanna Briggs Institute (JBI) critical appraisal checklist were used to assess the methodological quality of randomized controlled trials and non-randomized controlled trials, respectively. The overall certainty of evidence was assessed using the GRADE(Grading of Recommendations Assessment, Development and Evaluation)system. Results Nineteen studies with 982 patients, 1 151 elevated sites, and 1 263 implants were finally included. The Meta-analysis showed that the intraoperative sinus membrane perforation rate of hydraulic sinus floor elevation was 2.0% [ES = 0.02, 95% CI (0.00, 0.04)] (18 studies, 1 061 sites); the implant survival rate was 99.0% [ES = 0.99, 95% CI (0.97, 1.00)] (17 studies, 1 253 implants); and the mean vertical bone gain was 7.80 mm. For this outcome, heterogeneity among studies was extremely high (I2 = 98.6%), thus only descriptive analysis was performed. Egger's test revealed no significant publication bias for the three outcomes. GRADE grading indicated very low certainty of evidence for mucosal perforation, implant survival rate, and endo sinus bone gain. Conclusion Current preliminary evidence suggests that hydraulic sinus lift may be a safe minimally invasive technique, but the evidence is very low, and more high quality, long term follow up randomized controlled clinical trials are still needed for further verification.
Objective To investigate the bactericidal efficacy and impact on oral mixed biofilm microbial structure of commonly used clinical root canal irrigants under dynamic oxygen conditions, and to provide experimental evidence for clinical root canal irrigant selection. Methods This study has been reviewed and approved by the Medical Ethics Committee, and written informed consent has been obtained from all of the participants. Two healthy oral volunteers from Beijing Stomatological Hospital, Capital Medical University were selected, and subgingival and supragingival plaque from their mandibular premolars and molars were extracted to construct an oral mixed microbial biofilm model. The plaque was cultivated on hydroxyapatite slices for 1 week (anaerobic conditions for 3 days + aerobic conditions for 4 days) to construct a young oral mixed bacterial biofilm model, and cultivated for 3 weeks (anaerobic conditions for 3 days + aerobic conditions for 18 days) to construct a mature oral mixed bacterial biofilm model. Three root canal irrigating solutions were used: sterile water (control), 2% chlorhexidine (CHX), and 1% sodium hypochlorite (NaOCl). The bacterial biofilms were treated for 1 week and 3 weeks, respectively, and the overall bactericidal rate was assessed using live/dead bacterial staining and laser confocal microscopy. Concurrently, high-throughput 16S rRNA sequencing was performed to analyze the microbial community structure and to evaluate the antibacterial effects of irrigation solution, on common dominant pathogens. Results The proportion of dead bacteria in the biofilm treated with three types of root canal irrigation drugs at 1 week and 3 weeks, from high to low, were as follows: 1% NaOCl >2% CHX >control group (P < 0.001). The bactericidal rate of 1% NaOCl on mature biofilms at 3 weeks was significantly lower than that of light biofilms at 1 year (P < 0.001). High-throughput sequencing revealed minimal effects of 2% CHX and 1% NaOCl on biofilm community structure but demonstrated poor bactericidal activity against dominant root canal pathogens, such as Streptococcus and Fusobacterium. Conclusion Under the initial anaerobic and subsequent aerobic culture conditions, 1% NaOCl exhibits potent bactericidal effects on young bacterial biofilms, but demonstrates limited efficacy against mature biofilms and certain root canal dominant bacteria (Streptococcus and Fusobacterium).
Objective To investigate the effect of injectable tetra-polyethylene glycol (PEG) hydrogels loaded with sitagliptin (STG) (abbreviated as PEG-STG hydrogels) on skin wound healing in diabetic mice, providing an experimental basis for the subsequent development of local therapeutic materials for primary healing of oral and maxillofacial skin and soft tissue wounds in patients with diabetes. Methods PEG hydrogels were fabricated via the reaction of four-arm PEG succinimidyl glutarate (PEG-SG) and four-arm PEG amine (PEG-NH2). Subsequently, PEG hydrogels loaded with STG were prepared. The microstructure, gelation, injectability, compression properties, swelling, degradation, and in vitro drug release profiles were characterized. In vitro cellular experiments were conducted using the mouse fibroblast cell line L929 and human umbilical vein endothelial cells (HUVECs), which were divided into four groups: an NC group (normal medium control), Glu group (30 mmol/L high glucose medium), PEG group (high glucose medium with PEG hydrogel extracts), and PEG-STG group (high glucose medium with PEG-STG hydrogel extracts). Biocompatibility was evaluated via CCK-8 assays, live/dead staining, and hemolysis tests. The impact of the PEG-STG hydrogels on cellular function under hyperglycemic conditions was assessed using scratch assays, Transwell migration assays, qRT-PCR, and western blotting. Furthermore, approved by the Institutional Animal Care and Use Committee of the affiliated institution, a diabetic C57BL/6J mouse skin defect model was established and divided into three groups: an NC group (normal mice control), Glu group (diabetic model control), and PEG-STG group (treated with PEG-STG hydrogel in situ). Wound healing was evaluated through gross observation, wound healing rate analysis, and histological assessment via H&E staining. Results The PEG-STG hydrogels exhibited rapid gelation at room temperature, excellent injectability, and a uniform porous structure. Compared with the PEG hydrogels, the PEG-STG hydrogels showed a significantly increased maximum compressive strength, swelling ratio, and degradation rate (P < 0.05). In vitro release profiles indicated an initial burst release of STG followed by a sustained release phase. Biocompatibility assessments confirmed that the PEG-STG hydrogels possessed good cytocompatibility and hemocompatibility. In vitro cellular experiments demonstrated that high glucose significantly inhibited the migration of the HUVECs and L929 cells, which was not ameliorated by the PEG group but was notably improved by the PEG-STG group. Moreover, the PEG-STG hydrogels upregulated the mRNA expression levels of platelet-endothelial cell adhesion molecule-1 (PECAM-1/CD31), vascular endothelial growth factor (VEGF), and von Willebrand factor in HUVECs, along with increased protein expression of VEGF and CD31. In vivo results revealed that at 14 days post-operation, the PEG-STG group exhibited significantly enhanced wound closure compared with the Glu and NC groups. H&E staining showed improved re-epithelialization, increased granulation tissue formation, and better tissue structure restoration in the PEG-STG group. Conclusion PEG-STG hydrogels possess favorable injectability and biocompatibility. They can improve endothelial cell and fibroblast function under hyperglycemic conditions and promote diabetic skin wound healing, providing a experimental basis for developing localized therapeutic materials for oral and maxillofacial wounds in patients with diabetes.
Bacterial extracellular vesicles (BEVs) are nanoscale, lipid bilayer-enclosed vesicles that are actively or passively released by bacteria. They carry diverse bioactive cargos, including proteins, nucleic acids, and lipids, and mediate information exchange between microbial communities and hosts. Increasing evidence indicates that BEVs play important roles in the initiation and progression of dental caries and periodontitis. In dental caries, BEVs derived from cariogenic bacteria such as Streptococcus mutans can promote biofilm formation and maturation, enhance the acidic microenvironment, and exacerbate demineralization of dental hard tissues. In periodontitis, BEVs released by key periodontal pathogens, including Porphyromonas gingivalis and Fusobacterium nucleatum, may disrupt the mucosal barrier, trigger inflammatory responses, and activate bone resorption-related pathways, thereby promoting periodontal tissue destruction. Owing to their detectability, BEVs in oral samples such as saliva, dental plaque, and gingival crevicular fluid show promise as diagnostic biomarkers and also provide new therapeutic opportunities for targeted interventions. In addition, emerging studies suggest that oral BEVs may contribute to distal inflammatory amplification through an “oral-systemic axis”; therefore, while focusing on the local pathogenic mechanisms of BEVs in dental caries and periodontitis, this review also briefly outlines their potential systemic implications as an extension. Overall, BEVs may offer novel mechanistic insights and translational directions to support precise prevention and management of dental caries and periodontitis.
Objective To investigate the effects of curcumin on the biological behavior of oral squamous cell carcinoma (OSCC) cells and its potential molecular mechanisms, as well as to provide experimental evidence for the application of curcumin in the prevention and treatment of OSCC. Methods All animal experiments in this study were approved by the Institutional Animal Welfare and Ethics Committee and strictly adhered to relevant animal ethics guidelines. Potential intersecting targets of curcumin and OSCC were screened using TCMSP, SwissTargetPrediction, DrugBank, and GeneCards databases, followed by construction of a protein-protein interaction network and gene ontology(GO) /Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Scratch and clone formation experiments were conducted using CAL-27 and SCC-9 cells to detect the effect of curcumin on cell migration and proliferation ability. Combining RNA sequencing analysis of differentially expressed genes, and verifying the changes in mRNA and protein expression of key cellular molecules by curcumin through real-time fluorescence quantitative PCR and Western blot, respectively. Simultaneously establish a CAL-27 xenograft BALB/c nude mouse transplant tumor model and use immunohistochemistry to detect the effect of curcumin treatment on the expression of related proteins in the transplant tumor tissue. Results A total of 178 intersecting targets were identified, mainly enriched in the PI3K/AKT signaling pathway and lipid metabolism-related pathways. Curcumin significantly inhibited migration and colony formation of CAL-27 and SCC-9 cells in vitro. Transcriptomic analysis identified 828 differentially expressed genes enriched in lipid metabolism and PI3K/AKT pathways. Real-time fluorescence quantitative PCR showed downregulation of PIK3CA, CCND1, BCL2, and FASN, while western blot demonstrated decreased expression of p-AKT and FASN. In vivo, curcumin markedly suppressed tumor growth and reduced the expression of Ki-67, BCL2, and p-AKT in tumor tissues. Conclusion Curcumin may inhibit the migration and proliferation of OSCC cells by regulating the PI3K/AKT signaling pathway and the expression of lipid metabolism-related genes.
Objective To investigate the therapeutic effect of a dual-network hydrogel-microneedle(MN)on inhibit-ing oral squamous cell carcinoma(OSCC)recurrence and promoting tissue repair,thereby providing a foundation for the clinical treatment of OSCC.Methods A Schiff base hydrogelformed between chitosan(CS)and poly(ethylene glycol)dibenzaldehyde(PEG-CHO),combined witha coordination-crosslinked hydrogel formed between sodium alginate(SA)and Cu²⁺,were jointly integrated to form the CS/PEG-CHO/SA/Cu²⁺(CPSC)dual-network hydrogel base.The hydrogel formulation was optimized based on characterization by scanning electron microscopy,Fourier transform infrared spec-troscopy,rheology,and swelling tests.Subsequently,5-fluorouracil(5-FU)and gold nanorod(GNR)were incorporated into the CPSC hydrogel to fabricate an MN loaded with 5-FU/GNR(FG).The mechanical strength and dissolution be-havior of FG MNs were characterized,and their photothermal performance was evaluated under near-infrared(NIR)irra-diation using thermal imaging.The mouse fibroblast cell line L929 cells and the human oral mucosal epithelial-derived cell line GMSM-K cells were co-cultured with FG MNs for 2 and 4 days,respectively,and cell viability was assessed by the Cell Counting Kit-8(CCK-8)assay and dead/live staining.Separately,the human tongue OSCC cell line Cal-27 cells were divided into four groups:a control group(cultured in complete medium),5-FU MN group(co-cultured with 5-FU-loaded MNs),GNR MN+NIR group(co-cultured with GNR-loaded MNs followed by NIR irradiation at 0.4 W/cm2 for 5 min),and FG MN+NIR group(co-cultured with FG MNs followed by identical NIR irradiation).After 24 and 48 h of co-culture,Cal-27 cell viability was assessed using both CCK-8 assay and dead/live staining.All animal experi-ments were approved by the Institutional Animal Ethics Committee.A subcutaneous Cal-27-derived OSCC postopera-tive recurrence model was established in BALB/c nude mice.The mice were divided into four groups:a control group,5-FU MN group,GNR MN+NIR group,and FG MN+NIR group.Mice in the control group received no intervention,while the other groups were treated with the corresponding MN patches.Additionally,the GNR MN+NIR and FG MN+NIR groups received NIR irradiation(0.4 W/cm2,5 min).Tumors were excised and their volumes measured on day 7,and tumor recurrence and wound healing were assessed on day 14.Results A dual-network hydrogel-MN was success-fully constructed,demonstrating favorable mechanical and dissolution properties.Upon NIR irradiation for 5 min,the temperature rapidly increased to 48.4℃,reaching the threshold for effective tumor ablation.CCK-8 and dead/live stain-ing results showed that FG MNs exhibited no cytotoxicity toward L929 and GMSM-K cells,indicating good cytocompat-ibility.However,Cal-27 cell viability in the chemotherapy-photothermal combination group was lower than that in the other three groups,with a statistical difference(P<0.0001).In the nude mouse model,subcutaneous Cal-27 tumors were resected 7 days post-implantation.No statistical difference in tumor volume was observed among groups at this timepoint,confirming successful model establishment.By postoperative day 14,the control group displayed complete tumor recurrence with unhealed wounds,while the 5-FU and GNR MN+NIR groups showed mild recurrence and par-tial wound healing.The FG MN+NIR group demonstrated superior efficacy in both inhibiting tumor recurrence and promoting tissue repair compared with all other groups,with a statistical difference(P<0.0001).Conclusion The dual-network hydrogel-MN system effectively suppresses postoperative recurrence of Cal-27-derived subcutaneous OSCC and promotes tissue repair through chemo-photothermal combined therapy.
Patients with periodontitis face significantly increased risks of implant failure and peri-implantitis. These adverse outcomes are mainly associated with the enrichment of periodontal pathogens and microbial dysbiosis, host immune imbalance, smoking, and poor adherence to supportive periodontal therapy. In addition, complex hard- and soft-tissue defects and occlusal trauma caused by periodontitis further increase the complexity and long-term uncertainty of implant therapy. Therefore, implant treatment in patients with periodontitis should adopt a systematic management strategy centered on “inflammation control, functional reconstruction, and long-term maintenance.” On the premise of periodontal inflammation control and stable maintenance, clinicians should comprehensively evaluate the remaining dentition, hard-tissue and soft-tissue defects, dental implant surgical plan, prosthetic modality, and occlusal load. When necessary, hard-tissue and soft-tissue augmentation procedures should be performed to reconstruct a stable tissue foundation. Digital technologies should also be integrated to coordinate the three-dimensional implant position, tissue support, and biomechanical load distribution, thereby achieving stable functional and esthetic rehabilitation. Further, risk stratification, plaque control, host inflammatory modulation, supportive periodontal therapy, and behavioral interventions should be reinforced to improve the long-term stability and predictability of implant rehabilitation. In the future, the integration of multi-omics technologies, artificial intelligence-based risk prediction, digital-intelligent implant workflows, and novel regenerative materials may further promote individualized precision therapy.
Objective To investigate the effects of grain size and immersion dyeing time on the dye penetration depth and color parameters of zirconia, and analyze the dyeing behavior in relation to the material's pore characteristics to provide experimental evidence for developing personalized immersion staining protocols for clinical applications targeting zirconia with different microstructures. Methods A total of 135 pre-sintered zirconia specimens with three different grain sizes were fabricated using computer aided design/manufacturing technology and divided into three groups (S1, S2, S3; n=45). Randomly select 6 specimens from each group, among which 3 zirconia pre sintered specimens are soaked in 10 mL A2 staining solution for 60 s, dried and sintered, and the other 3 are not treated. Observe the microstructure of the outer surface and bonding surface of the specimen under SEM, and use Image J software to count and measure the grain size. From each group, three randomly selected specimens were subjected to mercury intrusion porosimetry to analyze porosity and pore size distribution. For the remaining specimens, the bottom surface (10 × 10 mm) was designated as the staining surface and immersed in 10 mL of A2 staining liquid. The remaining specimens were stained at six time gradients (10, 20, 30, 60, 90, 120 s). After staining, half of the specimens were sectioned perpendicular to the stained surface and fully sintered to measure the staining penetration depth. The other half were directly fully sintered. A spectrophotometer was used to measure the color parameters (L*, a*, b*) of the stained surface, and the color difference (ΔE00) relative to a standard A2 shade tab was calculated. Results The average grain sizes (G) for the three groups were GS1=(221.64±62.16) nm, GS2=(197.80±46.72) nm, and GS3=(150.21±42.11) nm; the average porosities (P) were PS1=37.82%, PS2=46.02%, and PS3=47.36%. Both grain size and staining time significantly affected the staining outcome of zirconia (P<0.001), with a significant interaction effect (P<0.001). Staining penetration depth increased with prolonged staining time and decreased grain size (P<0.001). All fully sintered specimens exhibited a perceptible color difference (ΔE00>0.8) compared with the standard A2 shade tab (VITA, USA). Specifically, specimens from group S1 stained for 20 s, group S2 stained for 60 s, and group S3 stained for 10 s exhibited color differences below the clinically acceptable threshold (ΔE00<1.8), meeting clinical thickness requirements. Specimens stained for other time intervals exceeded the clinically acceptable color difference threshold (ΔE00>1.8). Conclusion The porosity of pre-sintered zirconia with different grain sizes varied. Higher porosity correlated with deeper staining penetration. The staining time required to achieve the standard A2 shade differed among zirconia materials with different grain sizes. In clinical applications, the immersion dyeing protocol for zirconia should be optimized based on the grain size and pore characteristics of zirconia with different grain sizes, so as to avoid color deviations caused by improper dyeing time.
Skeletal Class Ⅱ malocclusion is a common dentofacial deformity in adolescents,primarily characterized by mandibular retrognathism.Functional appliance therapy during the pubertal growth spurt to guide mandibular ad-vancement is considered the gold standard.However,traditional functional appliances are often associated with limita-tions such as bulkiness,poor esthetics,and soft tissue irritation,which can compromise patient compliance.With ad-vancements in digital orthodontics,clear aligner technology integrated with mandibular advancement(clear aligner man-dibular advancement,CAMA)has emerged as a novel strategy for treating adolescent skeletal Class Ⅱ malocclusion,of-fering advantages in esthetics and comfort while significantly improving patient compliance.CAMA exhibits multidimen-sional clinical advantages in adolescent malocclusion correction:① Its mechanical mechanism based on material visco-elasticity optimizes temporomandibular joint stress distribution and induces physiological condylar remodeling,micro-scopically manifested as increased trabecular fractal dimensions;② While ensuring mandibular growth,it effectively controls molar eruption through the"bite block effect,"providing an optimal solution for vertical control in high-angle cases,and the enhanced precision wing design significantly improves torque control of lower incisors;③ It improves oropharyngeal airway morphology and respiratory function,benefiting patients'overall health.Although CAMA holds significant value in treating skeletal Class Ⅱ malocclusion,current research remains insufficient regarding the specific proportions of skeletal versus dental effects,long-term stability of treatment outcomes,and therapeutic boundaries for severe skeletal discrepancies,with most studies being retrospective or short-term.Future research should prioritize pro-spective multicenter randomized controlled trials,establish personalized diagnostic and treatment systems integrating ar-tificial intelligence-assisted design and biomechanical simulation,and comprehensively analyze multiple factors includ-ing temporomandibular joint adaptability to further enhance the clinical value of CAMA.
Temporomandibular joint (TMJ) is the only synovial joint in the oral and maxillofacial region, with its disc being a critical fibrocartilaginous structure that distributes stress and maintains the stability of joint movement. Various factors can lead to TMJ disc destruction, resulting in TMJ dysfunction and facial deformities. In recent years, research on TMJ disc destruction has become a frontier in the field of oral and maxillofacial surgery. Previous research and literature reviews have mainly focused on diagnosis and treatment, with a lack of reviews on the progress of basic research related to disc destruction. This review summarizes current progress in the etiology, pathological features, molecular mechanisms, and tissue-engineered repair materials of TMJ disc destruction, providing reference for basic research and clinical prevention and treatment. Studies have shown that the causes of TMJ disc destruction include mechanical damage (e.g. anterior disc displacement, malocclusion, trauma), chronic inflammation (e.g. TMJ osteoarthritis, rheumatoid arthritis), and susceptibility factors such as age and sex, as well as psychosocial factors. Its main manifestations are alterations in the ultrastructure and mechanical properties of collagen fibers. Its molecular mechanisms include abnormal angiogenesis, imbalanced fibrocartilage cell homeostasis under mechanical or inflammatory stimulation, and abnormal stem cell differentiation. The present study focuses on the development and optimization of tissue engineered biomaterials through cell sources, scaffold materials, and growth factors. Future studies should focus on the molecular mechanisms of TMJ disc destruction, regulation of disc development during embryonic and postnatal stages, development and translation of novel biomaterials, as well as the application of artificial intelligence in material design, molecular target screening, and clinical decision-making.
Oral potentially malignant disorders (OPMDs) are a group of oral mucosal diseases with different morphological characteristics that have an increased risk of progressing to oral squamous cell carcinoma (OSCC). Epidemiological studies indicate that approximately 4.67% of the global population may have an OPMD, and meta-analysis results show that the risk of progression to OSCC in patients with OPMD is 2.5 times that of the general population. The progression of an OPMD to OSCC is a complex process driven by risk factors including smoking, alcohol consumption, betel quid chewing, and oral microbiota. It is characterized by intricate interactions among genetic alterations, epigenetic modifications, and dysregulation of the tumor microenvironment. At the molecular level, the intrinsic basis of epithelial carcinogenesis is established by genomic loss of heterozygosity and cascading dysregulation of critical signaling pathways, while crucial external support for malignant transformation is provided by the immunosuppressive microenvironment, including M2 macrophage polarization, immune evasion mediated by programmed death-ligand 1, and the pro-tumorigenic effects of oral microbiota. Although a variety of therapeutic modalities (e.g., pharmacotherapy, surgical treatment, and photodynamic therapy) have been employed for the prevention of OPMD malignant transformation, no universally accepted treatment has been proven to completely eradicate the risk of cancer development at present. In recent years, artificial intelligence technologies have demonstrated promising performance in predicting the malignant transformation risk of OPMD by integrating multi-dimensional clinical, pathological, and molecular data, thereby providing new decision-support tools for advancing individualized risk stratification and precise follow-up management. This review summarizes recent advances in the prevention of OPMD malignant transformation, with the aim of offering a reference for the clinical management of OPMDs.
Objective To investigate changes in lactate and histone lactylation during senescence of mouse bone marrow mesenchymal stem cells (BMSCs), to clarify the effects of regulating lactate metabolism on the osteogenic differentiation of senescent BMSCs, and to provide theoretical evidence and an experimental basis for metabolic regulatory interventions in aging-related osteoporosis and impaired bone repair. Methods Approval was obtained from the Institutional Laboratory Animal Ethics Committee. BMSCs were isolated using the whole bone marrow adherence method and surface markers (CD29, CD90, CD11b and CD45) and identified by flow cytometry. A cellular model of BMSCs senescence was established using different concentrations of etoposide (0, 5, 10, 15, and 20 μmol/L). The gene and protein expression levels of senescence-related markers, namely, p53, p21, and p16, were detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot analysis, and the optimal induction concentration was determined using CCK-8 and SA-β-gal assays. BMSCs were divided into a control group and an etoposide-induced senescence group to examine lactate production and the expression of histone lactylation-related enzymes, including Ldha, Ep300, and Sirt2. Western blot analysis was used to analyze pan-lysine lactylation(Pan-Kla) and histone H3 lysine 18 lactylation (H3K18la). During the lactate production inhibition experiments, BMSCs were divided into three groups: control, senescence group (treated with 10 μmol/L etoposide), and senescence+ GNE-140 group (treated with 10 μmol/L etoposide and 1 μmol/L GNE-140). qRT-PCR, Western blot, and SA-β-gal staining were performed to assess the effects of lactate production inhibition on cellular senescence phenotypes. During osteogenic differentiation, BMSCs were assigned to a control group, senescence group (treated with 10 μmol/L etoposide), senescence+ 5 mmol/L sodium lactate group, and senescence+ 10 mmol/L sodium lactate group. The levels of Pan-Kla and H3K18la were detected by Western blot. The mRNA expressions of runt-related transcription factor 2 (Runx2), transcription factor Sp7 (Sp7) and alkaline phosphatase (Alpl) were detected by qRT-PCR. The protein expressions of collagen type I (COL1), RUNX2, osterix (OSX) and osteocalcin (OCN) were detected by Western blot, and mineralized nodule formation was observed by Alizarin Red S staining. Results Flow cytometry analysis indicated that the isolated BMSCs highly expressed CD29 (97.3%) and CD90 (95.7%). Etoposide induced BMSC senescence by activating the p53-p21 signaling pathway, with an optimal concentration of 10 μmol/L. Compared with the control group, BMSCs exhibited decreased lactate production, reduced mRNA expression of Ldha and Ep300 (P<0.001), upregulated Sirt2 expression (P<0.01), and diminished levels of Pan-Kla and H3K18la modification (P<0.001). Further inhibition of lactate production with GNE 140 further increased the expression levels of p53 and p21 and the percentage of SA β gal positive cells (P<0.01). In osteogenic differentiation experiments, the expression levels of Runx2, Sp7, Alpl mRNA and COL1, RUNX2, OSX, OCN proteins, as well as the mineralized nodule formation ability of senescent BMSCs, were decreased (P<0.05); exogenous supplementation with 5 mmol/L and 10 mmol/L sodium lactate can increase the levels of panolactic lactation and histone lactation, and improved the osteogenic differentiation capacity and mineralized nodule formation of senescent BMSCs. Conclusion BMSC senescence is associated with reduced lactate production and decreased histone lactylation levels. Exogenous supplementation with sodium lactate partially rescues osteogenic differentiation impairment in senescent BMSCs.
Objective To investigate the factors influencing follow-up visit behavior among patients with chronic periodontitis after supragingival scaling, and to provide evidence for early identification of high-risk dropouts and improvement of treatment continuity. Methods This study was approved by the Institutional Medical Ethics Committee, and written informed consent was obtained from all participants. A retrospective analysis was conducted on 572 patients with chronic periodontitis who received supragingival scaling at the Outpatient Department of The Affiliated Stomatological Hospital of Nanjing University School of Medicine from July 2022 to July 2023 and required subsequent periodontal sequential therapy. Data regarding sex, age, monthly income, education level, oral health literacy, reason for visit, and satisfaction with care were collected. Patients were divided into a follow-up group and a dropout group based on whether they adhered to the scheduled appointments within 12 months. Chi-square tests and independent samples t-tests were used for univariate comparisons between the groups. Variables with P<0.05 in the univariate analysis (gender, education level, monthly income, reason for visit, oral health literacy, and satisfaction with care), along with age (as a covariate), were included in a multivariate logistic regression model to analyze the factors influencing follow-up behavior. Results Among the 572 patients, 239 attended follow-up visits, while 333 dropped out, resulting in a dropout rate of 58.22%. Univariate analysis revealed statistically significant differences between the two groups in terms of gender, education level, monthly income, reason for visit, oral health literacy, and satisfaction with care (P<0.05). Multivariate logistic regression analysis showed that patients referred for treatment had significantly lower compliance (OR=0.241, 95% CI: 0.154-0.377, P<0.001). Conversely, higher oral health literacy scores (OR=1.159, 95% CI: 1.056-1.272, P=0.002) and higher satisfaction with care (OR=4.090, 95% CI: 1.732-9.656, P=0.001) were associated with better follow-up adherence. Conclusion Follow-up behavior in patients with chronic periodontitis after supragingival scaling is primarily influenced by the reason for visit, oral health literacy, and satisfaction with care. These factors can serve as intervention targets to reduce dropout rates in clinical practice.
Objective To investigate the effect of different pre-stretching on the force degradation of elastomeric chains methods and provide experimental evidence for its application in clinical orthodontic treatment. Methods One control group (no pre-stretched treatment) and 15 experimental groups (pre-stretched to 25%, 50%, and 100% of the original length in 1-5 cycles) were set up by taking five loop lengths of short elastomeric chain and long elastomeric chain samples, respectively. The elastomeric chains from both the control and experimental groups were mounted on the testing fixture at identical initial lengths. To simulate tooth movement, the fixation device was adjusted to reduce the distance by 0.35 mm weekly. The remaining force of each group was measured at different time points over a 4-week period. Further, the experiment was conducted in a simulated salivary environment with additional thermal cycling. Results Pre-stretching length and cycles showed a significant interaction effect on the remaining force of elastomeric chains (P<0.001). For short elastomeric chains, the groups pre-stretched to 25% (P=0.001) and 50% (P=0.005) of the original length for 3 cycles showed significantly higher remaining force values than the control group at 24 h. At 7, 14, 21, and 28 d, the groups pre-stretched to 25%, 50%, and 100% of the original length for 3 cycles consistently maintained higher remaining force values than the control group (P<0.001). Within the groups of 3 pre-stretching cycles, no significant differences in remaining force were observed among the 50% group and the 25% (P=0.617) or 100% (P=0.229) groups at 7 d. However, at 14 d, the remaining force of the 50% group was significantly higher than that of both the 25% (P=0.003) and 100% (P=0.027) groups. At 21 d, the 50% group maintained a significantly higher remaining force compared to the 100% group (P=0.020), but the difference compared to the 25% group did not reach statistical significance (P=0.052). By 28 d, the remaining force of the 50% group remained significantly higher than that of both the 25% (P=0.003) and 100% (P=0.003) groups. For long elastomeric chains, the 50% pre-stretch (3 cycles) group showed significantly higher remaining force values than the control group at 8 h (P=0.005) and 24 h (P<0.001). Throughout the experimental period at 7, 14, 21, and 28 d, the remaining force values of the 25% (7, 14 d: P<0.001; 21 d: P=0.003; 28 d: P=0.008), 50% (P<0.001), and 100% (P<0.001) original length pre-stretching for 3 cycles groups were consistently higher than those of the control group. Within the groups of 3 pre-stretching cycles, the remaining force of the 50% original length pre-stretching for 3 cycles group was significantly higher than that of the 25% original length pre-stretching for 3 cycles group at all of the time points from 7 to 28 d (P<0.001). Although no statistically significant differences were observed between the 50% and 100% groups at 14 d (P=0.068), the 50% group exhibited significantly higher remaining force than the 100% group at 7 d (P<0.001), 21 days (P=0.005), and 28 days (P<0.001). Conclusion Appropriate pre-stretching methods can effectively delay the force degradation of the elastomeric chain. Pre-stretching to 50% original length for three cycles can maximize the delay of the force degradation of the elastomeric chain.
This paper systematically elaborates on the key points of diagnosis and differential diagnosis of salivary gland tumors characterized by a substantial amount of extracellular mucus as a main or prominent feature,and clarifies the core differential features.The term"mucus-rich"specifically denotes that mucus is a major component of the tumor,rather than a focal or minor one.This phenomenon is associated with distinct histogenetic mechanisms:it may result from specific genetic mutations(e.g.,AKT1 E17K in mucinous adenocarcinoma)that drive ductal epithelial differentia-tion into mucus-secreting cells,or from myoepithelial cells secreting glycosaminoglycans that form a myxoid stroma.Salivary gland tumors with abundant extracellular mucus include mucinous cystadenoma,sialadenoma papilliferum-like intraductal papillary tumors,mucinous myoepithelioma,pleomorphic adenoma with mucin-rich stroma,mucinous adeno-carcinoma,low-grade mucoepidermoid carcinoma,mucin-rich salivary duct carcinoma and intestinal-type adenocarci-noma.The diagnosis of these tumors is complicated by the dual nature of extracellular mucus:while it is a defining fea-ture of some entities,it can also obscure key diagnostic architectural features in others,leading to histological overlap and inconspicuous diagnostic areas.Given the frequent histological morphological overlap among these tumors,immuno-histochemical findings and molecular characteristics have emerged as crucial differential diagnostic criteria.Core differ-ential diagnostic points include the following:histologically,there must be meticulous identification of typical structures obscured by mucin(such as squamoid cells in mucoepidermoid carcinoma and apocrine features in salivary duct carci-noma);in immunohistochemical staining,CK20 is useful for distinguishing intestinal-type adenocarcinoma(positive)from mucinous adenocarcinoma(negative),while androgen receptor aids in differentiating salivary duct carcinoma(posi-tive)from mucoepidermoid carcinoma(negative);and molecular testing plays a critical role in definitive diagnosis(e.g.,the AKT1 E17K mutation for mucinous adenocarcinoma,MAML2 rearrangement for mucoepidermoid carcinoma,and MEF2C::SS18 fusion for microsecretory adenocarcinoma).This paper systematically summarizes the core pathological features and differential diagnostic points of mucin-rich salivary gland tumors,aiming to provide a practical reference for clinical pathological diagnosis.
Objective To compare the effects of immediate versus delayed post-space preparation on the bond strength of fiber posts and the fracture resistance of roots after root canal obturation using iRoot SP and the single-cone technique, and to provide an experimental basis for the selection of the timing of clinical post-space preparation. Methods This study was approved by the Medical Ethics Committee of the institution, and written informed consent was obtained from all participants. Seventy-two extracted human single-rooted premolars were randomly divided into two groups (n = 36 each): the immediate post-space preparation group (post-space preparation performed immediately after root canal obturation) and the delayed post-space preparation group (post-space preparation performed 1 week after root canal obturation). Cleanliness of the root canal walls was assessed with a dental microscope after preparation in both groups; the ultrastructural characteristics of the dentinal surface were examined via scanning electron microscopy; the fracture resistance of roots was measured with root fracture resistance tests; the bond strength of the fiber posts was measured with the thin-slice push-out test; and the bond failure modes were observed and analyzed under a stereomicroscope. Results Under dental microscopy, the dentin surface of the immediate post-space preparation group appeared cleaner than that of the delayed post-space preparation group. Scanning electron microscopy revealed that most dentinal tubules remained open in the immediate post-space preparation group, while the tubules in the delayed post-space preparation group showed incomplete patency. The fracture resistance of the immediate post-space preparation group was (2 872 ± 241.5) N and that of the delayed post-space preparation group was (2 934 ± 353.1) N, with no statistically significant difference (t = -0.328, P = 0.751). The push-out bond strength of the immediate post-space preparation group (10.310 ± 2.907) MPa was significantly higher than that of the delayed post-space preparation group (7.917 ± 2.429) MPa, with a statistically significant difference (t = 4.457, P < 0.001). Analysis of failure modes showed that adhesive-to-dental interface failure was the predominant mode in both groups. Conclusion Following root canal obturation with iRoot SP using the single-cone technique, immediate post-space preparation yields superior fiber post bond strength compared to delayed post-space preparation, without compromising root fracture resistance.
Objective To analyze the clinical characteristics and management strategies of metronidazole-associated Stevens-Johnson syndrome (SJS), and to provide a clinical basis for medication safety during the oral perioperative period. Methods The study adhered to the tenets of the Declaration of Helsinki and was approved by the Ethics Committee of Stomatological Hospital of Xi'an Jiaotong University. A retrospective analysis was conducted on a case of SJS following mandibular impacted tooth extraction, for which the patient had taken metronidazole. Additionally, a literature review was performed by searching databases including China National Knowledge Infrastructure, Wanfang, PubMed, and Web of Science to identify reported cases of metronidazole-associated SJS. Demographic features, medication regimens, latency periods, clinical signs, interventions, and prognosis were analyzed. Results The patient presented with lip swelling, extensive erosion and ulceration of the oral mucosa, and severe odynophagia. Scattered erythematous macules and bullae were observed on the trunk and extremities, with a positive Nikolsky sign. Additionally, there was erosion of the perineal skin and glans penis mucosa, along with skin desquamation of the scrotum. The patient with SJS was managed in the hospital by discontinuing metronidazole and administering sequential treatments, including glucocorticoids, immunomodulators, intravenous immunoglobulin, and plasma exchange. The condition gradually improved; after a 14-month follow-up, only mild dry eye remained, with no significant scarring of the skin or mucosa. However, delayed recognition of early warning signs resulted in delayed drug withdrawal and intervention. The literature review identified 6 additional cases (3 males, 3 females) with a median age of 45.5 years (range 31-61). Indications for metronidazole included postoperative sepsis prophylaxis after duodenal ulcer perforation repair, digestive system infections, mucosal diseases, pelvic inflammatory disease, septic cellulitis with pneumonia, and gingivitis. Administration routes comprised oral (n = 2), intravenous (n = 3), and topical (n = 1). The latency period from drug administration to onset ranged from 0.25 to 7 days (median 4 days). All of the cases presented with oral mucosal erosion, and a positive Nikolsky’s sign was noted for five patients. Discontinuation of the causative drug was the cornerstone of treatment, supplemented by immunomodulatory therapy, symptomatic support, and multidisciplinary collaboration. Prognoses varied significantly: among the four patients treated with “drug withdrawal + glucocorticoids + supportive care,” three recovered fully and one improved; among the two patients receiving “drug withdrawal + simple supportive care,” one recovered and one died. Conclusion Although metronidazole-associated SJS is rare, it progresses rapidly and frequently involves oral mucosal damage, typically occurring within one week of administering the medication. Early drug withdrawal and prompt initiation of glucocorticoid therapy can improve prognosis. During the oral perioperative period, strict adherence to metronidazole indications, enhanced monitoring for early warning symptoms, and the establishment of a multidisciplinary collaborative diagnosis and treatment model are essential to minimize the risk of severe adverse drug reactions.