Periodontitis is a common oral disease characterized by progressive alveolar bone resorption and inflammation of the periodontal tissues. Dimethyl fumarate (DMF) has been used in the treatment of various immune-inflammatory diseases due to its excellent anti-inflammatory and antioxidant functions. Here, we investigated for the first time the therapeutic effect of DMF on periodontitis. In vivo studies showed that DMF significantly inhibited periodontal destruction, enhanced mitophagy, and decreased the M1/M2 macrophage ratio. In vitro studies showed that DMF inhibited macrophage polarization toward M1 macrophages and promoted polarization toward M2 macrophages, with improved mitochondrial function, inhibited oxidative stress, and increased mitophagy in RAW 264.7 cells. Furthermore, DMF increased intracellular mitochondrial Tu translation elongation factor (TUFM) levels to maintain mitochondrial homeostasis, promoted mitophagy, and modulated macrophage polarization, whereas TUFM knockdown decreased the protective effect of DMF. Finally, mechanistic studies showed that DMF increased intracellular TUFM levels by protecting TUFM from degradation via the ubiquitin-proteasomal degradation pathway. Our results demonstrate for the first time that DMF protects mitochondrial function and inhibits oxidative stress through TUFM-mediated mitophagy in macrophages, resulting in a shift in the balance of macrophage polarization, thereby attenuating periodontitis. Importantly, this study provides new insights into the prevention of periodontitis.
Dimethyl Fumarate/pharmacology* ; Mitophagy/drug effects* ; Animals ; Mice ; Macrophages/metabolism* ; Periodontitis/prevention & control* ; RAW 264.7 Cells ; Oxidative Stress/drug effects* ; Peptide Elongation Factor Tu/metabolism* ; Mice, Inbred C57BL ; Male ; Mitochondria/drug effects*

Cemental tear is a rare and indetectable condition unless obvious clinical signs present with the involvement of surrounding periodontal and periapical tissues. Due to its clinical manifestations similar to common dental issues, such as vertical root fracture, primary endodontic diseases, and periodontal diseases, as well as the low awareness of cemental tear for clinicians, misdiagnosis often occurs. The critical principle for cemental tear treatment is to remove torn fragments, and overlooking fragments leads to futile therapy, which could deteriorate the conditions of the affected teeth. Therefore, accurate diagnosis and subsequent appropriate interventions are vital for managing cemental tear. Novel diagnostic tools, including cone-beam computed tomography (CBCT), microscopes, and enamel matrix derivatives, have improved early detection and management, enhancing tooth retention. The implementation of standardized diagnostic criteria and treatment protocols, combined with improved clinical awareness among dental professionals, serves to mitigate risks of diagnostic errors and suboptimal therapeutic interventions. This expert consensus reviewed the epidemiology, pathogenesis, potential predisposing factors, clinical manifestations, diagnosis, differential diagnosis, treatment, and prognosis of cemental tear, aiming to provide a clinical guideline and facilitate clinicians to have a better understanding of cemental tear.
Humans ; Dental Cementum/injuries* ; Consensus ; Diagnosis, Differential ; Cone-Beam Computed Tomography ; Tooth Fractures/therapy*

Objective:To clarify the potential correlation between biological changes of meninges in periodontitis mice and cognitive impairment by analyzing the biological changes of meninges in periodontitis mice using single-cell RNA sequencing.Methods:Thirty C57BL/6 mice were divided into two groups by using random number table method (15 mice in each group). Mice in the control group were locally administered 2% carboxyl methyl cellulose (CMC) without Porphyromonas gingivalis (Pg) on both buccal sides. A mixture of Pg W83 and 2% CMC was applied on both buccal sides in the experimental group mice three times a week, lasting for 16 weeks in total. The absorption of alveolar bone, locomotor activity and cognitive function, the activation of microglia and astrocytes in the cortex were observed and assessed. The mRNA expression levels of Occludin in meninges and brain were detected in two groups. Single-cell RNA sequencing data of meninges were processed by uniform manifold approximation and projection (UMAP). Differential genes expressions of endothelial cells were processed by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. In addition, real-time fluorescence quantitative PCR (RT-qPCR) was used to verify the expressions of transcription activating factor 3 (Atf3) and apolpoprotein L domain-containing 1 (Apold 1). Results:Methylene blue staining found the distances of buccal and palatal cement-enamel junction-alveolar bone crest in experimental mice [(185.60±17.60), (206.90±13.37) μm] increased significantly compared with the control group [(135.33±9.57), (163.05±14.98) μm] ( t=5.02, P=0.002; t=4.37, P=0.005). Open field experiment showed the total distance and average speed of mice in the experimental group [(971.88±164.57) cm, (3.25±0.55) cm/s] were not statistically significant compared with the control group [(914.24±278.81) cm, (3.05±0.93) cm/s] ( t=0.65, P=0.525; t=0.65, P=0.520). The recognition index of the experimental group [(48.02±16.92) %] was lower than the control group [(66.27±17.90) %] ( t=2.40, P=0.027) by novel object recognition tests. Compared with the control group [(63.56±11.88) %], the alternation of experimental group [(50.99±14.17) %] was significantly decreased in Y maze tests ( t=2.33, P=0.030). Immunohistochemistry results showed microglia and astrocytes were activated in the cortex of experimental mice. Compared with the control group (1.02±0.25, 1.04±0.31), the relative mRNA expressions of Occludin decreased significantly in the meninges and brain of periodontitis mice, respectively (0.61±0.10, 0.64±0.20) ( t=3.47, P=0.010; t=2.66, P=0.024). By single-cell RNA sequencing, meninges cells were divided into 11 types, such as endothelial cells, fibroblasts, immune cells and so on. Endothelial cells were the main cell types in meninges [the control group: 26.47% (1 589/6 004), the experimental group: 26.26% (807/3 073)]. Compared with the control group [5.56% (334/6 004)], the percentage of granulocytes increased in the periodontitis mice [11.65% (358/3 073)]. Using clustering analysis to further focus on endothelial cells, GO enrichment analysis revealed differential genes were mainly related to angiogenesis, cell adhesion, apoptosis and so on. KEGG enrichment analysis revealed that differential genes were related to signaling pathways of interleukin-17, relaxin and so on. The relative mRNA expressions of Atf3 and Apold1 in meninges of periodontitis mice (0.42±0.24, 0.54±0.27) were significantly lower than the control group (1.03±0.26, 1.02±0.23) ( t=3.88, P=0.005; t=3.02, P=0.017). Conclusions:The mice chronically infected with Pg W83 occurred memory impairment, neuroinflammation and changes of barrier function. In the meninges of periodontitis mice, there were infiltration of immune cells and down-regulation expressions of Atf3 and Apold1 by single-cell RNA sequencing. Meningeal immunity and changes of barrier function may play an important role in the cognitive impairment caused by periodontitis.

Endo-periodontal lesions(EPLs)involve both the periodontium and pulp tissue and have complicated etiologies and pathogenic mechanisms,including unique anatomical and microbiological characteristics and multiple contributing factors.This etiological complexity leads to difficulties in determining patient prognosis,posing great challenges in clinical practice.Furthermore,EPL-affected teeth require multidisciplinary therapy,including periodontal therapy,endodontic therapy and others,but there is still much debate about the appropriate timing of periodontal therapy and root canal therapy.By compiling the most recent findings on the etiology,pathogenesis,clinical characteristics,diagnosis,therapy,and prognosis of EPL-affected teeth,this consensus sought to support clinicians in making the best possible treatment decisions based on both biological and clinical evidence.

Objective·To observe the effects of gingipain extract on the biological characteristics of oral squamous cell carcinoma cell HN6.Methods·The HN6 cell line was selected,cultivated,and divided into different groups based on the protein concentration of gingipain extract from Porphyromonas gingivalis:control group,3.125 μg/mL group,6.25 μg/mL group,12.5 μg/mL group,25 μg/mL group,50 μg/mL group,and 100 μg/mL group.After 24 and 48 h of cultivation,CCK-8 assay was used to detect the effects of gingipain extract on HN6 cell proliferation activity.Subsequent experiments were divided into control group,25 μg/mL group and 50 μg/mL group.Flow cytometry was used to examine the effects of gingipain extract on cell cycle.Scratch assay and Transwell assay were performed to evaluate cell migration and invasion ability.Real-time PCR(RT-PCR)and Western blotting were used to measure the expression of E-cadherin and N-cadherin proteins and genes in cells.Results·Stimulated with gingipain extract for 24 h,the HN6 cells showed significantly increased proliferation activity in the 25 μg/mL(P=0.025),50 μg/mL(P=0.000),and 100 μg/mL(P=0.049)groups compared to the control group.After 48 h,proliferation activity was significantly higher in the 6.25 μg/mL(P=0.024),12.5 μg/mL(P=0.006),25 μg/mL(P=0.000),50 μg/mL(P=0.000),and 100 μg/mL(P=0.000)groups compared to the control group.Cell cycle analysis revealed that,after 24 h of gingipain stimulation,the proportion of HN6 cells in the G1 phase decreased,while the proportion in the S+G2 phase significantly increased compared to the control group(25 μg/mL group:P=0.024;50 μg/mL group:P=0.001).Compared to the control group,the scratch assay demonstrated a significant increase in the percentage of scratch closure as the concentration of gingipain extract increased(P=0.001).Compared to the control group,the Transwell invasion assay showed a significant increase in the number of cells passing through the bottom of the chamber as the concentration of gingipain extract increased.RT-PCR and Western blotting results indicated that as the concentration of gingipain extract increased,the expression levels of N-cadherin mRNA and protein in HN6 cells significantly increased,while the expression levels of E-cadherin mRNA and protein significantly decreased compared to the control group.Conclusion·Gingipain extract could promote proliferation,migration,and invasion of oral squamous cell carcinoma HN6 cells.

Objective·To investigate and analyze periodontal health knowledge and behaviors in medical students and the relationship of these knowledge and behaviors with periodontal health status, and to determine the periodontal health level of this population. Methods·A total of 602 medical students were included in this cross-sectional epidemiological study. The questionnaire covered sociodemographic information, periodontal health-related behaviors and knowledge, experience about themselves, and periodontal health of parents, etc. Meanwhile, periodontal health indices of index teeth were examined, including probing depth (PD), clinical attachment loss (CAL), and bleeding on probing (BOP), etc. Results·Of 570 subjects aged 16-26 who completed the survey, 79.82% never used dental floss, and 78.25% never underwent periodontal debridement. 50.25% of the index teeth had BOP, and only 0.70% of the subjects had no BOP. 81.05% of the subjects had some degree of periodontal attachment loss. Male students were more susceptible to periodontitis (P=0.027) and gingivitis (P=0.012) than female students. Conclusion·No new risk factors affecting the periodontal health are identified. Regular periodontal cleaning and protection are important for young people to prevent periodontitis.

Objective · To observe short and medium term survival of implants in patients with chronic periodontitis after implantation. Methods · 54 patients with chronic periodontitis (133 implants) were enrolled from August 2011 to August 2013. The survival of implants was observed and the periimplant diseases were compared and analyzed between patients with different degrees of chronic periodontitis. Results · The 3-year survival rate of implants was 97.74%. The differences between patients with different degrees of chronic periodontitis were not statistically significant (P=0.452). Periodontal pocket depth (PPD) and modified plaque index (mPLI) were significantly higher in patients with severe chronic periodontitis than in patients with mild and moderate chronic periodontitis. For patients not receiving supportive periodontal therapy (SPT), the peri-implantitis rate in patients with severe chronic periodontitis was significantly higher than that in patients with mild and moderate chronic periodontitis (P=0.009). For smokers, the periimplantitis rate in patients with severe chronic periodontitis was significantly higher than that in patients with mild and moderate chronic periodontitis (P=0.016). Conclusion · For patients with chronic periodontitis, the theraputic effect of implant treatment is good. Plaque control, SPT, and smoking cessation can reduce the incidence of peri-implantitis.

Objective · To investigate the clinical effects of photo-activated disinfection (PAD)-assisted non-surgical therapy on the treatment of chronic periodontitis. Methods · Eleven patients with chronic periodontitis (totally 118 selected sites) were randomly enrolled. A split-mouth self-control method was adopted. Selected sites with the probing depth (PD) of bilateral homonymous teeth ≥ 5 mm were randomly assigned to the group A (receiving scaling and root planning, SRP) and the group B (receiving SRP+ PAD). Periodontal clinical indexes, inflammation indexes, and periodontal pathogens at selected sites were examined at baseline and 6 and 12 weeks after treatment. Results · Both SRP alone and SRP+PAD improved the periodontal inflammation significantly. The positive rate of bleeding on probing (BOP) 12 weeks after treatment was remarkably lower in the group B than in the group A (37.3% vs 57.6%, P=0.042). Both SRP and SRP+PAD effectively decreased matrix metalloproteinase-8 (MMP-8) and interleukin-1β (IL-1β) levels in gingival crevicular fluid. The IL-1β levels 6 and 12 weeks after treatment were significantly lower in the group B than in the group A [(17.99±14.26) pg/mL vs (32.64±30.69) pg/mL, P=0.007; (11.37±10.25) pg/mL vs (23.85±15.55) pg/mL, P=0.000]. Both treatments decreased the ratio of P. gingivalis and F.nucleatum in total bacteria. Conclusion · PAD can serve as a potential adjunctive therapy to conventional SRP in the treatment of chronic periodontitis with better improvement of bleeding gums and control of periodontal inflammation.

Objective: To study the expression of Survivin protein and its relationship with apoptosis in oromaxillofacial sarcoma(OMFS). Methods:The expression of Survivin protein and apoptosis were assessed by immunohistochemical staining and TUNEL method in 37 OMFS samples and 14 oral benign mesenchymal tumor(BMT) samples.Results:The Survivin positive rate in oromaxillofacial sarcomas was 81.08% and none in benign tumors(P