Effect of light-, chemical-, and dual-cured universal adhesives on the internal adaptation of resin composites to pulpal and gingival internal walls.

PURPOSE: To compare the internal adaptation of restorative systems bonded to mid-coronal and gingival dentin using light-cured, chemical-cured, and dual-cured adhesives, both immediately and after aging. METHODS: 60 molars were selected and received occluso-mesial preparations with dentin gingival margins. Restorations were performed using different restorative systems with light-cured, chemical-cured, and dual-cured adhesives. Internal adaptation was assessed by examining the percentage of continuous margin (%CM) at the pulpal and gingival dentin under a scanning electron microscope at x200 magnification. Half of the teeth were stored in sterile water for 24 hours, while the other half underwent 10,000 thermal cycles. Micro-morphological analysis was conducted on representative samples at x1,000 magnification. RESULTS: The restorative system with light-cured adhesive exhibited significantly lower %CM values at the gingival dentin, particularly after aging. Aging had a negative impact on the %CM values of the pulpal and gingival dentin in restorative systems with light-cured and dual-cured adhesives. Regional dentin variations influenced the %CM values, especially after aging, regardless of the restorative system used. The tested restorative system with chemical-cured adhesive is preferable for achieving improved internal adaptation when bonding to both mid-coronal and gingival dentin, compared to the other tested systems. CLINICAL SIGNIFICANCE: The study highlights the variations in adhesive performance between different regional dentin areas using the tested restorative systems.

Autogenous graft versus collagen matrices for peri-implant soft tissue augmentation. A systematic review and network meta-analysis.

OBJECTIVE: The primary objective of this review is to compare autogenous soft tissue grafts (connective tissue graft - CTG and free gingival graft-FGG) with different type of matrices (acellular dermal matrix-ADM, xenograft collagen matrix-XCM, volume-stable collagen matrix-VCMX) used to increase peri-implant soft tissues. MATERIALS AND METHODS: A search on electronic databases was performed to identify randomized and non-randomized controlled trials (RCTs and CCTs, respectively) with either parallel or split-mouth design, and treating ≥ 10 patients. A network meta-analysis (NMA) was used to compare different matrices. Soft tissue thickness dimensional changes and keratinized width (KMW) changes were the primary outcome measures. The secondary outcomes were to evaluate: a) PROMs; b) volumetric changes; c) surgical operating time; and d) different periodontal measurements. RESULTS: A total of 23 studies were included in the qualitative analysis, and 16 studies (11 RCTs and 5 CCTs) in the quantitative analysis. A total of N = 573 sites were evaluated for NMA. CTG resulted the best material for increasing peri-implant soft tissue thickness, at 180 and 360 days after surgery. The use of an ADM showed good results for buccal thickness increase, primarily in the first three months after surgery. Vestibuloplasty + FGG resulted in the most effective technique for peri-implant KMW augmentation, after 180 days. CONCLUSIONS: While CTG demonstrated better performance in all the comparison and FGG showed to be the best graft to increase keratinized mucosa up to 90 days, ADM and VCMX may be used to increase soft tissue horizontal thickness with lower patients' morbidity. LIMITATIONS: The limits of this NMA are the following: a) limited number of included studies; b) high heterogeneity among them (number of patients, treatment sites, surgical techniques, outcome measures, and follow-ups). CLINICAL RELEVANCE: Many studies compared the efficacy of autogenous and non-autogenous grafts in terms of gingival thickness, volume, and keratinized width increase. However, there is still not clear overall evidence on this topic. This NMA helps clinicians to choose the right material in different peri-implant soft tissue procedures. Recommendations for future studies are mandatory.

Elevated subgingival temperature infers high bacterial pathogen counts in severe periodontitis.

OBJECTIVES: Periodontal inflammation may be assessed by bleeding on probing and subgingival temperature. This pilot study evaluated the intrapatient relationship between subgingival temperature and selected bacterial groups/species in deep periodontal pockets with bleeding on probing. MATERIALS AND METHODS: In each of eight adults, an electronic temperature probe identified three "hot" pockets with elevated subgingival temperature and three "cool" pockets with normal subgingival temperature among premolars/molars with 6‒10 mm probing depths and bleeding on probing. Microbial samples collected separately from the hot and cool periodontal pockets were cultured for selected periodontal pathogens. RESULTS: Hot compared to cool periodontal pockets revealed significantly higher absolute and normalized subgingival temperatures and yielded higher mean proportions of Porphyromonas gingivalis (10.2% for hot vs. 2.5% for cool, p = 0.030) and total red/orange complex periodontal pathogens (48.0% for hot vs. 24.6% for cool, p = 0.012). CONCLUSIONS: Hot versus cool deep periodontal pockets harbored significantly higher levels of major periodontal pathogens. Subgingival temperature measurements may potentially be useful to assess risk of periodontitis progression and the efficacy of periodontal therapy.

Expression of visfatin in gingival crevicular fluid and gingival tissues in different periodontal conditions: a cross-sectional study.

BACKGROUND: Studies have shown that visfatin is an inflammatory factor closely related to periodontitis. We examined the levels of visfatin in gingival crevicular fluid (GCF) and gingival tissues under different periodontal conditions, in order to provide more theoretical basis for exploring the role of visfatin in the pathogenesis of periodontitis. METHODS: We enrolled 87 subjects, with 43 in the chronic periodontitis (CP) group, 21 in the chronic gingivitis (CG) group, and 23 in the periodontal health (PH) group. Periodontal indexes (PD, AL, PLI, and BI) were recorded. GCF samples were collected for visfatin quantification, and gingival tissues were assessed via immunohistochemical staining. RESULTS: Visfatin levels in GCF decreased sequentially from CP to CG and PH groups, with statistically significant differences (P < 0.05). The CP group exhibited the highest visfatin levels, while the PH group had the lowest. Gingival tissues showed a similar trend, with significant differences between groups (P < 0.001). Periodontal indexes were positively correlated with visfatin levels in both GCF and gingival tissues (P < 0.001). A strong positive correlation was observed between visfatin levels in GCF and gingival tissues (rs = 0.772, P < 0.001). CONCLUSION: Greater periodontal destruction corresponded to higher visfatin levels in GCF and gingival tissues, indicating their potential collaboration in damaging periodontal tissues. Visfatin emerges as a promising biomarker for periodontitis and may play a role in its pathogenesis.

A Novel "Microscrew With Tie-Down Sutures" Technique for FGG Anchorage: A Case Report.

The most challenging and time-consuming step in the free gingival graft (FGG) for keratinized mucosa augmentation is the compression suture anchoring the FGG to the periosteum. This article proposed a novel "microscrew with tie-down sutures" technique to anchor the FGG to the recipient site without the traditional trans-periosteum suture. This patient's keratinized mucosa width (KMW) around the healing abutments of teeth #29 and #30 was less than 1 mm. After an apically positioned flap (AFP) was prepared, 2 microscrews were placed at the buccal plate of the alveolar ridge bone, which is the coronal margin of the AFP. Then, the sutures winded between the microscrews and the healing abutments to anchor the FGG. In conclusion, the "microscrew with tie-down sutures" technique offers a feasible and straightforward alternative for the trans-periosteum compression suture, mainly when the periosteum is fragile, thin, or injured.

Peri-implant soft tissue volume changes after microsurgical envelope technique with a connective tissue graft. A 5-year retrospective case series.

AIM: The aim of the present retrospective case series was to longitudinally assess soft tissue volume changes on the vestibular aspect of implants in relation to keratinized mucosa thickness (KMT) and width (KMW) after the application of the microsurgical envelope technique combined with a connective tissue graft (CTG). MATERIALS AND METHODS: A total of 12 healthy patients received 12 dental implants placed either in the posterior maxilla or mandible. The study involved the harvesting of 12 CTGs with a minimally invasive single-incision technique, grafted to the vestibular peri-implant soft tissue utilizing the envelope technique, followed by the insertion of 12 screw-retained IPS e.max crowns. RESULTS: The healing process was uneventful across all areas, and all patients were followed up for a period of 5 years. The evaluation of KMT showed the highest decrease in the first 6 weeks after surgery (5.5 ± 0.79 to 4.59 ± 0.62 mm), then dropped slightly to 4 ± 0.85 mm, after which it maintained at 4 ± 0.36 mm until the 2-year time point. Between the second and third years after surgery, a further decrease of 3.59 ± 0.42 mm was recorded for KMT, which then remained constant until the end of the 5-year research period. The observations regarding KMW were slightly different, with the measurements demonstrating the greatest decrease in first 6 weeks (from 2.5 ± 0.42 to 1.5 ± 0.42 mm), which was maintained until the 1-year time point. Between the first and second years after surgery, the KMW increased to 2 ± 0.60 mm and remained level for the next 3 years, at 2 ± 0.85 mm. CONCLUSIONS: The current research demonstrated the advantages of using a combination of a minimally invasively harvested CTG and the microsurgical envelope technique for a duration of 5 years.

Longitudinal analysis of microcirculatory parameters in gingival tissues after tooth extraction in patients with different risk profiles for wound healing disorders - a pilot study.

OBJECTIVES: We aimed to establish a risk profile for intraoral wound healing disorders based on measurements of microcirculation in gingival tissues. MATERIALS AND METHODS: Oxygen saturation (SO2) and blood flow in gingival tissues were measured with tissue spectrometry and laser doppler spectroscopy in 37 patients before/after tooth extractions. Patients were assigned to four groups: anamnestically and periodontally healthy patients (n = 7), anamnestically healthy but suffering from periodontitis (n = 10), anamnestically healthy but smoking and suffering from periodontitis (n = 10) and suffering from diabetes and periodontitis (n = 10). Measurements were performed at three different time points: Baseline measurement (T0), one day post extractionem (p.e.) (T1) and seven days p.e. (T2). RESULTS: Baseline SO2 values were higher in control patients (p = .038). This effect was most evident in comparison to smokers suffering from periodontitis (p = .042), followed by diabetics suffering from periodontitis (p = .09). An opposite trend was seen for blood flow. Patients suffering from periodontitis demonstrated higher blood flow values (p = .012). Five patients, which belonged to the group of smokers suffering from periodontitis, showed clinically a delayed wound healing. CONCLUSION: Differences in SO2 and blood flow of gingival tissue could be detected in different groups of patients with existing periodontitis compared to control patients. CLINICAL RELEVANCE: Lower baseline SO2 values could be a warning signal for possible wound healing disorders after oral surgery.

Evaluation of CD44 antigen in type 2 diabetic patients with periodontitis: An immunohistochemical study.

BACKGROUND: Type 2 diabetes mellitus (DM) is a known systemic risk factor for periodontitis. An increased expression of CD44 has been suggested in type 2 diabetics and periodontitis patients. OBJECTIVES: The present study aimed to assess the expression of CD44 antigen in patients with chronic periodontitis (CP) and type 2 DM in a South Indian urban population. Additionally, the relationships between the expression of CD44 antigen in gingival tissues, periodontal clinical parameters, and the random blood sugar (RBS) and glycated hemoglobin (HbA1c) levels were assessed. MATERIAL AND METHODS: A total of 63 subjects were divided into 3 groups: systemically and periodontally healthy controls (group H); CP patients, otherwise healthy (group CP); and CP patients with type 2 DM (group CP+DM). Periodontal parameters were recorded for all groups, and additionally the RBS and HbA1c levels for group CP+DM. Gingival tissue samples were obtained and subjected to immunohistochemical analysis for CD44. RESULTS: The expression of CD44 was significantly higher in the diseased groups. Epithelial CD44 expression was significantly stronger in group CP+DM as compared to groups CP and H (p < 0.001), whereas connective tissue CD44 expression was similar in groups CP and CP+DM (p = 0.657). Furthermore, an inverse relationship was observed between blood glucose parameters and CD44 expression in the epithelium and connective tissue. CONCLUSIONS: The expression of CD44 increased with the severity of periodontal disease. Additionally, glycemic control in patients with CP and type 2 DM had an impact on CD44 expression. Our findings indicate a possible destructive role of CD44 in the pathogenesis of periodontal diseases in individuals with type 2 DM.

Cytotoxic effect of dental luting cement on human gingival mesenchymal stem cell and evaluation of cytokines and growth factor release - An in vitro study.

AIM: In routine dental care, various dental luting cements are utilized to cement the dental prosthesis. Thus, the aim of the current study was to assess the Cytotoxic effect of three different dental luting cements on human gingival mesenchymal stem cell and evaluation of cytokines and growth factors release. SETTINGS AND DESIGN: Cytotoxicity of glass ionomer cement (GIC), resin modified glass ionomer cement (RMGIC) and resin cement (RC) on the human gingival mesenchymal stem cells (HGMSCs) was evaluated. Amongst the cements tested, least cytotoxic cement was further tested for the release of cytokines and growth factors. MATERIALS AND METHODS: MTT test was used to evaluate the cytotoxicity of the dental luting cements at 1 h, 24 h, and 48 h on HGMSCs. Cytokines such as interleukin (IL) 1α & IL 8 and growth factors such as platelet derived growth factor & transforming growth factor beta release from the least cytotoxic RC was evaluated using flow cytometry analysis. STATISTICAL ANALYSIS USED: The mean absorbance values by MTT assay and cell viability at various time intervals between four groups were compared using a one way analysis of variance test and Tukey's post hoc test. The least cytotoxic RC group and the control group's mean levels of cytokines and growth factors were compared using the Mann-Whitney test. RESULT: As exposure time increased, the dental luting cement examined in this study were cytotoxic. RC was the least cytotoxic, RMGIC was moderate and glass ionomer cement showed the highest cytotoxic effect. Concomitantly, a significant positive biological response of gingival mesenchymal stem cells with the release of ILs when exposed to the RC was observed. CONCLUSION: For a fixed dental prosthesis to be clinically successful over the long term, it is imperative that the biocompatibility of the luting cement be taken into account in order to maintain a healthy periodontium surrounding the restoration.

Is Diet a Determining Factor in the Induction of Gingival Inflammation by Dental Plaque? A Secondary Analysis of Clinical Studies.

The aim was to determine the association between plaque and gingival inflammation reported by dietary interventions. Data of four clinical studies dealing with changed nutrition and gingival examination were reanalyzed with regard to gingival inflammation (GI), plaque (PI), and bleeding on probing (BOP). Dietary changes basically involved avoiding sugar, white flour and sweetened drinks and focusing on whole foods for 4 weeks. The control groups were to maintain their usual diet. All participants had to reduce their oral hygiene efforts. Linear regression models taking the clustering of the data due to several studies into account were applied. In total, data of 92 participants (control groups: 39, test-groups 53) were reanalyzed. While both groups showed a slight increase in dental plaque, only the test groups showed a significant decrease in inflammatory parameters: GI (mean value difference End-Baseline (Δ): -0.31 (±SD 0.36)) and BOP (Δ: -15.39% (±16.07)), both p < 0.001. In the control groups, there was a constant relation between PI and GI, while the experimental group showed a decreasing relationship in GI/PI (p = 0.016), and even an inverted relationship BOP/PI under a changed diet (p = 0.031). In conclusion, diet seems to be a determining factor how the gingiva reacts towards dental plaque.

Relationship of skin complexion with gingival tissue color and hyperpigmentation. A multi-ethnic comparative study.

BACKGROUND AND OBJECTIVE: The most frequently seen intra-oral soft tissue is the gingiva. Most often, it is seen as coral-pink tissue that surrounds the neck of the teeth. Gingiva that encircles the tooth necks and covers the alveolar processes of the jaws is an intra-oral tissue that exhibits biomimetic features. The wide range of colors of the gingiva depends on the configuration of gingival vascularity, the degree of epithelial cornification, level of melanogenesis, and the depth of epithelialization. However, the color of the gingiva varies depending on the degree of melanin pigmentation. The current study aimed to identify the different distribution patterns of gingival color and determine the correlation between skin color, gender, and geographical area of origin. MATERIALS AND METHODS: A total of 839 subjects were involved in the study where the gingival color and skin tone were measured using the Dummett-Gupta Oral pigmentation Index (DOPI) combined with VITA VMK MASTER and skin shade method developed by Revlon (USA) and L'Oreal (France) for makeup foundation shades. One investigator was calibrated for the examination of the colors after being tested for normal color vision and color aptitude using the line test. RESULTS: A significant association was found between skin color and gingival pigmentation (χ2 value (6) = 114.48; P = 0.001). It was also found that females (67.1%) significantly had darker gingiva than males (58.3%). The study statistics display that location of the individual was also statistically associated with melanin pigmentation of the gingiva (χ2 value (57) = 559.33; P = 0.001). CONCLUSION: The study concluded that gender, skin color, and individual location are significantly associated with gingival melanin pigmentation.

Clinical efficacy of intraoral ultrasonography versus transgingival probing for measurement of gingival thickness in different gingival biotypes: a clinical trial.

BACKGROUND: Transgingival probing is conventionally used for gingival thickness (GT) measurement. However, invasiveness is a major drawback of transgingival probing. Thus, researchers have been in search of alternative methods for measurement of GT. This study compared the clinical efficacy of intraoral ultrasonography and transgingival probing for measurement of GT in different biotypes. MATERIALS AND METHODS: This clinical trial was conducted on 34 patients requiring crown lengthening surgery. GT was measured at 40 points with 2- and 4-mm distances from the free gingival margin (FGM) of anterior and premolar teeth of both jaws in each patient by an intraoral ultrasound probe. For measurement of GT by the transgingival probing method, infiltration anesthesia was induced, and a #25 finger spreader (25 mm) was vertically inserted into the soft tissue until contacting bone. The inserted length was measured by a digital caliper with 0.01 mm accuracy. All measurements were made by an operator with high reliability under the supervision of a radiologist. Data were analyzed by t-test, Power and Effect Size formula, and intraclass correlation coefficient (ICC). RESULTS: The two methods were significantly different in measurement of GT in both thick and thin biotypes at 2- and 4-mm distances (P < 0.001). The two methods had a significant difference in both the mandible (P < 0.001) and maxilla (P < 0.001) and in both the anterior (P < 0.003) and premolar (P < 0.003) regions. Although the difference was statistically significant in t-tests, the power and effect formula proved it to be clinically insignificant. Also, the ICC of the two methods revealed excellent agreement. CONCLUSION: The results showed optimal agreement of ultrasound and transgingival probing for measurement of GT. TRIAL REGISTRATION: The study was approved by the ethics committee of Shahid Beheshti University of Medical Sciences on 2021-12-28 (IR.SBMU.DRC.REC.1400.138) and registered in the Iranian Registry of Clinical Trials on 2022-03-14 (IRCT20211229053566N1).

Characterization of oral microbiota in 6-8-month-old small breed dogs.

BACKGROUND: Periodontitis is the most common oral disease in dogs, and its progression and severity are influenced by risk factors, such as age and body size. Recent studies have assessed the canine oral microbiota in relation to different stages of periodontitis and niches within the oral cavity. However, knowledge of the bacterial composition at different ages and body sizes, especially in puppies, is limited. This study aimed to characterize the oral microbiota in the healthy gingiva of small breed puppies using next-generation sequencing. Additionally, we assessed the impact of dental care practices and the presence of retained deciduous teeth on the oral microbiota. RESULTS: In this study, plaque samples were collected from the gingival margin of 20 small breed puppies (age, 6.9 ± 0.6 months). The plaque samples were subjected to next-generation sequencing targeting the V3-V4 region of the 16 S rRNA. The microbiota of the plaque samples was composed mostly of gram-negative bacteria, primarily Proteobacteria (54.12%), Bacteroidetes (28.79%), and Fusobacteria (5.11%). Moraxella sp. COT-017, Capnocytophaga cynodegmi COT-254, and Bergeyella zoohelcum COT-186 were abundant in the oral cavity of the puppies. In contrast, Neisseria animaloris were not detected. The high abundance of Pasteurellaceae suggests that this genus is characteristic of the oral microbiota in puppies. Dental care practices and the presence of retained deciduous teeth showed no effects on the oral microbiota. CONCLUSIONS: In this study, many bacterial species previously reported to be detected in the normal oral cavity of adult dogs were also detected in 6-8-month-old small breed dogs. On the other hand, some bacterial species were not detected at all, while others were detected in high abundance. These data indicate that the oral microbiota of 6-8-month-old small breed dogs is in the process of maturating in to the adult microbiota and may also have characteristics of the small dog oral microbiota.

Assessment of the correlation between supracrestal gingival tissue dimensions and other periodontal phenotypes components via the digital registration method: a cross­sectional study in a Chinese population.

BACKGROUND: Supracrestal gingival tissue dimensions (SGTDs) has been considered to be an essential element of periodontal phenotype (PP) components. This study aimed to explore the relationship between SGTDs and other PP components by digital superposition method that integrated cone beam computed tomography (CBCT) with intraoral scanning. METHODS: This cross-sectional study was conducted at the Stomatology Hospital of Fujian Medical University. Participants were recruited based on the inclusion and exclusion criteria. The data obtained from the digital scanner (TRIOS 3, 3Shape, Denmark) and CBCT images were imported into the TRIOS software (Implant Studio, 3Shape, Denmark) for computing relevant parameters. The significant level was set at 0.05. RESULTS: A total of 83 participants with 498 maxillary anterior teeth were finally included. The mean values of supracrestal gingival height (SGH) and the distance from the cementoenamel junction (CEJ) to the crest of the alveolar ridge (CEJ-ABC) on the buccal site were significantly higher than palatal SGH (SGH-p) and palatal CEJ-ABC (CEJ-ABC-p). Men exhibited taller CEJ-ABC and SGH-p than women. Additionally, tooth type was significantly associated with the SGH, SGH-p and CEJ-ABC-p. Taller SGH was associated with wider crown, smaller papilla height (PH), flatter gingival margin, thicker bone thickness (BT) and gingival thickness (GT) at CEJ, the alveolar bone crest (ABC), and 2 mm apical to the ABC. Smaller SGH-p displayed thicker BT and GT at CEJ, the ABC, and 2 and 4 mm apical to the ABC. Higher CEJ-ABC showed lower interproximal bone height, smaller PH, flatter gingival margin, thinner GT and BT at CEJ, and 2 mm apical to the ABC. Smaller CEJ-ABC-p displayed thicker BT at CEJ and 2 and 4 mm apical to the ABC. On the buccal, thicker GT was correlated with thicker BT at 2 and 4 mm below the ABC. CONCLUSION: SGTDs exhibited a correlation with other PP components, especially crown shape, gingival margin and interdental PH. The relationship between SGTDs and gingival and bone phenotypes depended on the apico-coronal level evaluated. TRIAL REGISTRATION: This study was approved by the Biomedical Research Ethics Committee of Stomatology Hospital of Fujian Medical University (approval no. 2023-24).

The Scalloped Surgical Guide as an Alternative to Flat Bone Reduction Guide in Full-Arch Implant Restoration.

The goal of this clinical report was to present an alternative to traditional flat bone reduction guides, using a custom-designed 3-dimensional (3D)-printed guide according to the future gingival margin of the planned dentition. A 61-year-old woman with concerns regarding her smile appearance was presented. The initial examination revealed excessive gingival show accompanied by excessive overjet. The dentition was in a failing situation. The proposed treatment plan, relying on the sufficient amount of bone and keratinized tissue, consisted of recontouring of the alveolar ridge and gingiva and placement of 6 implants and an FP-1 prosthesis after extraction of all remaining maxillary teeth. Digital smile design was completed, and a fully digitally guided surgery was planned. This consisted of using 3 surgical guides, starting with the fixation pin guide, continuing with the scalloped hard- and soft-tissue reduction guide, and finally the implant placement template. Following the surgery, the patient received a temporary restoration, and on the 4-month follow-up, a new polymethyl meta-acrylate temporary prosthesis was delivered. The patient's 7-month follow-up is presented in the article. The report of this triple-template guided surgery indicated that digital 3D planning is a considerably predictable tool to properly establish and evaluate future occlusal plane, smile line, and lip support. Scalloped guides seem to be an excellent alternative to conventional bone reduction guides since they require less bone removal and improve patient comfort during surgery.

Gingival proteomics reveals the role of TGF beta and YAP/TAZ signaling in Raine syndrome fibrosis.

Raine syndrome (RNS) is a rare autosomal recessive osteosclerotic dysplasia. RNS is caused by loss-of-function disease-causative variants of the FAM20C gene that encodes a kinase that phosphorylates most of the secreted proteins found in the body fluids and extracellular matrix. The most common RNS clinical features are generalized osteosclerosis, facial dysmorphism, intracerebral calcifications and respiratory defects. In non-lethal RNS forms, oral traits include a well-studied hypoplastic amelogenesis imperfecta (AI) and a much less characterized gingival phenotype. We used immunomorphological, biochemical, and siRNA approaches to analyze gingival tissues and primary cultures of gingival fibroblasts of two unrelated, previously reported RNS patients. We showed that fibrosis, pathological gingival calcifications and increased expression of various profibrotic and pro-osteogenic proteins such as POSTN, SPARC and VIM were common findings. Proteomic analysis of differentially expressed proteins demonstrated that proteins involved in extracellular matrix (ECM) regulation and related to the TGFß/SMAD signaling pathway were increased. Functional analyses confirmed the upregulation of TGFß/SMAD signaling and subsequently uncovered the involvement of two closely related transcription cofactors important in fibrogenesis, Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ). Knocking down of FAM20C confirmed the TGFß-YAP/TAZ interplay indicating that a profibrotic loop enabled gingival fibrosis in RNS patients. In summary, our in vivo and in vitro data provide a detailed description of the RNS gingival phenotype. They show that gingival fibrosis and calcifications are associated with, and most likely caused by excessed ECM production and disorganization. They furthermore uncover the contribution of increased TGFß-YAP/TAZ signaling in the pathogenesis of the gingival fibrosis.

Human immunodeficiency virus and oral microbiota: mutual influence on the establishment of a viral gingival reservoir in individuals under antiretroviral therapy.

The role of the oral microbiota in the overall health and in systemic diseases has gained more importance in the recent years, mainly due to the systemic effects that are mediated by the chronic inflammation caused by oral diseases, such as periodontitis, through the microbial communities of the mouth. The chronic infection by the human immunodeficiency virus (HIV) interacts at the tissue level (e.g. gut, genital tract, brain) to create reservoirs; the modulation of the gut microbiota by HIV infection is a good example of these interactions. The purpose of the present review is to assess the state of knowledge on the oral microbiota (microbiome, mycobiome and virome) of HIV-infected patients in comparison to that of HIV-negative individuals and to discuss the reciprocal influence of HIV infection and oral microbiota in patients with periodontitis on the potential establishment of a viral gingival reservoir. The influence of different clinical and biological parameters are reviewed including age, immune and viral status, potent antiretroviral therapies, smoking, infection of the airway and viral coinfections, all factors that can modulate the oral microbiota during HIV infection. The analysis of the literature proposed in this review indicates that the comparisons of the available studies are difficult due to their great heterogeneity. However, some important findings emerge: (i) the oral microbiota is less influenced than that of the gut during HIV infection, although some recurrent changes in the microbiome are identified in many studies; (ii) severe immunosuppression is correlated with altered microbiota and potent antiretroviral therapies correct partially these modifications; (iii) periodontitis constitutes a major factor of dysbiosis, which is exacerbated in HIV-infected patients; its pathogenesis can be described as a reciprocal reinforcement of the two conditions, where the local dysbiosis present in the periodontal pocket leads to inflammation, bacterial translocation and destruction of the supporting tissues, which in turn enhances an inflammatory environment that perpetuates the periodontitis cycle. With the objective of curing viral reservoirs of HIV-infected patients in the future years, it appears important to develop further researches aimed at defining whether the inflamed gingiva can serve of viral reservoir in HIV-infected patients with periodontitis.

Idiopathic gingival fibromatosis and primary analysis of dominant bacteria in subgingival biofilm: a case report.

Idiopathic gingival fibromatosis (IGF), a rare fibroproliferative disease of unknown etiology, affects gingival tissue and has substantial adverse effects on patients. Therefore, the pathogenesis of IGF requires more extensive and in-depth research. In this case, a patient with confirmed IGF underwent initial nonsurgical periodontal therapy and gingivectomy, and the prognosis was good. The patient had no loss of periodontal attachment but had a history of swelling and bleeding of the gingiva prior to fibrous enlargement, which prompted further investigation. We explored the patient's subgingival microbiome and found a high abundance of periodontal pathogens. Gingival tissue biopsy revealed abundant fibrous tissue containing multiple inflammatory cell infiltrates. These results suggest that gingival inflammation secondary to periodontal pathogens can contribute to IGF onset.

Ropinirole suppresses LPS-induced periodontal inflammation by inhibiting the NAT10 in an ac4C-dependent manner.

BACKGROUND: Periodontitis is a chronic osteolytic inflammatory disease, where anti-inflammatory intervention is critical for restricting periodontal damage and regenerating alveolar bone. Ropinirole, a dopamine D2 receptor agonist, has previously shown therapeutic potential for periodontitis but the underlying mechanism is still unclear. METHODS: Human gingival fibroblasts (HGFs) treated with LPS were considered to mimic periodontitis in vitro. The dosage of Ropinirole was selected through the cell viability of HGFs evaluation. The protective effects of Ropinirole on HGFs were evaluated by detecting cell viability, cell apoptosis, and pro-inflammatory factor levels. The molecular docking between NAT10 and Ropinirole was performed. The interaction relationship between NAT10 and KLF6 was verified by ac4C Acetylated RNA Immunoprecipitation followed by qPCR (acRIP-qPCR) and dual-luciferase reporter assay. RESULTS: Ropinirole alleviates LPS-induced damage of HGFs by promoting cell viability, inhibiting cell apoptosis and the levels of IL-1ß, IL-18, and TNF-α. Overexpression of NAT10 weakens the effects of Ropinirole on protecting HGFs. Meanwhile, NAT10-mediated ac4C RNA acetylation promotes KLF6 mRNA stability. Upregulation of KLF6 reversed the effects of NAT10 inhibition on HGFs. CONCLUSIONS: Taken together, Ropinirole protected HGFs through inhibiting the NAT10 ac4C RNA acetylation to decrease the KLF6 mRNA stability from LPS injury. The discovery of this pharmacological and molecular mechanism of Ropinirole further strengthens its therapeutic potential for periodontitis.

PGRN is involved in macrophage M2 polarization regulation through TNFR2 in periodontitis.

BACKGROUND AND OBJECTIVE: Progranulin (PGRN), a multifunctional growth factor, plays indispensable roles in the regulation of cancer, inflammation, metabolic diseases, and neurodegenerative diseases. Nevertheless, its immune regulatory role in periodontitis is insufficiently understood. This study attempts to explore the regulatory effects of PGRN on macrophage polarization in periodontitis microenvironment. METHODS: Immunohistochemical (IHC) and multiplex immunohistochemical (mIHC) stainings were performed to evaluate the expression of macrophage-related markers and PGRN in gingival samples from periodontally healthy subjects and periodontitis subjects. RAW264.7 cells and bone marrow-derived macrophages (BMDMs) were polarized towards M1 or M2 macrophages by the addition of LPS or IL-4, respectively, and were treated with or without PGRN. Real-time fluorescence quantitative PCR (qRT-PCR), immunofluorescence staining (IF), enzyme-linked immunosorbent assay (ELISA), and flow cytometry were used to determine the expressions of M1 and M2 macrophage-related markers. Co-immunoprecipitation was performed to detect the interaction between PGRN and tumor necrosis factor receptor 2 (TNFR2). Neutralizing antibody was used to block TNFR2 to confirm the role of TNFR2 in PGRN-mediated macrophage polarization. RESULTS: The IHC and mIHC staining of human gingival slices showed a significant accumulation of macrophages in the microenvironment of periodontitis, with increased expressions of both M1 and M2 macrophage markers. Meanwhile, PGRN was widely expressed in the gingival tissue of periodontitis and co-expressed mainly with M2 macrophages. In vitro experiments showed that in RAW264.7 cells and BMDMs, M1 markers (CD86, TNF-α, iNOS, and IL-6) substantially decreased and M2 markers (CD206, IL-10, and Arg-1) significantly increased when PGRN was applied to LPS-stimulated macrophages relatively to LPS stimulation alone. Besides, PGRN synergistically promoted IL-4-induced M2 markers expression, such as CD206, IL-10, and Arg1. In addition, the co-immunoprecipitation result showed the direct interaction of PGRN with TNFR2. mIHC staining further revealed the co-localization of PGRN and TNFR2 on M2 macrophages (CD206+). Blocking TNFR2 inhibited the regulation role of PGRN on macrophage M2 polarization. CONCLUSIONS: In summary, PGRN promotes macrophage M2 polarization through binding to TNFR2 in both pro- and anti-inflammatory periodontal microenvironments.