OBJECTIVE: To analyze the cement flow in the abutment margin-crown platform switching structure by using the three-dimensional finite element analysis, in order to prove that whether the abutment margin-crown platform switching structure can reduce the inflow depth of cement in the implantation adhesive retention. METHODS: By using ANSYS 19.0 software, two models were created, including the one with regular margin and crown (Model one, the traditional group), and the other one with abutment margin-crown platform switching structure (Model two, the platform switching group). Both abutments of the two models were wrapped by gingiva, and the depth of the abutment margins was 1.5 mm submucosal. Two-way fluid structure coupling calculations were produced in two models by using ANSYS 19.0 software. In the two models, the same amount of cement were put between the inner side of the crowns and the abutments. The process of cementing the crown to the abutment was simulated when the crown was 0.6 mm above the abutment. The crown was falling at a constant speed in the whole process spending 0.1 s. Then we observed the cement flow outside the crowns at the time of 0.025 s, 0.05 s, 0.075 s, 0.1 s, and measured the depth of cement over the margins at the time of 0.1 s. RESULTS: At the time of 0 s, 0.025 s, 0.05 s, the cements in the two models were all above the abutment margins. At the time of 0.075 s, in Model one, the gingiva was squeezed by the cement and became deformed, and then a gap was formed between the gingiva and the abutment into which the cement started to flow. In Model two, because of the narrow neck of the crown, the cement flowed out from the gingival as it was pressed by the upward counterforce from the gingival and the abutment margin. At the time of 0.1 s, in Model one, the cement continued to flow deep inside with the gravity force and pressure, and the depth of the cement over the margin was 1 mm. In Model two, the cement continued to flow out from the gingival at the time of 0.075 s, and the depth of the cement over the margin was 0 mm. CONCLUSION When the abutment was wrapped by the gingiva, the inflow depth of cement in the implantation adhesive retention can be reduced in the abutment margin-crown platform switching structure.
Finite Element Analysis ; Cementation/methods* ; Gingiva ; Crowns ; Dental Abutments ; Dental Cements ; Dental Stress Analysis

Hereditary gingival fibromatosis (HGF) is a rare inherited condition with fibromatoid hyperplasia of the gingival tissue that exhibits great genetic heterogeneity. Five distinct loci related to non-syndromic HGF have been identified; however, only two disease-causing genes, SOS1 and REST, inducing HGF have been identified at two loci, GINGF1 and GINGF5, respectively. Here, based on a family pedigree with 26 members, including nine patients with HGF, we identified double heterozygous pathogenic mutations in the ZNF513 (c.C748T, p.R250W) and KIF3C (c.G1229A, p.R410H) genes within the GINGF3 locus related to HGF. Functional studies demonstrated that the ZNF513 p.R250W and KIF3C p.R410H variants significantly increased the expression of ZNF513 and KIF3C in vitro and in vivo. ZNF513, a transcription factor, binds to KIF3C exon 1 and participates in the positive regulation of KIF3C expression in gingival fibroblasts. Furthermore, a knock-in mouse model confirmed that heterozygous or homozygous mutations within Zfp513 (p.R250W) or Kif3c (p.R412H) alone do not led to clear phenotypes with gingival fibromatosis, whereas the double mutations led to gingival hyperplasia phenotypes. In addition, we found that ZNF513 binds to the SOS1 promoter and plays an important positive role in regulating the expression of SOS1. Moreover, the KIF3C p.R410H mutation could activate the PI3K and KCNQ1 potassium channels. ZNF513 combined with KIF3C regulates gingival fibroblast proliferation, migration, and fibrosis response via the PI3K/AKT/mTOR and Ras/Raf/MEK/ERK pathways. In summary, these results demonstrate ZNF513 + KIF3C as an important genetic combination in HGF manifestation and suggest that ZNF513 mutation may be a major risk factor for HGF.
Animals ; Humans ; Mice ; Fibromatosis, Gingival/pathology* ; Gingiva ; Kinesins/genetics* ; Mutation/genetics* ; Phosphatidylinositol 3-Kinases/genetics*

OBJECTIVES: This study aimed to evaluate the efficacy and long-term stability of tunnel technique (TUN) and coronally advanced flap (CAF) combined with connective tissue graft (CTG) in treating gingival recession. METHODS: Databases including PubMed, Web of Science, Embase, and CNKI were electronically searched to collect randomized controlled trial (RCT) of CAF+CTG compared to TUN+CTG in the treatment of Miller class Ⅰ or Ⅱ gingival recession on September 1, 2022. RESULTS: There were 8 RCTs with 305 patients (454 recession sites) participating. The results of the Meta-analysis revealed that, in terms of mean root coverage (MRC) of main indicators, no significant difference was found between the CAF group and the TUN group in both short- and long-term results, which were [MD: 1.45%, 95%CI (-2.93%, 5.82%), P=0.52] and [MD: -0.70%, 95%CI (-6.41%, 5.00%), P=0.81]. However, the CAF group outperformed the TUN group in the long term [MD: 5.69%, 95%CI (0.87%, 10.50%), P=0.02], and the results of complete root coverage (CRC) analysis were similar to those of MRC. In the short term, the TUN group grew keratinized gingiva significantly faster than the CAF group [MD: -0.38 mm, 95%CI (-0.67 mm, -0.10 mm), P=0.008]. Long-term findings revealed no significant difference between the two groups [MD: -0.26 mm, 95%CI (-0.94 mm, 0.43 mm), P=0.46]. The TUN group's secondary index root coverage esthetic score (RES) was statistically significantly higher than the CAF group's [MD: 0.62, 95%CI (0.28, 0.96), P=0.000 3]. Given that there were few results included in the literature and the heterogeneity was too great, no significant difference was observed in the postoperative VAS pain index score [MD: 0.53, 95%CI (-1.96, 3.03), P=0.68]. CONCLUSIONS This study discovered that both CAF+CTG and TUN+CTG can achieve good root coverage in treating gingival recession, with CAF outperforming TUN and both groups achie-ving good long-term stability. After the operation, the TUN group had a higher RES than the CAF group. Given the limitations of this study, more high-quality studies are needed in the future to demonstrate the efficacy of TUN in gingival retraction surgery.
Humans ; Gingival Recession/surgery* ; Treatment Outcome ; Tooth Root ; Esthetics, Dental ; Gingiva/surgery*

Objective: To measure the labial gingival thickness and bone lamella thickness in the maxillary anterior area using digital method, and to analyze the correlation between the two, so as to provide a reference for esthetic restoration and implantation treatment of the upper anterior area. Methods: Fifty-seven patients [23 males, 34 females, (25.8±4.5) years old] who planned to receive posterior dental implant restoration were recruited randomly with the inclusion and exclusion criteria in Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University from May 2020 to October 2020. The 3Shape software was used to perform oral scanning, and cone beam CT (CBCT) was taken for each patient. The image data was fitted and registered by the 3Shape software. The gingival thickness at 2 mm below the gingival margin, bone thickness and gingival thickness at 2 and, 4 mm below the crest of the labial alveolar crest in maxillary central incisors, lateral incisors and canines, were measured. Results: The gingival thickness at 2 mm below the gingival margin of maxillary central incisors, lateral incisors and canines was (1.42±0.21), (1.19±0.17) and (1.23±0.20) mm respectively (F=12.47, P<0.001). The gingival thickness at 2 mm below gingival margin and 4 mm below crest of residual ridge in the male patients were (1.31±0.21) and (0.67±0.22) mm, and those in the female patients were (1.26±0.22) and (0.58±0.19) mm respectively, and there were statistically significant differences in the gingival thickness between the "2 mm below gingival margin" group and the "4 mm below crest of residual ridge" group (t=2.01 and 3.97, P<0.05). There was a positive correlation between gingival thickness and alveolar bone thickness at 2 mm and 4 mm below the crest of residual ridge in maxillary anterior region, and the correlation coefficients (r) were 0.387 and 0.344 respectively (P<0.05). Conclusions: Gingival thickness of maxillary anterior area is related to the tooth position and gender. The gingival thickness of men is greater than that of women.The gingival thickness at 2 and 4 mm below the crest of the alveolar crest is positively correlated with the thickness of the alveolar bone.
Adult ; Alveolar Process/diagnostic imaging* ; Cone-Beam Computed Tomography ; Esthetics, Dental ; Female ; Gingiva/diagnostic imaging* ; Humans ; Incisor/diagnostic imaging* ; Male ; Maxilla/diagnostic imaging* ; Young Adult

Objective: To explore and analyze the correlation between labial gingival morphology and alveolar bone morphology of maxillary anterior teeth in patients with posterior dental implant, so as to provide reference basis for restoration design and esthetic reconstruction of anterior teeth. Methods: Sixty-four patients [24 males, 40 females (25.6±3.3) years old] who planned to receive posterior dental implant restoration were recruited randomly with the inclusion and exclusion criteria in Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University from May 2020 to May 2021. According to the visibility of periodontal probe through gingival margin, the subjects were divided into thin and thick gingival biotypes, including 29 cases of thin biotype and 35 cases of thick biotype. The 3Shape software was used to perform oral scanning, and cone beam CT (CBCT) was taken for each patient. Geomagic and Mimics software were used to measure and record the labial crown width and length, gingival papilla height, gingival angle, bone papilla height and bone margin angle of maxillary anterior teeth. Results: The crown width length ratios of maxillary central incisors, lateral incisors and canines were 0.85±0.08, 0.80±0.08 and 0.86±0.09 (F=10.71, P<0.01). The height of gingival papilla between maxillary central incisors, between central incisors and lateral incisors, between lateral incisors and canines were (3.93±0.86), (3.47±0.84) and (3.38±0.91) mm respectively (F=7.44, P<0.01), and the height of corresponding bone papilla were (3.44±0.88), (3.12±0.75) and (2.72±0.63) mm respectively (F=14.26, P<0.01). The gingival margin angles of maxillary central incisors, lateral incisors and canines were 88.3°±7.7°, 84.7°±8.9° and 81.2°±6.6° (F=13.15, P<0.01), and the bone margin angles were 103.2°±13.1°, 99.5°±11.2° and 110.6°±13.0° (F=13.25, P<0.01). The crown width length ratio (0.81±0.08), gingival margin angle (82.2°±7.4°) and bone margin angle (99.4°±12.9°) of thin gingival subjects were significantly lower than those of thick gingival subjects (0.85±0.09, 86.5°±8.6°, 108.5°±11.4°) (t=-2.79, 3.63, 5.20, P<0.01). The height of gingival papilla [(3.93±0.81) mm] and bone papilla [(3.43±0.80) mm] in thin gingival subjects were significantly lower than those in thick gingival subjects [(3.34±0.84) and (2.85±0.71) mm, respectively] (t=-4.89, -5.36, P<0.01). The height of labial gingival papilla of upper anterior teeth was positively correlated with that of bone papilla in all patients (r=0.66, P<0.01); the ratio of crown width to length of upper anterior teeth was positively correlated with the angle of bone margin (r=0.42, P<0.01); the height of anterior gingival papilla was negatively correlated with the angle of bone margin (r=-0.58, P<0.01), and the height of bone papilla was negatively correlated with the angle of bone margin (r=-0.82, P<0.01). Conclusions: The crown shape, gingival shape and alveolar bone shape of maxillary anterior teeth were different in different tooth positions. Patients with different periodontal phenotypes had different crown width length ratio, gingival papilla height, bone papilla height, gingival margin angle, and bone margin angle.
Adult ; Cone-Beam Computed Tomography ; Dental Implants ; Esthetics, Dental ; Female ; Gingiva/anatomy & histology* ; Humans ; Male ; Maxilla/diagnostic imaging* ; Tooth Crown ; Young Adult

Objective: To provide reference for clinical application of liquid plasmatrix, and to investigate the optimal centrifugation time of liquid plasmatrix prepared by horizontal centrifugation for soft tissue regeneration from the aspects of mechanical properties, biological properties, and the effect of promoting soft tissue regeneration. Methods: Venous blood was collected from 6 healthy volunteers [3 males and 3 females, aged (26±2) years, with informed consent] who volunteered to donate blood at School of Stomatology, Wuhan University from September to November 2021. The collected venous blood was centrifuged at 500 ×g for 3, 5, 8 and 12 min to obtain liquid plasmatrix. The volume, weight, solidification time, and mechanical properties of liquid plasmatrix prepared at different centrifugation time were measured and recorded (the sample size at each time point was 3). The microstructure of different groups of liquid plasmatrix clot was observed by scanning electron microscope (SEM). The rheological properties of each group of liquid plasmatrix clot were measured by rheological test. The number and concentration of cells in the whole blood group and in each liquid plasmatrix group were measured using complete blood count test. The distribution of cells in the liquid plasmatrix clots was observed by hematoxylin-eosin staining. The effect of control group (Dulbecco's modified Eagle's medium containing 20% fetal bovine serum) and liquid plasmatrix clot exudates in 3, 5, 8, 12 min group (the sample size at each time point was 3) on gingival fibroblast migration was detected by cell migration method. Finally, the effects of control group and liquid plasmatrix clot exudates on the morphology of gingival fibroblasts were observed by fluorescence microscope. Results: The volume of liquid plasmatrix in 3, 5, 8 and 12 min group were approximately (2.47±0.12), (2.67±0.12), (3.53±0.12) and (3.73±0.12) ml, respectively. The weight of liquid plasmatrix in 3, 5, 8 and 12 min group were approximately (0.35±0.01), (0.46±0.02), (0.88±0.06) and (1.03±0.01) g, respectively. The maximum tensile force of liquid plasmatrix clots in 3, 5, 8 and 12 min group were (0.55±0.03), (0.56±0.03), (1.31±0.05) and (1.38±0.02) N, respectively. SEM results showed that the fibers inside the liquid plasmatrix clot became denser with increased centrifugation time. Compared with other groups, the concentrations of leukocytes, neutrophils, monocytes and lymphocytes in 8 min group were the highest, and the distribution of cell was more even. Compared with other groups, the efficiency of stimulating gingival fibroblast migration in 8 min group was the best (1.60±0.01). Fluorescence staining test showed that the liquid plasmatrix clot exudates could make gingival fibroblasts more stretched compared with control group. Conclusions: The present study shows that liquid plasmatrix prepared by centrifugation with 500 ×g centrifugal force for 8 min has higher concentration of viable cells and the ability to promote the migration of gingival fibroblasts.
Cell Movement ; Centrifugation/methods* ; Female ; Fibroblasts ; Gingiva ; Humans ; Male ; Wound Healing

Humans ; Gingival Recession/surgery* ; Gingivoplasty/methods* ; Connective Tissue/transplantation* ; Treatment Outcome ; Gingiva/transplantation* ; Tooth Root

OBJECTIVES: This study was performed to clarify the effects of sitagliptin on METHODS: Healthy gingival samples were collected from the donors. HGFs were isolated with enzymic digestion method and identified. The effects of LPS and sitagliptin on cell viability were detected by cell-counting kit-8 (CCK8). The mRNA levels of inflammatory cytokines, namely, interleukin (IL)-6, IL-8, C-C motif ligand 2 (CCL2), and superoxide dismutase 2 (SOD2), were evaluated by quantity real-time polymerase chain reaction (qRT-PCR) and enzyme-linked immune sorbent assay (ELISA) was used to measure the secretion protein levels of IL-6, IL-8, and CCL2. Western blot analysis was used to further investigate the activation of nuclear factor (NF)-κB signaling pathway. The effect of NF-κB pathway inhibitor BAY11-7082 on LPS-induced HGF inflammatory cytokines at the gene level was verified by qRT-PCR. RESULTS: Low concentrations of sitagliptin (0.1, 0.25, and 0.5 µmol·L CONCLUSIONS Sitagliptin could significantly inhibit LPS-induced HGF inflammatory response by blocking the NF-κB signaling pathway activation.
Fibroblasts ; Gingiva/metabolism* ; Humans ; Lipopolysaccharides ; NF-kappa B/metabolism* ; Signal Transduction ; Sitagliptin Phosphate

OBJECTIVES: The proliferation, migration capacity, and expression of activation-related proteins of NHGFs+Cal27-exo were determined by coculturing Cal27 exosome (Cal27-exo) with normal human gingival fibroblasts (NHGFs) to explore the effects of Cal27-exo on the activation and biological behavior of NHGFs. METHODS: Cal27-exo was extracted using supercentrifugation, and exosomes were identified using Western blot, transmission electron microscopy (TEM), and particle size detection. Cal27-exo was cocultured with NHGFs to detect the uptake of Cal27-exo by NHGFs, and the proliferation and migration capacity of NHGFs+Cal27-exo were detected using CCK8 and wound healing tests, respectively. The expression levels of NHGF activation-related proteins, i.e., matrix metalloproteinase-9 (MMP-9), fibroblast-activating protein (FAP), alpha smooth muscle actin (αSMA), and transforming growth factor-β (TGF-β), were detected using real-time quantitative polymerase chain reaction (qRT-PCR). RESULTS: Cal27-exo was extracted u-sing supercentrifugation, and Western blot showed the positive expression levels of Alix and CD63. TEM showed that Cal27-exo had a circular double-layer vesicle. The particle size was between 30 and 150 nm. Cal27-exo labeled with PKH67 entered NHGFs after the coculture method. The wound healing test showed that the migration capacity of NHGFs+Cal27-exo was stronger after the scratch compared with that of NHGFs. CCK8 results showed that the proliferation activity of NHGFs+Cal27-exo was enhanced. qRT-PCR results showed that the MMP-9 levels of NHGFs+Cal27-exo were upregulated, whereas the TGF-β and αSMA mRNA levels of NHGFs+Cal27-exo were downregulated ( CONCLUSIONS The proliferation and migration ability of NHGFs+Cal27-exo are enhanced, and the mRNA expression of related proteins is changed. Cal27-exo can activate NHGFs, which suggests that Cal27-exo has potential significance in tumor invasion and metastasis.
Cell Proliferation ; Exosomes ; Fibroblasts ; Gingiva ; Humans ; Matrix Metalloproteinase 9

ABSTRACT Green tea (Camellia sinensis) has high level of flavonoids which are proven to have anti-inflammatory activity. Effect of flavonoids can be enhanced by nano-chitosan capsulation as drug carrier. Chitosan is polysaccharide derived from crustacean shells that mostly used as matrix of various drugs and plant extracts. The aim of this study was to determine the effectivity of flavonoids in green tea extract in nanochitosan capsulation towards the number of fibroblasts on proliferative phase of gingival wound healing process. Green tea was extracted, encapsulated with nano-chitosan and then made into gel. Gingiva labial of 24 male white 3-month-old Wistar rats were wounded by punch biopsy (2 mm diameter), then were treated two times a day, and were divided randomly into four groups of topical gel applications: green tea extract gel encapsulated nano-chitosan, green tea extract gel, base gel as negative control, and NSAIDs gel as positive control, starting at 0 day until 7th day. At 5th and 7th day, three rats from each group were decapitated and the mandibular gingiva was taken in order to make histology slides with hematoxylin eosin staining. Under microscope, the number of fibroblasts were examined. The data were analysed using ANOVA test with 95% confidence level. The results showed that the number of fibroblasts on proliferative phase was significantly higher than control negative (p < 0.05) and has no significant differences (p > 0.05) with control positive. In conclusion, topical application of green tea extract gel encapsulated nano-chitosan was effective to accelerate rats gingival wound healing process by increasing the fibroblasts.
Camellia sinensis ; Chitosan ; Gingiva--injuries ; Wound Healing ; Rats, Wistar