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Weak direct current (DC) exerts killing effect and synergistic killing effect with antibiotics in some specific bacteria biofilms. However, the potential of weak DC alone or combined with periodontal antibiotics in controlling periodontal pathogens and plaque biofilms remains unclear. The objective of this study was to investigate whether weak DC could exert the anti-biofilm effect or enhance the killing effect of metronidazole (MTZ) and/or amoxicillin-clavulanate potassium (AMC) on subgingival plaque biofilms, by constructing an in vitro subgingival plaque biofilm model.The pooled subgingival plaque and saliva of patients with periodontitis (n = 10) were collected and cultured anaerobically on hydroxyapatite disks in vitro for 48 h to construct the subgingival plaque biofilm model. Then such models were stimulated with 0 μA DC alone (20 min/12 h), 1000 μA DC alone (20 min/12 h), 16 μg/ml MTZ, 16 μg/ml AMC or their combination, respectively. Through viable bacteria counting, metabolic activity assay, quantitative real-time PCR absolute quantification and 16S rDNA sequencing analysis, the anti-biofilm effect of 1000 μA DC and enhanced killing effects of 1000 μA DC combined with antibiotics (MTZ, AMC or MTZ+AMC) were explored.The old subgingival plaque model (48 h) had no significant difference in total bacterial loads from subgingival plaque in situ, which achieved a similarity of 80%. The 1000 μA DC plus MTZ or AMC for 12 h showed a stronger synergistic killing effect than the same combination for 20 min. The metabolic activity was reduced to the lowest by DC plus MTZ+AMC, as 37.4% of that in the control group, while average synergistic killing effect reached 1.06 log units and average total bacterial loads decreased to 0.87 log units. Furthermore, the relative abundance of the genera Porphyromonas, Prevotella, Treponema_2, and Tannerella were decreased significantly.The presence of weak DC (1000 μA) improved the killing effect of antibiotics on subgingival plaque biofilms, which might provide a novel strategy to reduce their antibiotic resistance.

To examine the wear occurring in a group of new Gracey curettes due to the sharpening and scaling processes and record the number of service cycles before breakage.This study included 592 working ends of Gracey curettes that were subjected to cycles of sharpening and scaling. Three-dimensional measurements of the blades and the status of the working ends were recorded before and after each process.With an increase in the number of usage cycles, the three-dimensional measurements of the blades decreased. During this study, 184 working ends were broken, of which 38.59% were of #11/12 Gracey curettes, and only 8.15% were of #7/8 Gracey curettes. The average number of cycles required for the fracture of Gracey curettes was 14.34. Cox regression analyses showed that the factors influencing the survival cycles were the tip width before usage and the type of Gracey curette. Moreover, the sharpening process was responsible for approximately half of the total instrument wear. Among the four types of Gracey curettes, the #11/12 Gracey curettes showed the greatest amount of sharpening wear, accounting for50% of the total wear.The service life of Gracey curettes varies according to their types; the #11/12 Gracey curettes are more susceptible to breakage, while #7/8 Gracey curettes tend to have a long service life. Furthermore, the sharpening process was responsible for a considerable amount of curette wear.

Background: Porphyromonas gingivalis (P. gingivalis) is a pathogenic bacterium widely present in subgingival plaques of patients with periodontitis. It induces periodontitis with bone loss as its main feature by changing the number and composition of symbiotic microorganisms, as well as inducing the natural immune response of the host. However, the mechanism of the latter remains unclear. Objective: This study aims to investigate the effect of P. gingivalis lipopolysaccharide (LPS) on regulatory B cells (Breg) in the occurrence and development of periodontitis. Method: We detected the mRNA levels of IL-10 in B cells under the stimulation of P. gingivalis LPS and/or E. coli LPS, distinguished IL-10-producing cells from different B cell subgroups using flow cytometry. Through toll-like receptor (TLR) knockout mice, the role of TLR2 and TLR4 in this process was also evaluated. Results: Results showed that P. gingivalis stimulated B cells to produce IL-10 via TLR2/4. CD5+B1 subset is the main source of IL-10+Breg cell. Under P. gingivalis LPS stimulation, CD5+IgM+CD93-IL-10+B cell subset increased significantly, which was regulated through TLR2/ 4. Conclusion: The results of this study provides new insights into the immunopathogenic mechanism of P. gingivalis, preliminarily discussed the effect of P. gingivalis on the production of Breg, and present a theoretical foundation for subsequent investigations on the occurrence and development of periodontitis.

Background: Over the last decade, there has been an increasing number of clinical and laboratory evidence supporting associations between Polycystic ovary syndrome (PCOS) and periodontitis, but few studies have been conducted on the underlying mechanisms of the two diseases through the transcriptomic approach. In this study, gene co-expression networks between PCOS and periodontitis were analyzed by bioinformatics tools. Methods: PCOS and periodontitis expression data were downloaded from the GEO database, and the differentially expressed genes (DEGs) were identified. After obtaining Intersected genes, GO and KEGG pathway enrichment analysis and random forest (RF) algorithm were used to screen hub genes in PCOS and periodontitis. The functions of the hub genes were analyzed by GSEA, and the correlations between hub genes and immune infiltration in two diseases were examined. Furthermore, a TF-ceRNA regulatory network of hub genes was constructed. Results: There were 1,661 DEGs in PCOS and 701 DEGs in periodontitis compared to the controls. After overlapping, 66 intersected genes were shown to be involved in PCOS and periodontitis, and were mainly enriched in immune and inflammation-related biological processes and pathways. 40 common genes were selected from the PPI network constructed by STRING. The RF algorithm demonstrated that ACSL5, NLRP12, CCRL2, and CEACAM3 were hub genes in PCOS and periodontitis, and the GSEA result revealed their close relationship with the antigen processing and presentation, and chemokine signaling pathway. Moreover, the data showed that those 4 hub genes may serve as diagnostic genes for PCOS and periodontitis. Conclusion: This study identified ACSL5, NLRP12, CCRL2, and CEACAM3 as the diagnostic genes at the intersection of PCOS and periodontitis, and establish a ceRNA network, which could provide a molecular basis for future experimental studies on the association between PCOS and periodontitis.

This study was aimed to investigate the effects of temperature and ultrasonic scaler on infusion process of green tea leaves, and catechins stability under ultrasonic vibration in green tea infusion (GTI). (−)-epigallocatechin (EGC), (−)-epicatechin gallate (ECG), (−)-catechin (C), (+)-epicatechin (EC), (−)-epigallocatechin gallate (EGCG) and (−)-gallocatechin gallate (GCG) were measured with ultra-high performance liquid chromatography (UHPLC). Green tea leaves were infused with distilled water (1:50 w/v) for 0.5–24 h at 25 °C, and 15 min at 65 °C respectively. Meanwhile, the infusion process of same ratio was conducted for 2 h at 25 °C, with or without assistance of ultrasonic scaler. After filtration of tea leaves, the tip of ultrasonic scaler was immersed into GTI and vibrated at 33 kHz for 2 h. More amounts of EGC, ECG, C, EC could be obtained in GTI (24 h, 25 °C) compared to the contrast (15 min, 65 °C), meanwhile, the concentration of EGCG could achieve 966.5 ± 2.9 μg/mL which accounted for 97.6% of that in the contrast. During the infusion process for 2 h, catechins amount could be improved by 20.8–31.2% with the ultrasonic assistance. After filtration of tea leaves, the amount of total catechins in GTI could be increased by 4.7% under ultrasonic vibration. Our results indicate that a high-quality GTI could be prepared at 25 °C and the level of catechins achieve a plateau phase after 3 h. The ultrasonic scaler could accelerate the infusion process, and didn’t affect the catechins stability in GTI at 25 °C.

Periodontitis has been demonstrated to be bidirectionally associated with diabetes and has been recognized as a complication of diabetes. As a periodontal pathogen

Purpose To establish a digital assessment method for changes in gingiva morphology following initial periodontal therapy. Methods Ten periodontal-healthy participants were selected, and digital models obtained by intraoral scanning and digitizing conventional impressions. Using dentition as a reference, best fit alignment between digital models was carried out. Root mean square (RMS) was calculated to evaluate differences in models, and gingival volume discrepancy (GVD) was calculated after combining separated models. Trueness of intraoral scanning used on the gingiva was evaluated using RMS and GVD between intraoral and conventional models with conventional models as references; precision was evaluated among different intraoral models of one participant. Twenty-three periodontitis-affected participants underwent intraoral scanning immediately after supragingival scaling and two weeks after initial periodontal therapy. The GVD of gingiva between two digital models was calculated to assess gingival changes and related factors after therapy. Results Trueness of intraoral scanning used on the entire gingiva was 83.65 ± 14.43 μm; precision was 70.71 ± 25.58 μm; GVD error measured by digital models was 15.28 ± 10.00 mm³. Gingival volume in periodontitis-affected participants decreased 104.04-1155.09 mm³ after therapy. Probing depth, bleeding index, and keratinized gingival width positively correlated with changes in gingival volume. Conclusion Intraoral scanning can be recommended as a method of evaluating morphological changes in gingiva.

Understanding the mechanism of the differentiation of induced pluripotent stem cells (iPSCs) into mesenchymal stem cells (MSCs) and promoting the production efficiency of iPSC-derived MSCs (iPSC-MSCs) are critical to periodontal tissue engineering. However, the gene networks that control this differentiation process from iPSCs into MSCs are poorly understood. We demonstrated that

Periodontitis is a major cause of tooth loss in adults that initially results from dental plaque. Subgingival plaque pathogenesis is affected by both community composition and plaque structures, although limited data are available concerning the latter. To bridge this knowledge gap, subgingival plaques were obtained using filter paper (the fourth layer) and curette (the first-third layers) sequentially and the phylogenetic differences between the first-third layers and the fourth layer were characterized by sequencing the V3-V4 regions of 16S rRNA. A total of 11 phyla, 148 genera, and 308 species were obtained by bioinformatic analysis, and no significant differences between the operational taxonomic unit numbers were observed for these groups. In both groups, the most abundant species were Porphyromonas gingivalis and Fusobacterium nucleatum. Actinomyces naeslundii, Streptococcus intermedius, and Prevotella intermedia possessed relatively high proportions in the first-third layers; while in the fourth layer, both traditional pathogens (Treponema denticola and Campylobacter rectus) and novel pathobionts (Eubacterium saphenum, Filifactor alocis, Treponema sp. HOT238) were prominent. Network analysis showed that either of them exhibited a scale-free property and was constructed by two negatively correlated components (the pathogen component and the nonpathogen component), while the synergy in the nonpathogen component was lower in the first-third layers than that in the fourth layer. After merging these two parts into a whole plaque group, the negative/positive correlation ratio increased. With potential connections, the first-third layers and the fourth layer showed characteristic key nodes in bacterial networks.

To evaluate the integrated efficacy of completely simultaneous ultrasonic scaling and subgingival irrigation with chlorhexidine in chronic periodontitis.This was a split-mouth randomized controlled trial including 19 patients with moderate to severe chronic periodontitis. After calculus removal, the test side received simultaneous ultrasonic scaling and subgingival irrigation with 0.12% chlorhexidine, and the control side received simultaneous ultrasonic scaling and subgingival irrigation with distilled water. A newly designed ultrasonic scaler tip with a liquid outlet on the terminal was used. Clinical parameters were assessed, and gingival crevicular fluid was collected before treatment at baseline and 1.5, 3, and 6 months after baseline.On follow-up, both sides showed significant reductions in clinical parameters and concentration of inflammatory mediators in gingival crevicular fluid. Adjunct application of CHX resulted in an additional periodontal pocket reduction (0.27 to 0.29 mm, P.05) compared to the control side, in sites with initial probing depth of 4 to 5 mm. Within the initial probing depth ≥ 6 mm, the additional probing depth reduction was 0.44 to 0.60 mm (P.05), with clinical attachment loss, concentration of interleukin-6, and concentration of matrix metalloproteinase-8 being 0.32 to 0.38 mm, 2.64 to 3.40 µg/L, and 19.78 to 22.39 ng/L, respectively (all P.05).In this study, treatment outcomes of chronic periodontitis could be improved by treating the root surface with simultaneous ultrasonic scaling and chlorhexidine irrigation. The adjunctive use of 0.12% chlorhexidine with a newly designed ultrasonic scaler tip in the treatment of moderate to severe chronic periodontitis demonstrated significant clinical benefits and decrease in inflammatory mediator when compared with scaling and root planing plus placebo.

Background Mitofusin-2 (MFN2) is a kind of GTPase that participates in the regulation of mitochondrial fusion, which is related to a variety of physiological and pathological processes, including energy metabolism, cell differentiation, and embryonic development. However, it remains unclear whether MFN2 is involved in the metabolism and osteogenic differentiation of mesenchymal stem cells (MSCs). Methods MFN2 knockdown (MFN2-KD) and MFN2-overexpressing (MFN2-OE) induced pluripotent stem cell-derived mesenchymal stem cells (iPSC-MSCs) were constructed by lentivirus. The commercial kits were utilized to detect the glycolysis and oxidative phosphorylation (OXPHOS) rate. Flow cytometry, Western blot, quantitative real-time polymerase chain reaction (qRT-PCR), RNA-seq, immunofluorescence, and immunoprecipitation were employed for phenotype and molecular mechanism assessment. Results We demonstrated that MFN2 and Wnt/β-catenin signaling pathway regulated glycolysis of iPSC-MSCs. The lack of MFN2 promoted the osteogenic differentiation of iPSC-MSCs, and aerobic glycolysis in the presence of sufficient oxygen, which increased glucose consumption and lactic acid production, as well as the glycolytic enzyme activity and gene expression. Inhibiting the Wnt/β-catenin signaling pathway normalized the enhanced glycolytic rate and osteogenic differentiation of MFN2-KD iPSC-MSCs. MFN2-OE iPSC-MSCs displayed the opposite phenotype. Conclusions Downregulating MFN2 promotes osteogenic differentiation of iPSC-MSCs through aerobic glycolysis mediated by the Wnt/β-catenin signaling pathway. Our research reveals the new function of MFN2 in regulating the osteogenic differentiation and energy metabolism of MSCs, which will provide a new therapeutic target and theoretical basis for alveolar bone repair and periodontal regenerative treatment.

Wenmin Zeng,1 Guojing Liu,1 Qingxian Luan,1 Chunyu Yang,1 Shiyi Li,1 Xiaoqian Yu,1 Li Su2 1Department of Periodontology, Peking University School and Hospital of Stomatology, Beijing, People’s Republic of China; 2Center of Medical and Health Analysis, Peking University, Beijing, People’s Republic of ChinaCorrespondence: Xiaoqian YuDepartment of Periodontology, Peking University School and Hospital of Stomatology, Beijing, 100081, People’s Republic of ChinaEmail Y_PK@163.comLi SuCenter of Medical and Health Analysis, Peking University, Beijing, 100191, People’s Republic of ChinaEmail lisu76@bjmu.edu.cnObjective: Periodontitis, one of the most prevalent chronic oral infectious diseases in humans, is induced by the breakdown in the balance between the biofilm and host immune system. Previous studies have shown the presence of large numbers of B cells in periodontitis lesions, implicating that B lymphocytes play a predominant role during the pathogenesis of periodontitis. This study aimed to investigate the role of all B cells in the initiation of periodontitis.Methods: Experimental periodontitis was induced in B cell-deficient (CD19Cre) mice and wild-type (WT) control mice by 5-0 silk ligation around the maxillary second molar. Four weeks after ligation, alveolar bone loss was determined by micro-computed tomography. The levels of inflammatory cytokines and receptor activator of NF-κB ligand (RANKL)/osteoprotegerin in periodontal lesions were analyzed using real-time quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, and immunohistochemistry. Lymphocyte populations in the cervical lymph nodes and spleen and among the peripheral blood mononuclear cells were detected by flow cytometry.Results: B-cell deficiency resulted in increased severity of alveolar bone loss in mouse experimental periodontitis, which was associated with increased osteoclast activity and upregulated RANKL expression in the periodontal lesions. In addition, gingiva cytokine expression profiles were shifted to T helper type 1 (Th1) and Th17 in the CD19Cre mice with ligature-induced periodontitis compared with WT mice. In addition, a reduced CD4+/CD8+ T cell ratio was observed in the CD19Cre mice.Conclusion: B-cell deficiency exacerbates the inflammation and alveolar bone loss in ligature-induced experimental periodontitis in mice, implicating that B cells may overall play a protective role in the initiation of periodontitis.Keywords: periodontitis, experimental periodontitis, alveolar bone loss, B lymphocytes

Elevated p53 promotes oxidative stress and production of pro-inflammatory cytokines in liposaccharide (LPS)-treated healthy human gingival fibroblasts (HGFs). This study compared oxidative stress, production of inflammatory cytokines, and p53 expression in HGFs from patients with chronic periodontitis (CP) and healthy subjects in vitro upon LPS from Porphyromonas gingivalis challenge.Human gingival fibroblasts were isolated from 6 biopsies-3 from healthy donors and 3 from diseased area in CP (Grade B, Stage III). HGFs were cultured with or without 1 μg/ml 24 h LPS. Oxidative stress was assessed by analyzing the level of reactive oxygen species (ROS). Mitochondrial membrane potential and respiration were determined by immunofluorescence and respirometry, respectively. Tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β were determined by enzyme-linked immunosorbent assay. P53 expression was monitored by Western blot and immunofluorescence.Human gingival fibroblasts from CP exhibited increased levels of mitochondrial p53, enhanced ROS production, decreased mitochondrial membrane potential, increased mitochondrial oxygen consumption, and increased secretion of TNF-α, IL-6, and IL-1β, as compared to HGFs from healthy donors. Moreover, LPS exacerbated these changes.Human gingival fibroblasts from CP exhibited stronger basal and LPS-inducible oxidative stress and inflammatory response as compared to HGFs from healthy subjects by increased p53 in mitochondria.

The aim of this study was to clinically and histologically evaluate the efficacy of using acellular dermal matrix (ADM) for peri-implant vertical soft tissue augmentation at implant placement.Twenty patients were enrolled in this study. According to the initial thickness of vertical soft tissue, patients were assigned into the ADM group (≤2 mm) or the control group (2 mm) prior to implant surgery +ADM grafting or implant surgery alone. Second-stage surgery was carried out 3 months later, and a small piece of ridge membrane was harvested for histological and immunohistochemical evaluation. Vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF)-BB in peri-implant crevicular fluid (PICF) were also assessed 1 week, 1 month, and 5 months after second-stage surgery. Clinical parameters were recorded to evaluate peri-implant health at 1 week and 3 months after implant restoration.All 20 implants healed uneventfully and successfully. Soft tissue thicknesses were comparable in the two groups at second-stage surgery (3.20 ± 0.42 mm vs. 3.50 ± 0.58 mm). In the ADM group, the mean increase in soft tissue thickness was 1.85 ± 0.34 mm. Histological and immunohistochemical outcomes showed no differences between the two groups. VEGF and PDGF-BB levels in PICF were significantly lower in the ADM group 1 week after second-stage surgery (p .01), yet they decreased in both groups later. The difference between the groups had disappeared by 5 months after second-stage surgery. The clinical peri-implant parameters were good and stable by the end of the study (3 months after restoration).Our results suggested that using ADM at implant placement was effective in increasing the thickness of peri-implant vertical soft tissue and achieved comparable clinical and histological performance to the control group. However, the incremental soft tissue showed inferior angiogenic ability in the early stage of wound healing.

BACKGROUND AND OBJECTIVE The abnormal structure and function of mitochondria in cells is closely associated with inflammatory diseases. However, the physiology of mitochondria within gingival tissues and human gingival fibroblasts (HGFs) in patients with chronic periodontitis (CP) remains unclear. The objective of this study was to investigate the structure profile and function of mitochondria in gingival tissues and in HGFs derived from patients with or without CP. These features of mitochondria in HGFs were further analyzed when HGFs were induced by lipopolysaccharide (LPS) from Porphyromonas gingivalis (P.g). METHODS Gingival tissues and HGFs were collected from CP and healthy patients. Mitochondrial structure was assessed by transmission electron microscopy. Tissues or cells lysis was performed for mitochondrial DNA (mtDNA) quantification, and real-time polymerase chain reaction (RT-PCR) tests were used to determine mtDNA copy numbers. Western blot analysis was used to evaluate autophagy-related protein (ATG)-5, microtubule-associated protein light chain 3 (LC3), and mitochondrial matrix protein pyruvate dehydrogenase kinase isozyme 2 (PDK2) levels in tissues and HGFs from CP and healthy individuals. RESULTS Tissues and HGFs from CP showed a significant greater mitochondrial structure destruction, lower mtDNA level, increased ATG5, LC3-II, and lower PDK2 protein levels than those of healthy individuals. In addition, LPS from P.g also triggered the same results in HGFs from healthy donors. Moreover, the challenge of HGFs from CP with LPS worsened these parameters. CONCLUSION Mitochondrial structure and function within gingival tissues and HGFs from CP individuals were abnormal compared to those from healthy donors, and LPS could promote mitochondrial destruction.

Background/purpose Research into biomaterial alternatives to connective tissue grafts (CTG) is a research hotspot. The purpose of this clinical trial was to compare the effectiveness of root coverage through tunnel technique with concentrated growth factor (CGF) vs CTG in treating multiple gingival recessions using digital measurements. Materials and methods Seventy Cairo Class I multiple gingival recessions (in 28 patients) were treated with either CGF or CTG combined with coronally advanced tunnel technique. Digital models were obtained at baseline, 2 weeks, 6 weeks, and 6 months post-op to compare the gain in gingival height, area, volume, and thickness. Tooth sensitivity, post-operative pain, and healing index were also recorded. Results Complete root coverage at 6 months post-op were 47.06% in the CGF group and 77.78% in the CTG groups. Mean root coverages were 80.55% and 96.18%, respectively. No statistical difference was demonstrated between the two groups in terms of gingival area gain at 2 weeks post-op, but the CTG group had greater increases in gingival height, area, volume, and thickness in the period after 2 weeks post-op. Pain scores were statistically significantly lower in the CGF group. At 6 months post-op, sensitivity scores decreased more significantly in the CTG group. Conclusion Digital measurements revealed post-operative gingival shrinkage was more pronounced in the CGF group than in the CTG group when combined with coronally advanced tunnel technique. Despite the ease-of-use and minimal post-operative discomfort, it is difficult to achieve similar root coverage outcomes to CTG when using CGF alone in treating multiple gingival recessions.

Skeletal Class II malocclusion is a complex orofacial condition. Here, we translated the single clinical problem to a multidisciplinary approach that combined the periodontal surgery, biomaterial implantation, and orthodontics to treat this condition. This study aimed to explore the clinical effectiveness of modified periodontally accelerated osteogenic orthodontics (PAOO) in adult patients with skeletal Class II discrepancy via a camouflage orthodontic approach. This clinical trial has been registered in the Chinese Clinical Trial Registry (trial number: ChiCTR2100052638, trial URL: http://www.chictr.org.cn/showproj.aspx?proj=135827). A total of 26 adult female patients with similar skeletal Class II malocclusions and similar dental and skeletal discrepancies were enrolled. A total of 13 patients in the experimental group received modified PAOO characterized by vertical incisions in interradicular areas and random punching made by a piezoelectric device, whereas 13 patients in the control group received orthodontic treatment only. All patients underwent extraction of four premolars and orthodontic treatment with the sliding MBT straight-wire technique. Treatment courses were recorded and changes in dental and skeletal parameters were evaluated by cephalometric analysis and translated into upper digital cast for further measurements. The results showed that the durations of the alignment and leveling stage (4.51±1.53 mos versus 9.41±1.46 mos. P

Mitofusin 2 (MFN2) is a regulatory protein participating in mitochondria dynamics, cell proliferation, death, differentiation, and so on. This study aims at revealing the functional role of MFN2 in the pluripotency maintenance and primitive differetiation of embryonic stem cell (ESCs). A dox inducible silencing and routine overexpressing approach was used to downregulate and upregulate MFN2 expression, respectively. We have compared the morphology, cell proliferation, and expression level of pluripotent genes in various groups. We also used directed differentiation methods to test the differentiation capacity of various groups. The Akt signaling pathway was explored by the western blot assay. MFN2 upregulation in ESCs exhibited a typical cell morphology and similar cell proliferation, but decreased pluripotent gene markers. In addition, MFN2 overexpression inhibited ESCs differentiation into the mesendoderm, while MFN2 silencing ESCs exhibited a normal cell morphology, slower cell proliferation and elevated pluripotency markers. For differentiation, MFN2 silencing ESCs exhibited enhanced three germs' differentiation ability. Moreover, the protein levels of phosphorylated Akt308 and Akt473 decreased in MFN2 silenced ESCs, and recovered in the neural differentiation process. When treated with the Akt inhibitor, the neural differentiation capacity of the MFN2 silenced ESCs can reverse to a normal level. Taken together, the data indicated that the appropriate level of MFN2 expression is essential for pluripotency and differentiation capacity in ESCs. The increased neural differentiation ability by MFN2 silencing is strongly related to the Akt signaling pathway.

Low electric current can inhibit certain microbial biofilms and enhance the efficacy of antimicrobials against them. This study investigated the electricidal and bioelectric effects of direct current (DC) against Porphyromonas gingivalis biofilms as well as the underlying mechanisms. Here, we firstly showed that DC significantly suppressed biofilm formation of P. gingivalis in time- and intensity-dependent manners, and markedly inhibited preformed P. gingivalis biofilms. Moreover, DC enhanced the killing efficacy of metronidazole (MTZ) and amoxicillin with clavulanate potassium (AMC) against the biofilms. Notably, DC-treated biofilms displayed upregulated intracellular ROS and expression of ROS related genes (sod, feoB, and oxyR) as well as porin gene. Interestingly, DC-induced killing of biofilms was partially reversed by ROS scavenger N-dimethylthiourea (DMTU), and the synergistic effect of DC with MTZ/AMC was weakened by small interfering RNA of porin gene (si-Porin). In conclusion, DC can exert electricidal and bioelectric effects against P. gingivalis biofilms partially via promotion of oxidative stress and antibiotic transport, which offers a promising approach for effective management of periodontitis.

Background The aim of this study is to investigate three-dimensional quantitative analysis of buccal augmented tissue alterations after surgery using a modified coronally advanced tunnel (MCAT) technique combined with a de-epithelialized gingival graft (DGG) within 1 year post-op, based on intraoral scanning. Methods 25 Cairo class I gingival recession defects were treated using an MCAT technique with DGG. Digital impressions were taken using an intraoral scanner at baseline, 2 weeks, 6 weeks, 3 months, and 1 year after the surgery. Three-dimensional quantitative measurements within 1 year were analyzed for buccal augmented tissue after surgery, including postoperative gingival height gain (GHG), area gain (GAG), volume gain (GVG) and mean thickness (GMT) of region of interest, as well as the tissue thickness change at 1, 2, and 3 mm (TTC1, TTC2, and TTC3) apical to the cemento-enamel junction. Results Postoperative GHG, GAG, GVG, and GMT were distinctly encountered at 2 weeks post-op, then gradually decreased. At 1 year, GHG, GAG, GVG, and GMT were 2.211 ± 0.717 mm, 7.614 ± 2.511 mm2, 7.690 ± 4.335 mm3 and 0.965 ± 0.372 mm, respectively. Significant decreases were recorded between 6 weeks and 1 year in terms of GHG, GAG, and GVG. The GMT was sustained after 6 weeks with an increase of nearly 1 mm at 1 year. TTC1 and TTC2 yielded thicker tissue change than TTC3. Conclusions Three-dimensional quantitative measurements taken via intraoral scanning showed that buccal augmented tissue acquired via MCAT with DGG tends to be stable after 3 months post-op. Digital measurement can be applied in periodontal plastic surgery as a clinically feasible and non-invasive evaluation method for achieving volumetric outcomes. Trial registration This study was retrospectively registered in the Chinese Clinical Trial Registry: ChiCTR1900026768. Date of registration: 21/10/2019.

The present study aimed to investigate whether gingival fibroblasts (GFs) of patients with aggressive periodontitis (AgP) are more sensitive to lipopolysaccharide (LPS) stimulation than GFs of control subjects. AgP causes rapid periodontal destruction, including the production of cytokines [i.e. interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α] and matrix metalloproteinases (MMP)-1, -3 and -9 in AgP GFs. LPS upregulates IL-1β, IL-6, TNF-α, MMP-1, MMP-3, MMP-9 and mitochondrial reactive oxygen species (mtROS). Fibroblasts are known to be associated with immune responses to bacterial virulence factors, but the precise mechanisms underlying this severe periodontal disease are unclear. In the present study, primary human GFs of four patients with AgP and four healthy subjects were challenged in vitro with LPS from Porphyromonas gingivalis (P. gingivalis). The generation of mtROS in GFs was assessed using MitoSOX Red. The expression of genes encoding inflammatory cytokines and MMPs in GFs was analyzed using reverse transcription-quantitative polymerase chain reaction, and the expression of proteins was analyzed using ELISA and Western blotting. Human GFs of patients with AgP exhibited higher levels of mtROS, and higher mRNA and protein expression levels of proinflammatory cytokines, including IL-1β, IL-6, MMP-1, MMP-3 and MMP-9 compared with healthy human GFs following stimulation with LPS from P. gingivalis. In the present study, it was demonstrated that GFs of patients with AgP display hyperreactivity when challenged with LPS.

Background (−)-Epigallocatechin Gallate (EGCG) as green tea catechins possessed antibacterial and anti-inflammatory effects on periodontal disease. This study was designed to evaluate the clinical and microbiological efficacy of scaling and root planing (SRP) using EGCG aqueous solution as coolants through a new-type ultrasonic scaler tip on chronic periodontitis. Methods This split-mouth, randomized clinical trial included 20 patients (2 drop-outs) with chronic periodontitis and the maxillary contra-lateral sides were allocated into test and control groups randomly. Through the new-type scaler tip, 762 sites with probing depth (PD) ≥ 4 mm were treated by SRP using EGCG solution or distilled water as coolants respectively. Clinical parameters and red complex pathogens in subgingival microbiome were evaluated at baseline, 3 and 6 months after treatments. Results During 6 months, the SRP plus EGCG medication contributed to additional PD reduction as 0.33 mm and gain of clinical attachment level as 0.3 mm compared with SRP alone, and approximate 8% more sites obtained PD reduction ≥ 2 mm (p Tannerella forsythia was significantly lower in the combined treatment group (p Conclusion The purified EGCG showed the potential to improve the outcome of periodontal non-surgical treatment and the new-type scaler tip provided an alternative vehicle for subgingival medication. Trial registration The trial was registered in Chinese Clinical Trial Registry on 15 February 2020 (No.: ChiCTR2000029831, retrospectively registered). http://www.chictr.org.cn/showprojen.aspx?proj=49441.

Background: The aim of this study to investigate three-dimensional quantitative analysis buccal augmented tissue alterations after modified coronally advanced tunnel (MCAT) technique combined with subepithelial connective tissue graft (SCTG) within 1-year based on intraoral scanning.Methods: 25 Cairo class I gingival recession defects were treated by MCAT technique with SCTG. Two examiners performed digital three-dimensional measurements, including the preoperative gingival recession height (GH), width (GW) and root exposed area (REA), postoperative gingival height gain (HG), area gain (AG), volume gain (VG) and mean thickness gain (MTG) of region of interest (ROI). Then, dynamic alterations of ROI and buccal tissue at 2 weeks, 6 weeks, 3 months and 1-year post-op were analysis. Results: Intra-class correlation coefficients (ICC) showed almost perfect inter-examiner reliability for digital measurement (ICC > 0.89). Postoperative HG, AG, VG and MTG were encountered distinct at 2 weeks post-op, then gradually decreased. At 1-year, AG, VG and MTG were 7.614 ± 2.511mm2, 7.690 ± 4.335mm3 and 0.965±0.372mm, respectively. Significant decreases were recorded between 6 weeks and 1-year in terms of HG, AG and VG. The MTG was sustained after 6 weeks with an increase of nearly 1mm at 1-year.Conclusions: Digital measurement by intraoral scanning offered an advantage of clinically feasible, non-invasive and reliable evaluation method for achieving volumetric outcomes after periodontal plastic surgery. Augmented tissue acquired by MCAT with SCTG tends to be stable after 3 months post-op.Trial registration：This study was retrospectively registered in Chinese Clinical Trial Registry: ChiCTR1900026768. Date of registration: 21/10/2019.