This study aims to histologically and immunohistochemically evaluate the effect recombinant human bone morphogenetic protein (rh-BMP2) injected in gingival tissue has on the acceleration of the epithelial migration from the wound edges and epithelial cell proliferation after implant surgery.
METHODS: The study includes 20 patients who underwent bilateral implant surgeries in the premolar-molar region of the mandible, followed by guided bone regeneration. Each patient received an implant in both locations, but rh-BMP2 was only on the right side. At 9 days from the surgery, a gingival biopsy was performed 3 mm distally to the last implant. In total, 20 samples were collected from the left side (control group #1) and 20 from right (test group #1). This was repeated at a 4-month interval during healing abutment placements. Tissues were processed and stained with hematoxylin-eosin and then immunohistochemically for the expression of Ki-67 and further histological examination.
RESULTS: Complete closure of the epithelium with new cell formation was observed in the 55% test group and 20% control group after 9 days. At 4 months, although 100% samples of all groups had complete epithelial closure, the test group showed that the epithelial cells were more organized and mature due to the increased number of blood vessels. The average number of new epithelial cells was 17.15 ± 7.545 and 16.12 ± 7.683 cells per mm in test group, respectively, at 9 days and 4 months and 10.99 ± 5.660 and 10.95 ± 5.768 in control groups.
CONCLUSIONS: Evident from histological observations, rh-BMP-2 can accelerate the closure of gingival wounds, the healing process of epithelial gingival tissue, and the formation of epithelial cells in patients undergoing dental implant treatment.

UNASSIGNED: Three-dimensional (3D) tissue models bridge the gap between conventional two-dimensional cell cultures and animal models. The aim of this study was to develop an organotypic 3D gingival (OTG) model to provide a tool to investigate bacterial and viral pathogens in periodontitis.
UNASSIGNED: The OTG model composed of gingival fibroblasts (GFs) and telomerase-immortalized gingival keratinocytes (TIGKs) was constructed and applied to study infections by Porphyromonas gingivalis and herpes simplex virus 1 (HSV-1). Immunohistochemical staining, confocal microscopy, qPCR, titration techniques, and colony-forming unit counts were applied to interrogate epithelial markers expression, monitor P. gingivalis and HSV-1 presence, and evaluate the immune response along with the efficiency of antimicrobial drugs.
UNASSIGNED: The OTG model resembled the morphology of the human gingiva. During infection, both pathogens penetrated deep into the tissue and persisted for a few days with P. gingivalis also forming a biofilm on the cell surface. The infection triggered the expression of inflammatory mediators in cells and both pathogens were efficiently eliminated by specific antimicrobials.
UNASSIGNED: Presented OTG model constitutes a simple and convenient tool to study the interaction between bacterial and viral pathogens within the gingival tissue, including penetration, persistence and biofilm formation. It is also suitable to examine the efficiency of antimicrobial drugs.

OBJECTIVE: To investigate the proportional variation of macrophage and T-lymphocytes subpopulations in acute coronary syndrome (ACS) patients, its association with periodontitis (P), and to compare with control individuals.
METHODS: Three groups of subjects participated: one group consisted of 17 ACS patients with P (ACS + P), another group consisted of 22 no ACS + P patients, and a control group consisted of 23 participants with gingivitis (no ACS + G). Macrophage, CD4 + , and CD8 + T-lymphocytes and CD4 + /CD8 + ratio values in gingival tissue were determined histometrically.
RESULTS: Significant differences were found among three groups regarding the mean number of macrophage (no ACS + P > ACS + P > no ACS + G; p < 0.05) and CD8 + T-lymphocytes (no ACS + P > ACS + P > no ACS + G; p < 0.05). Significant variations were observed between the groups both CD4 + T-lymphocytes densities (ACS + P > no ACS + P and ACS + P > no ACS + G; p < 0.05) and CD4 + / CD8 + ratio (no ACS + P < no ACS + G and ACS + P < no ACS + G; p < 0.05).
CONCLUSIONS: The increased number of CD8 + T-lymphocytes in both group ACS + P and group no ACS + P resulted in a reduction of the CD4 + /CD8 + ratio in gingival tissue when compared with no ACS + G group.
CONCLUSIONS: The decrease of CD4 + /CD8 + ratio in gingival tissue reflects periodontitis and may be associated with severe adverse outcomes in people with ACS.

OBJECTIVE: The removal of impacted third molars by surgery may occur with a series of complications, whereas limited information about the postoperative pathogenesis is available. The objective of this study is to identify changes in gene expression after flap surgical removal of impacted third molars and provide potential information to reduce postoperative complications.
METHODS: The gingival tissues of twenty patients with flap surgical removal of impacted third molars and twenty healthy volunteers were collected for gene expression testing. The collected gingival tissues were used RNA sequencing technology and quantitative real-time PCR validation was performed. DEG was mapped to protein databases such as GO and KEGG for functional annotation and, based on annotation information, for mining of differential expression genes in patients with mpacted third molars.
RESULTS: A total of 555 genes were differentially expressed. Among the top up-regulated genes, HLA-DRB4, CCL20, and CXCL8 were strongly associated with immune response and signal transduction. Among the top down-regulated genes, SPRR2B, CLDN17, LCE3D and LCE3E were related to keratinocyte differentiation, IFITM5, and BGLAP were related to bone mineralization, UGT2B17 is associated with susceptibility to osteoporosis. KEGG results showed that the DEGs were related to multiple disease-related pathways.
CONCLUSIONS: This first transcriptome analysis of gingival tissues from patients with surgical removal of impacted third molars provides new insights into postoperative genetic changes. The results may establish a basis for future research on minimizing the incidence of complications after flap-treated third molars.

The aim of this study is to evaluate the effect on the initiation of new blood vessel formation of rh-BMP-2 administration in the human gingival tissue during bone regeneration surgery.
METHODS: The randomized controlled clinical trial included twenty patients with bilateral partial edentulous of the mandibular premolar and molar region. Each patient received one implants on each side. Only one side received a 0.25 µg injection of rhBMP-2 into the gingival flap and grafted material during guided bone regeneration (GBR) for dental implantation. And the other side received GBR without injection. Three samples were collected from each patient as follows: one from the anterior area of the mandible (control group #1) collected at the time of all implant surgeries, and the two other samples during the placement of healing abutments at 4 months of follow-up, from treated side with rh-BMP-2 (test group) and untreated ones (control group #2). A total of 60 gingival samples were collected. Samples were stained with hematoxylin-eosin, and immunohistochemistry was performed with a vascular endothelial growth factor marker. The number of new vessels in each sample was counted.
RESULTS: Statistical analyses showed a significantly higher number of new vessels in the gingival tissue of the test group.
CONCLUSIONS: Rh-BMP-2 injections into the gingival flap significantly improved new blood vessel formation.

The purpose of this study was to determine potential metabolic biomarkers and therapeutic drugs in the gingival tissue of individuals with periodontitis. Liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) were used to analyze the gingival tissue samples from 20 patients with severe periodontitis and 20 healthy controls. Differential metabolites were identified using variable important in projection (VIP) values from the orthogonal partial least squares discrimination analysis (OPLS-DA) model and then verified for significance between groups using a two-tailed Student\'s t test. In total, 65 metabolites were enriched in 33 metabolic pathways, with 40 showing a significant increase and 25 expressing a significant decrease. In addition, it was found that patients with severe periodontitis have abnormalities in metabolic pathways, such as glucose metabolism, purine metabolism, amino acid metabolism, and so on. Furthermore, based on a multidimensional analysis, 12 different metabolites may be the potential biomarkers of severe periodontitis. The experiment\'s raw data have been uploaded to the MetaboLights database, and the project number is MTBLS8357. Moreover, osteogenesis differentiation characteristics were detected in the selected metabolites. The findings may provide a basis for the study of diagnostic biomarkers and therapeutic metabolites in severe periodontitis.

New functional materials for engineering gingival tissue are still in the early stages of development. Materials for such applications must maintain volume and have advantageous mechanical and biological characteristics for tissue regeneration, to be an alternative to autografts, which are the current benchmark of care. In this work, methacrylated gelatin (GelMa) was photocrosslinked with synthetic immunomodulatory methacrylated divinyl urethanes and defined monomers to generate composite scaffolds. Using a factorial design, with the synthetic monomers of a degradable polar/hydrophobic/ionic polyurethane (D-PHI) and GelMa, composite materials were electrospun with polycarbonate urethane (PCNU) and light-cured in-flight. The materials had significantly different relative hydrophilicities, with unique biodegradation profiles associated with specific formulations, thereby providing good guidance to achieving desired mechanical characteristics and scaffold resorption for gingival tissue regeneration. In accelerated esterase/collagenase degradation models, the new materials exhibited an initial rapid weight loss followed by a more gradual rate of degradation. The degradation profile allowed for the early infiltration of human adipose-derived stromal/stem cells, while still enabling the graft\'s structural integrity to be maintained. In conclusion, the materials provide a promising candidate platform for the regeneration of oral soft tissues, addressing the requirement of viable tissue infiltration while maintaining volume and mechanical integrity. STATEMENT OF SIGNIFICANCE: There is a need for the development of more functional and efficacious materials for the treatment of gingival recession. To address significant limitations in current material formulations, we sought to investigate the development of methacrylated gelatin (GelMa) and oligo-urethane/methacrylate monomer composite materials. A factorial design was used to electrospin four new formulations containing four to five monomers. Synthetic immunomodulatory monomers were crosslinked with GelMa and electrospun with a polycarbonate urethane resulting in unique mechanical properties, and resorption rates which align with the original design criteria for gingival tissue engineering. The materials may have applications in tissue engineering and can be readily manufactured. The findings of this work may help better direct the efforts of tissue engineering and material manufacturing.

Diabetes and periodontitis are prevalent diseases that considerably impact global economy and diabetes is a major risk factor of periodontitis. Mitochondrial dynamic alterations are involved in many diseases including diabetes and this study aims to evaluate their relevance with diabetes aggravated periodontitis. Sixty mice are randomly divided into 4 groups: control, periodontitis, diabetes and diabetic periodontitis. Periodontitis severity is evaluated by alveolar bone loss, inflammation and oxidative stress status. Mitochondrial structural and functional defects are evaluated by the mitochondrial fission/fusion events, mitochondrial reactive oxygen species (ROS) accumulation, complex activities and adenosine triphosphate (ATP) production. Advanced glycation end product (AGE) and Porphyromonas gingivalis are closely related to periodontitis occurrence and development. Human gingival fibroblast cells (HGF-1) are used to investigate the AGE role and lipopolysaccharide (LPS) from Porphyromonas gingivalis (P-LPS) in aggravating diabetic periodontitis by mitochondrial dynamic and function alterations. In vivo, diabetic mice with periodontitis show severe bone loss, increased inflammation and oxidative stress accumulation. Among mice with periodontitis, diabetic mice show worse mitochondrial dynamic perturbations than lean mice, along with fusion protein levels inducing more mitochondrial fission in gingival tissue. In vitro, AGEs and P-LPS co-treatment causes severe.

This study aimed to analyse the immunohistochemical profile of inflammatory infiltrates in the gingival tissue of patients undergoing orthodontic treatment in relation to patients’ titanium and/or nickel allergy status. Patients with gingival enlargement received initial periodontal therapy, followed by external gingivectomy in the case of persistent gingival enlargement. The sample included 44 patients (22 had metal allergic sensitisation). Histopathological changes were assessed, and an immunohistochemical analysis was performed on formalin-fixed and paraffin-embedded gingival samples using antibodies against CD1a, CD3, CD4, CD8, CD20, CD68, and CD138. Computer-assisted image analysis was performed to evaluate the positive cell count in the gingival tissue. The gingiva of the sensitised patients was characterised by the absence of multifocal inflammatory infiltrates (p < 0.05), while pronounced exocytosis and band-like inflammatory infiltrates were more frequently observed in sensitised patients. In addition, there was an increase in Langerhans cells and T-helper lymphocytes and a decrease in naïve T-lymphocytes, cytotoxic T-lymphocytes, macrophages, and plasma cells in the sensitised subjects compared to non-sensitised. However, the differences were only statistically significant for macrophages, with a moderate effect size (82.8 vs. 133.9; p = 0.041; r = 0.308). The absence of multifocal inflammation appears to be the most characteristic histopathological feature of the gingiva of sensitised patients. Although their gingiva presented certain characteristics of late hypersensitivity immune reactions the observed changes imply dominant irritative effect e.

Although Vanins are closely related to neutrophil regulation and response to oxidative stress, and play essential roles in inflammatory diseases with clinical significance, their contribution to periodontitis remains to be determined. This research was designed to assess the expression of Vanins in human gingiva, and to define the relationship between Vanins and periodontitis.
Forty-eight patients with periodontitis and forty-two periodontal healthy individuals were enrolled for gingival tissue sample collection. Expression levels of VNN1, VNN2 and VNN3 were evaluated by RT-qPCR and validated in datasets GSE10334 and GSE16134. Western blot and immunohistochemistry identified specific proteins within gingiva. The histopathological changes in gingival sections were investigated using HE staining. Correlations between Vanins and clinical parameters, PD and CAL; between Vanins and inflammation, IL1B; and between Vanins and MPO in periodontitis were investigated by Spearman\'s correlation analysis respectively. Associations between VNN2 and indicators of neutrophil adherence and migration were further validated in two datasets.
Vanins were at higher concentrations in diseased gingival tissues in both RT-qPCR and dataset analysis (p < 0.01). Assessment using western blot and immunohistochemistry presented significant upregulations of VNN1 and VNN2 in periodontitis (p < 0.05). The higher expression levels of Vanins, the larger the observed periodontal parameters PD and CAL (p < 0.05), and IL1B (p < 0.001). Moreover, positive correlations existed between VNN2 and MPO, and between VNN2 and neutrophil-related indicators.
Our study demonstrated upregulation of Vanins in periodontitis and the potential contribution of VNN2 to periodontitis through neutrophils-related pathological processes.