Impact of body mass index and polycystic ovary syndrome (PCOS) subtypes on periodontal health in Chinese women with PCOS and periodontitis.

BACKGROUND: This study aimed to investigate the impact of body mass index (BMI) and Polycystic Ovary Syndrome (PCOS) subtypes on periodontal parameters in Chinese women with PCOS and periodontitis. METHOD: We conducted a retrospective case-control study analyzing data from 88 women with PCOS and 82 healthy controls. Participants were categorized by BMI (<24.0 kg/m2and ≥24.0 kg/m2) and PCOS subtypes. We compared periodontal parameters [including probing depth (PD), gingival bleeding index (GBI)] and reproductive hormone-related parameters. RESULTS: Women with PCOS and periodontitis had a significantly higher GBI (2.71 ± 0.53) compared to controls (2.25 ± 0.41, p < 0.0001). Among patients with BMI <24.0 kg/m2, those with PCOS had a younger age [25.00(5.00) vs. 26.00(6.00) years, p < 0.05], lower PD [3.24(0.55) mm vs. 3.43 (0.48) mm, p < 0.01], and higher GBI [2.63(0.76) vs. 2.23(0.55), p < 0.0001]. For BMI ≥24.0 kg/m2, PCOS patients had a higher GBI [2.91(0.36) vs. 2.38(0.59), p < 0.01] but a lower percentage of severe periodontal disease (p < 0.05). CONCLUSION: PCOS could potentially worsen gingival inflammation among women already suffering from periodontitis, and a higher BMI might further intensify this correlation.

Nomogram prediction for periodontitis in Chinese pregnant women with different sociodemographic and oral health behavior characteristics: a community-based study.

BACKGROUND: Periodontitis is associated with poor pregnancy outcomes, indicating periodontal health as an important health concern for pregnant women. Herein, this study identified risk indicators for periodontitis and developed a nomogram for predicting the risk of periodontitis in pregnancy by analyzing periodontitis and associated factors in pregnant women. MATERIALS AND METHODS: A community-based cross-sectional study was conducted by including 438 pregnant women at 10-36 gestational weeks from Langfang, China. Pregnant women were examined for periodontal status, and their demographic, socioeconomic, and oral health behavior data were collected. Potential influencing factors of periodontitis were analyzed with univariate and multivariate logistic regression analyses. A nomogram was developed, followed by the assessment of its validation and discriminatory abilities. RESULTS: The prevalence of periodontitis was 59.8% in pregnant women. Periodontitis-associated variables in pregnant women were gestational age, non-first pregnancy, daily tooth brushing frequency of ≤ 1 before pregnancy, and annual frequency of periodontal treatment < 1 (including no periodontal treatment). The risk of periodontitis was positively associated with gestational age (OR = 1.28, 95% CI = 1.17-1.39, p < 0.001). Pregnancy history showed a strong positive association (OR = 6.57, 95% CI = 1.22-35.43, p = 0.03). Daily tooth brushing frequency before pregnancy was also positively associated with periodontitis (OR = 1.54, 95% CI = 1.03-2.79, p = 0.05). Additionally, the annual frequency of periodontal treatment exhibited a positive association, with higher odds observed for those with less frequent treatment (OR = 2.28, 95% CI = 1.25-4.14, p = 0.05; OR = 7.37, 95% CI = 3.04-22.06, p < 0.001). These four factors were used to develop a nomogram for predicting periodontitis in pregnant women. The area under the receiver operating characteristic curve of the nomogram was 0.855 and 0.831 in the training and testing cohorts, respectively, reflecting the superior prediction accuracy of the nomogram. The calibration curve and decision curve analysis demonstrated the good performance and net benefit of the nomogram. CONCLUSION: Risk factors for periodontitis in pregnant Chinese women include gestational age, non-first pregnancy, lower frequency of daily tooth brushing before pregnancy, and lower frequency of periodontal treatment. An easy-to-use nomogram with acceptable accuracy can allow for the prediction of periodontitis risk in pregnant Chinese women. CLINICAL RELEVANCE: With the assistance of this nomogram, clinicians can evaluate the risk of periodontitis in pregnancy, thereby offering more tailored oral health education to women of reproductive age.

Combined Periodontal-Orthodontic Treatment with Periodontal Corticotomy Regenerative Surgery in an Adult Patient Suffering from Periodontitis and Skeletal Class II Malocclusion: A Case Report with 5-Year Longitudinal Observation.

A thick periodontal phenotype with thick gingiva and alveolar bone volume is required for safe orthodontic tooth movement and long-term stability. A high incidence of dehiscence and fenestration in the labial aspect of mandibular anterior teeth may limit the correction of deformity and orthodontic treatment, especially when the lower anterior teeth are needed to have a large range of movement. This study reports a combination of periodontal therapy and orthodontic therapy with periodontal corticotomy regenerative surgery (PCRS) in a 25-year-old patient suffering from skeletal Class II malocclusion and periodontitis. The patient received periodontal therapy 5 years ago and commenced orthodontic treatment 4.5 years ago. During the 4 years of follow-up for PCRS, the clinical and radiographic evaluations revealed significant improvements in the periodontal phenotype of the mandibular anterior region. The periodontal phenotypes in the mandibular incisors region were all modified from thin to thick. Supplementing orthodontic treatment with labial PCRS could be a promising treatment strategy to maintain long-term periodontal health in adult patients with alveolar deficiency and thin gingiva tissue.

Effect of an extraoral scavenging device on eliminating droplets and aerosols generated in ultrasonic supragingival scaling: A randomised clinical trial.

OBJECTIVES: Ultrasonic scaling is extensively applied as part of the initial therapy for periodontal diseases, which has been restricted since the outbreak of the COVID-19 pandemic due to droplets and aerosols generated by ultrasonic devices. An extraoral scavenging device (EOS) was designed for diminishing droplets and aerosols in dental clinics. The objective of this study is to evaluate the effect of EOS on eliminating droplets and aerosols during ultrasonic supragingival scaling. METHODS: This single-blinded, randomised controlled clinical trial enrolled 45 patients with generalised periodontitis (stage I or II, grade A or B) or plaque-induced gingivitis. The patients were randomly allocated and received ultrasonic supragingival scaling under three different intervention measures: only saliva ejector (SE), SE plus EOS and SE plus high-volume evacuation (HVE). The natural sedimentation method was applied to sample droplets and aerosols before or during supragingival scaling. After aerobic culturing, colony-forming units (CFUs) were counted and analysed. RESULTS: Compared with the level before treatment, more CFUs of samples throughout treatment could be obtained at the operator's chest and the patient's chest and the table surface when using SE alone (p < 0.05). Compared with the SE group, the SE + EOS group and the SE + HVE group obtained decreasing CFUs at the operator's chest and the patient's chest (p < 0.05), while no significant difference was determined between these two groups. CONCLUSIONS: The EOS effectively eliminated splatter contamination from ultrasonic supragingival scaling, which was an alternative precaution for nosocomial contamination in dental clinics.

E2A regulates neural ectoderm fate specification in human embryonic stem cells.

E protein transcription factors are crucial for many cell fate decisions. However, the roles of E proteins in the germ-layer specification of human embryonic stem cells (hESCs) are poorly understood. We disrupted the TCF3 gene locus to delete the E protein E2A in hESCs. E2A knockout (KO) hESCs retained key features of pluripotency, but displayed decreased neural ectoderm coupled with enhanced mesoendoderm outcomes. Genome-wide analyses showed that E2A directly regulates neural ectoderm and Nodal pathway genes. Accordingly, inhibition of Nodal or E2A overexpression partially rescued the neural ectoderm defect in E2A KO hESCs. Loss of E2A had little impact on the epigenetic landscape of hESCs, whereas E2A KO neural precursors displayed increased accessibility of the gene locus encoding the Nodal agonist CRIPTO. Double-deletion of both E2A and HEB (TCF12) resulted in a more severe neural ectoderm defect. Therefore, this study reveals critical context-dependent functions for E2A in human neural ectoderm fate specification.

Weak direct current exerts synergistic effect with antibiotics and reduces the antibiotic resistance: An in vitro subgingival plaque biofilm model.

BACKGROUND AND OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Oxidative stress in human gingival fibroblasts from periodontitis versus healthy counterparts.

OBJECTIVE: 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. METHODS: 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-1ß were determined by enzyme-linked immunosorbent assay. P53 expression was monitored by Western blot and immunofluorescence. RESULTS: 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-1ß, as compared to HGFs from healthy donors. Moreover, LPS exacerbated these changes. CONCLUSION: 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.

Association of carotid intima-media thickness with periodontitis may depend on glycemic control.

BACKGROUND: There is evidence indicating that atherosclerosis is associated with periodontitis, especially in those with diabetes. The purpose of the present study was to determine whether glycemic control influences such association. METHODS: Cross-sectional data on 214 patients diagnosed with type 2 diabetes mellitus were obtained including results of basic laboratory tests, a periodontal examination, and carotid measurements. The association of periodontal parameters and carotid intima-media thickness (cIMT) or carotid plaque (CP) was evaluated in subgroups. RESULTS: Mean cIMT was significantly correlated with mean PLI, mean BI or number of PD ≥4 mm in the whole sample and the group with poor glycemic control. In the group with good glycemic control, however, only the number of PD ≥4 mm was associated with mean cIMT. A multiple logistic regression analysis also revealed that each 1 increase in mean PLI, mean BI or number of PD ≥4 mm was correlated with an increased cIMT in the whole sample. CONCLUSIONS: In addition to confirming the relationship between periodontitis and atherosclerosis, our study found a stronger association in groups with poor glycemic control compared to those with good glycemic control, suggesting that blood glucose modifies the association between periodontitis and arterial injury.

Efficacy of concentrated growth factor (CGF) in the surgical treatment of oral diseases: a systematic review and meta-analysis.

BACKGROUND: Concentrated growth factor (CGF), a new autologous platelet concentrate, has been widely investigated to the adjunctive treatment of oral diseases. This study aims to evaluate the efficacy of CGF in the surgical treatment of oral diseases. METHODS: MEDLINE, Web of Science, Scopus, Cochrane, and EMBASE databases were searched up to July 2023. Only randomized clinical trials were included. The methodologic quality was evaluated by the Cochrane Risk of Bias Tool. RevMan 5.4 software was used for data analysis. RESULTS: In the treatment of periodontal intrabony defects, bone graft combined with CGF was significantly superior to bone graft (P < 0.01), with mean intrabony defect depth reduction of 1.41 mm and mean clinical attachment level gain of 0.55 mm. In the regenerative surgery of furcation defects, the effect of CGF group was significantly better than control group (P < 0.0001), with mean probing depth reduction of 0.99 mm, vertical bone gain of 0.25 mm, and horizontal bone gain of 0.34 mm. CGF combined with coronally advanced flap (CAF) was more effective than CAF alone (mean keratinized tissue width increase of 0.41 mm, mean gingival thickness increase of 0.26 mm, P < 0.00001), but less effective than connective tissue graft (CTG) combined with CAF (mean root coverage difference of -15.1%, mean gingival thickness difference of -0.5 mm, P < 0.0001). In the alveolar ridge preservation, additional use of CGF reduced horizontal bone resorption by 1.41 mm and buccal vertical bone resorption by 1.01 mm compared to control group (P < 0.0001). The VAS score of CGF group was significantly lower than that of the control group at the 1st and 7th day after oral surgery (P < 0.0001). CONCLUSIONS: CGF can exert a positive adjunctive effect for the regenerative surgery of periodontal intrabony defects, furcation defects, and alveolar ridge preservation procedure. CGF combined with CAF has a better therapeutic effect on gingival recession compared to CAF alone, although it is not as effective as CTG combined with CAF. CGF could promote postoperative healing and pain relief in oral surgery within a week. There is currently not enough evidence to support the clinical benefits of CGF in other oral surgeries.

Abnormal mitochondrial structure and function are retained in gingival tissues and human gingival fibroblasts from patients with chronic periodontitis.

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.

Clinical and histological evaluation of the use of acellular dermal matrix (ADM) membrane in peri-implant vertical soft tissue augmentation: A controlled clinical trial.

OBJECTIVES: 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. MATERIALS AND METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.

Effect of partial restorative treatment on stress distributions in non-carious cervical lesions: a three-dimensional finite element analysis.

BACKGROUND: Partial restoration combined with periodontal root coverage surgery can be applied to the treatment of non-carious cervical lesions (NCCLs) accompanied with gingival recessions in clinical practice. However, the feasibility of NCCL partial restorative treatment from a biomechanical perspective remains unclear. This study aimed to investigate the effect of partial restorations on stress distributions in the NCCLs of mandibular first premolars via three-dimensional finite element analysis. METHODS: Three-dimensional finite element models of buccal wedge-shaped NCCLs in various locations of a defected zenith (0 mm, 1 mm, and 2 mm) were constructed and divided into three groups (A, B, and C). Three partially restored NCCL models with different locations of the lower restoration border (1 mm, 1.5 mm, and 2 mm), and one completely restored NCCL model were further constructed for each group. The following restorative materials were used in all restoration models: composite resin (CR), glass-ionomer cement (GIC), and mineral trioxide aggregate (MTA). The first principal stress distributions under buccal oblique loads of 100 N were analyzed. Restoration bond failures were also evaluated based on stress distributions at dentin-restoration interfaces. RESULTS: When the partial restoration fully covered the defected zenith, the first principal stress around the zenith decreased and the maximum tensile stress was concentrated at the lower restoration border. When the partial restoration did not cover the defected zenith, the first principal stress distribution patterns were similar to those in unrestored models, with the maximum tensile stress remaining concentrated at the zenith. As the elastic modulus of the restorative material was altered, the stress distributions at the interface were not obviously changed. Restoration bond failures were not observed in CR, but occurred in GIC and MTA in most models. CONCLUSIONS: Partial restorations that fully covered defected zeniths improved the stress distributions in NCCLs, while the stress distributions were unchanged or worsened under other circumstances. CR was the optimal material for partial restorations compared to GIC and MTA.

Wear and fracture of curettes due to sharpening and scaling processes.

OBJECTIVES: 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. METHODS: 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. RESULTS: 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 for >50% of the total wear. CONCLUSIONS: 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.

Efficacy of (-)-epigallocatechin gallate delivered by a new-type scaler tip during scaling and root planing on chronic periodontitis: a split-mouth, randomized clinical trial.

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 < 0.05). Meanwhile, the mean relative abundance of Tannerella forsythia was significantly lower in the combined treatment group (p < 0.05). 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 .

Three-dimensional quantitative measurement of buccal augmented tissue with modified coronally advanced tunnel technique and de-epithelialized gingival graft: a prospective case series.

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.

MFN2 silencing promotes neural differentiation of embryonic stem cells via the Akt signaling pathway.

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.

Measuring the subgingival microbiota in periodontitis patients: Comparison of the surface layer and the underlying layers.

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.

Correlation study on mtDNA polymorphisms as potential risk factors in aggressive periodontitis by NGS.

OBJECTIVES: Using next-generation sequencing (NGS) to determine whether aggressive periodontitis is associated with specific mitochondrial polymorphisms. MATERIALS AND METHODS: A total of 165 unrelated Han Chinese were enrolled in the study. We analyzed the mitochondrial DNA (mtDNA) in 97 patients with aggressive periodontitis and 68 healthy controls by NGS. The mitochondrial DNA was L-PCR-amplified and subsequently sequenced by an Illumina Genome Analyzer (NGS). Chi-square tests were used to assess the differences between the two groups. In cases of significant difference, multivariate logistic regression models were further used to analyze the association between mtDNA polymorphisms and aggressive periodontitis. RESULTS: Significant association was observed between aggressive periodontitis and eight mitochondrial polymorphisms: "8860G-10400C" (OR = 2.828, p = .002), "8701A" (OR = 2.308, p = .005), "12705C-10398A" (OR = 2.683, p = .002), "9540C" (OR = 3.838, p = .001) and "10873T-15043G" (OR = 4.375, p = .001). CONCLUSIONS: The pathogenesis of aggressive periodontitis is complicated, and its heredity is not well characterized. Our study was the first to use next-generation sequencing and found that 8860G-10400C, 8701A, 12705C-10398A, 9540C, and 10873T-15043G are associated with aggressive periodontitis in the Han Chinese population.

Shift in the subgingival microbiome following scaling and root planing in generalized aggressive periodontitis.

AIM: To investigate the shift in the subgingival microbiota under scaling and root planing (SRP) in patients with generalized aggressive periodontitis (GAgP). MATERIALS AND METHODS: After undergoing supragingival scaling, 12 individuals with GAgP were enrolled in this longitudinal study. Full-mouth SRP was accomplished in 3 weeks and re-evaluated 6 weeks later. Pooled subgingival samples (posterior-mesial, posterior-buccal, anterior-mesial, and anterior-buccal) were obtained from each patient before SRP (pre-treatment group) and at the time of re-evaluation (post-treatment group). 16S rRNA PCR products were generated and sequenced after DNA isolation. RESULTS: Under SRP, the diversity of the subgingival community was consistent, whereas genus-level biomarkers transformed from Porphyromonas, Treponema, and Fretibacterium to Actinomyces, Streptococcus, and Haemophilus. In a network analysis, pathogen-related and non-pathogen-related components were identified in both the pre- and post-treatment groups; the pathogen component was dramatically augmented, while the non-pathogen component shrank after treatment. Hubs were also distributed in both components pre-treatment and were confined to the pathogen component post-treatment. CONCLUSIONS: Scaling and root planing decreased periodontal pathogens in the subgingival microbiota of patients with GAgP. However, the shift in the microbiota composition was characterized by the expansion of pathogen-related components and the contraction of non-pathogen-related components 6 weeks after SRP. Clinicaltrials.gov #NCT03090282.

The Effect of Ultrasound, Oxygen and Sunlight on the Stability of (-)-Epigallocatechin Gallate.

(-)-Epigallocatechin gallate (EGCG), is the main catechin found in green tea, and has several beneficial effects. This study investigated the stability of EGCG aqueous solution under different stored and ultrasonic conditions to determine whether it can be used with an ultrasonic dental scaler to treat periodontal infection. Four concentrations (0.05, 0.1, 0.15, 2 mg/mL) of EGCG aqueous solution were prepared and stored under four different conditions (A: Exposed to neither sunlight nor air, B: Exposed to sunlight, but not air, C: Not exposed to sunlight, but air, D: Exposed to sunlight and air) for two days. The degradation rate of EGCG was measured by high performance liquid chromatography (HPLC). On the other hand, an ultrasonic dental scaler was used to atomize the EGCG solution under four different conditions (a: Exposed to neither air nor sunlight, b: Not exposed to air, but sunlight, c: Not exposed to sunlight, but air, d: Exposed to air and sunlight), the degradation of EGCG was measured by HPLC. We found that the stability of EGCG was concentration-dependent in water at room temperature. Both sunlight and oxygen influenced the stability of EGCG, and oxygen had a more pronounced effect on stability of EGCG than sunlight. The most important conclusion was that the ultrasound may accelerate the degradation of EGCG due to the presence of oxygen and sunlight, but not because of the ultrasonic vibration. Thus, EGCG aqueous solution has the potential to be used through an ultrasonic dental scaler to treat periodontal infection in the future.