Nickel ion release and surface analyses on instrument fragments fractured beyond the apex: a laboratory investigation.

Background: To analyse the changes in surface and nickel ion release characteristics of fractured root canal shaping instruments in a simulated body fluid environment.

Methods: A total of 54 new instruments were studied. The instrument groups consisted of five different NiTi alloys and a stainless-steel alloy.

Evaluation of removal efficiency of capping materials used in pulp revascularization in vitro.

Background: This study aimed to evaluate the removal efficiency of different capping materials used in pulp revascularization (PR) in a failure scenario.

Methods: The apices of freshly extracted 30 maxillary incisors were cut to mimic the immature teeth; then, root canals were shaped up to #6 Peeso reamers. The regeneration steps of the American Association of Endodontists (AAE) were followed to simulate PR treatment in vitro.

Detection of tooth numbering, frenulum attachment, gingival overgrowth, and gingival inflammation signs on dental photographs using convolutional neural network algorithms: a retrospective study.

Objectives: This study aimed to develop an artificial intelligence (AI) model that can determine automatic tooth numbering, frenulum attachments, gingival overgrowth areas, and gingival inflammation signs on intraoral photographs and to evaluate the performance of this model.

Method And Materials: A total of 654 intraoral photographs were used in the study (n = 654). All photographs were reviewed by three periodontists, and all teeth, frenulum attachment, gingival overgrowth areas, and gingival inflammation signs on photographs were labeled using the segmentation method in a web-based labeling software.

Severity and progression rate of periodontitis are associated with an increased risk of hypertension of patients attending a university clinic.

Background: Although periodontitis is associated with increased risk of hypertension, studies based on new periodontal disease classification is limited. We investigated whether periodontitis severity and progression rate are linked with self-reports on doctor-diagnosed hypertension in a large cohort of patients attending the periodontology clinic at the faculty of dentistry.

Methods: Archived patient files, including radiographic image records and results from full-mouth clinical periodontal examination were screened for inclusion.

The impact of smoking on periodontal status and dental caries.

Introduction: Investigations to explore the relationship between smoking and its oral manifestations are important to clinicians. Among these oral manifestations, periodontal diseases and dental caries have still a controversial association. This study aims to analyze the effect of smoking on periodontal disease and caries and their relevance to each other.

The impact of smoking on oral health and patient assessment of tobacco cessation support from Turkish dentists.

Introduction: Dentists are in a critical position to help patients quit smoking. This study analyses the effectiveness of Turkish dentists in smoking cessation as part of routine patient care.

Methods: An in-person cross-sectional survey on previous dental visit experiences was completed by 226 patients recruited from the Department of Periodontology, Eskisehir Osmangazi University, Turkey, from March 2019 to September 2019.

Electronic cigarette liquid substances propylene glycol and vegetable glycerin induce an inflammatory response in gingival epithelial cells.

Information on the effects of propylene glycol (PG) and vegetable glycerin (VG) and on cytotoxicity and subsequent activation of the biological mediators is limited in periodontal diseases. This study analyzes the effect of unflavored PG/VG alone or in combination with nicotine on gingival epithelial cells. The cells were exposed to different PG/VG (± nicotine) concentrations for 24 h and cytotoxicity was evaluated by calorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromid assay.

Biofilm Reduces Gingival Epithelial Cell Keratin Expression in an Organotypic Gingival Tissue Culture Model.

Epithelial cells express keratins, which are essential for the structural integrity and mechanical strength of the cells. In the junctional epithelium (JE) of the tooth, keratins such as K16, K18, and K19, are expressed, which is typical for non-differentiated and rapidly dividing cells. The expression of K17, K4, and K13 keratins can be induced by injury, bacterial irritation, smoking, and inflammation.

The effect of smoking on the marginal bone loss around implant-supported prostheses.

Introduction: Implantology has led to several changes in the planning process involved in the application of dental prostheses to diminish bone level changes along the margins of dental implants. However, the relationship between smoking and marginal bone loss around dental implants, supporting both fixed and removable prostheses has not been investigated. We hypothesize that the design of different prostheses alter the effects of smoking, which consequently affects the amount of supporting alveolar bone.

Effects of IL-13 on TGF-β and MMP-1 in periodontitis.

Periodontitis is an inflammatory disease of the supporting tissues of the teeth. Interleukin (IL)-13 is a multifunctional T-helper type2 (Th2) cytokine that can diminish inflammatory responses. I investigated using ELISA the effects of IL-13 on transforming growth factor-beta (TGF-β) and matrix metalloproteinase-1 (MMP-1).

A novel intrinsically disordered outer membrane lipoprotein of Aggregatibacter actinomycetemcomitans binds various cytokines and plays a role in biofilm response to interleukin-1β and interleukin-8.

Intrinsically disordered proteins (IDPs) do not have a well-defined and stable 3-dimensional fold. Some IDPs can function as either transient or permanent binders of other proteins and may interact with an array of ligands by adopting different conformations. A novel outer membrane lipoprotein, bacterial interleukin receptor I (BilRI) of the opportunistic oral pathogen Aggregatibacter actinomycetemcomitans binds a key gatekeeper proinflammatory cytokine interleukin (IL)-1β.

The function of TLR4 in interferon gamma or interleukin-13 exposed and lipopolysaccharide stimulated gingival epithelial cell cultures.

Gingival epithelial cells are part of the first line of host defense against infection. Toll-like receptors (TLRs) serve important immune and nonimmune functions. We investigated how interferon gamma (INF-γ) and interleukin 13 (IL-13) are involved in the TLR4 ligand-induced regulation of interleukin-8 (IL-8) effects on gingival epithelial cells.

Expression of cathepsin K in periodontitis and in gingival fibroblasts.

Objective: To study non-osteoclastic sources of cathepsin K in periodontitis.

Materials And Methods: Tissue samples were obtained from 10 otherwise healthy periodontitis pati-ents during routine periodontal flap operations and 10 systemically and periodontally healthy individuals who underwent extraction operations for retained third molars. Methods used were immunohistochemistry, image analysis, immunofluorescence double-staining, gingival fibroblast culture, tumour necrosis factor-α (TNF-α) stimulation and Western blotting.

Interleukin-1 superfamily member, interleukin-33, in periodontal diseases.

Interleukin (IL) -33 is a nuclear protein that is released from damaged cells and acts as an alarmin. We investigated the expression of IL-33 in human gingival fibroblasts after stimulation by tumor necrosis factor alpha (TNF-α). Human periodontal tissue samples were collected and fixed in phosphate-buffered 4% formalin in saline and processed to paraffin blocks.

Toll-like receptors 2 and 5 in human gingival epithelial cells co-operate with T-cell cytokine interleukin-17.

Background/aim: Periodontitis begins as the result of perturbation of the gingival epithelial cells caused by subgingival bacteria interacting with the epithelial cells via pattern recognition receptors. Toll-like receptors (TLRs) have been shown to play an important role in the recognition of periodontal pathogens so we have studied the interaction of TLR ligands with TLR2 and TLR5 for cytokine production in the cultures of gingival epithelial cells.

Methods: Immunohistochemistry was used for the localization of TLR2 and TLR5 in tissue specimens.

Chronic sinusitis associated with the use of unrecognized bone substitute: a case report.

Bone grafts are used for bone augmentation to ensure optimal implant placement. However, this procedure may sometimes cause sinusitis. The case of a 44-year-old woman with the diagnosis of recurrent and chronic sinusitis of her right maxillary sinus with a history of dental implant surgery is presented.

Immunohistochemical localization of Toll-like receptors 1-10 in periodontitis.

Background/aim: In periodontitis, bacteria and pathogen-associated molecular patterns are sensed by Toll-like receptors (TLRs), which initiate intracellular signaling cascades that may lead to host inflammation. In this study, the expression and distribution of TLRs (TLR-1 to TLR-10) were immunohistochemically detected in gingival epithelium and connective tissue.

Methods: Immunohistochemistry was used for the localization of TLRs in gingival tissue samples from 10 patients with chronic periodontitis and 10 healthy controls; these samples were obtained during routine periodontal flap operations and during extraction operations performed for retained wisdom teeth, respectively.

Type IV collagen alpha-chain composition in synovial lining from trauma patients and patients with rheumatoid arthritis.

Objective: Normal synovial lining is composed of macrophage-like type A and fibroblast-like type B lining cells. This sheet-like structure lacks a basement membrane, but its intercellular substance contains some basement membrane components, including type IV collagen. We undertook this study to determine the alpha-chain composition of type IV collagen in normal and arthritic synovial lining, using monoclonal alpha-chain antibodies.

A possible CD1a Langerhans cell-mast cell interaction in chronic hyperplastic candidosis.

Aims: T lymphocyte-antigen-presenting cell (APC) interaction plays a central role in T lymphocyte activation and APC maturation. We therefore studied the CD1a-positive Langerhans cells with respect to receptor activator of nuclear factor kappa B ligand (RANKL)-positive cells in chronic hyperplastic candidosis (CHC).

Materials And Methods: Tissue sections of CHC were compared with leukoplakia and healthy oral mucosa using RANKL and CD1a monoclonal antibodies in an avidin-biotin peroxidase complex protocol.

MMPs, IL-1, and TNF are regulated by IL-17 in periodontitis.

Periodontitis is characterized by periodontal tissue destruction. Since interleukin-17 (IL-17) has been reported to up-regulate IL-1beta and tumor necrosis factor-alpha (TNF-alpha), it was hypothesized that it is increased in periodontitis and up-regulates these cytokines and tissue-destructive matrix metalloproteinases (MMP) in local migrant and resident cells. Immunocytochemistry disclosed elevated IL-1beta, TNF-alpha, and IL-17 levels in periodontitis.

Effects of two multi-step self-etch primer/adhesives on apoptosis in human gingival fibroblasts in vitro.

Various in vitro studies have shown induction of apoptosis by monomers incorporated to dental restorative materials and adhesive resins, while information regarding the effect of monomer combinations as commercially available products on apoptosis is limited. The aim of this study was to investigate the effects of two multi-step self-etch primer/adhesive systems on apoptosis of cultured primary human gingival fibroblasts. Cells were treated up to 48 h with Clearfil SE Bond (Kuraray, Japan) and FL Bond (Shofu, Japan) at 1:1000 v:v ratio to determine cell proliferation, using 0.

Collagenases in gingival crevicular fluid in type 1 diabetes mellitus.

Background: Studies have demonstrated that high levels of collagenase activity in gingival crevicular fluid (GCF) are associated with degradation of periodontal tissues in progressive periodontitis compared to periodontally healthy tissues. Because the activation of collagenases is an important issue in periodontitis, we have studied the activation of collagenase in gingival crevicular fluid samples of diabetic patients.

Methods: Collagenase activity was studied in human gingival crevicular fluids.

Gingival tissue and crevicular fluid co-operation in adult periodontitis.

Activated matrix metalloproteinase-3 (MMP-3) can contribute to periodontal ligament destruction in adult periodontitis. Since MMP-3 has been reported to activate proMMP-8 and -9, it was speculated that gingival tissue fibroblast-derived MMP-3 might, in periodontitis, be responsible for activation of gingival crevicular fluid (GCF) neutrophil-derived proMMP-8 and -9. Immunohistochemistry disclosed MMP-3 in gingival fibroblasts in periodontitis.

Role of TNF-alpha and its receptors in pericoronitis.

The classic stimulus for cellular cytokine production is bacterial lipopolysaccharide (endotoxin). It was therefore hypothesized that tumor necrosis factor-alpha (TNF-alpha) may be responsible for pericoronitis. TNF-alpha and its receptors were detected by immunohistochemical staining in third molar pericoronitis in ten patients and ten healthy control samples.