The aim of this study was to evaluate the local changes in the crevicular gingival fluid (CGF) determined by the inflammatory and immune response in periodontitis and gingivitis. The selected patients presented gingivitis (n = 9) and periodontitis: aggressive periodontitis (n = 21) and adult periodontitis (n = 8). The ...

The aim of this study was to determine whether biofilms of Porphyromonas gingivalis could proteolytically degrade the cytokines interleukin (IL)-1beta, IL-6, or IL-1 receptor antagonist (IL-1ra). Biofilms were grown on membrane filters on the surface of Wilkins-Chalgren blood agar. The biofilms were removed from the plates, and solutions containing 2.5 ...

The potential inflammatory and immune markers that might detect periodontal disease severity or activity are examined. The role of inflammatory and immune factors passing from the tissues into the gingival crevicular fluid (GCF) are considered. GCF sampling is a necessary part of all diagnostic tests based on gingival and periodontal ...

Progression factors for periodontal diseases have been suggested by in vitro study of peripheral blood and gingival cells; however, those factors are not established in vivo. This investigation assessed biopsies of three groups of gingival tissues: those adjacent to a 1) < or =3 mm (normal), 2) 4-6 mm, and ...

Periodontal ligament (PDL) cells maintain the attachment of the tooth to alveolar bone. These cells reside at a site in which they are challenged frequently by bacterial products and proinflammatory cytokines, such as interleukin-1beta (IL-1beta), during infections. In our initial studies we observed that IL-1beta down-regulates the osteoblast-like characteristics of ...

Soluble proteins that serve as mediators of cell function and are produced by various cell types, such as structural and inflammatory cells, are collectively called cytokines. Several lines of evidence have revealed that cytokines play important roles not only in tissue homeostasis but also in the pathogenesis of many infectious ...

Periodontal disease and inflammatory dermatoses, such as psoriasis, are characterized by the accumulation of dense inflammatory infiltrates immediately beneath the epithelial cell layer of the gingiva and skin, respectively. Dermatologists are increasingly aware that the epidermal keratinocyte probably contributes to inflammatory disease progression by secreting a number of pro-inflammatory cytokines ...

Chronic inflammation induced by bacteria often leads to host-mediated destruction of tissues adjacent to the sites of microbial insult. The chronic inflammatory process of adult periodontitis results in the destruction of supporting osseous and connective tissues of the teeth. We hypothesized that virulence factors of periodontal pathogens such as lipopolysaccharide ...

This study utilized various mouse strains with documented alterations in immune system components to assess their contribution to modify the virulence of Porphyromonas gingivalis. P. gingivalis W50 was cultivated on blood agar plates, harvested and used to challenge mice by subcutaneous injection on the dorsolateral surface of the back. Soft ...

A previous study used a mouse model to demonstrate protection after challenge with Porphyromonas gingivalis ATCC 33277. In the present study, this same model was used to determine the phenotype of cells recruited into the lesions during the course of the protective immune response after immunization with this periodontal pathogen. ...

Periodontal diseases are inflammatory disorders caused by microorganisms of dental plaque that colonize the gingival sulcus and, subsequently, the periodontal pocket. As in other mucosal infections, the host response to plaque bacteria is characterized by an influx of polymorphonuclear leukocytes (PMNs) to the gingival crevice. Neutrophil migration through the epithelial ...

The fimbriae of Porphyromonas gingivalis plays an important role in the pathogenesis of periodontal disease. A structural subunit of the P. gingivalis fimbriae, fimbrillin, has been shown to promote adherence of the bacteria to host surfaces and also induce an immune response. Biologically active domains of fimbrillin responsible for adherence ...

OBJECTIVES: To study the response to in vitro priming of peripheral neutrophils from patients with periodontitis compared to healthy controls. Peripheral neutrophils from these patients had shown increased production of oxygen radicals after activation with opsonized bacteria and a difference in priming response could suggest an explanation for this hyperreactivity. ...

There are several indications suggesting that interleukin-1beta (IL-1beta) may play an important role in inflammatory periodontal diseases. We hypothesized that periodontal sites would represent a unique combination of both cellular sources of IL-1beta precursor (pro-IL-1beta) and microbial proteases and proposed that Treponema denticola, a suspected periodontal pathogen, would play a ...

Uterine infections are a major reproductive problem in livestock. We conducted two experiments to investigate factors that may modulate uterine responses to infectious bacteria. In Exp. 1, ewes received intrauterine inoculations of either saline or bacteria (75 x 10(7) cfu of Actinomyces pyogenes and 35 x 10(7) cfu of Escherichia ...

This paper aims to review the rôle of free radical-induced tissue damage and antioxidant defence mechanisms in inflammatory diseases that involve pathogenic processes similar to the periodontal diseases. There is a clearly defined and substantial role for free radicals or reactive oxygen species (ROS) in periodontitis, but little research has ...

An in vivo tissue chamber model was developed to enable studies of local cytokine production and cellular events during inflammatory and immune reactions in the pig. Tissue chambers made of sialistic rubber tubing were surgically implanted in the subcutaneous tissue- and samples of tissue chamber fluid (TCF) and inflammatory cells ...

Fusobacterium nucleatum and Actinobacillus actinomycetemcomitans are Gram-negative rod periodontal pathogens. The peritoneal cavity of Institute of Cancer Research (ICR) mice was used as the local infection model. In vivo production of heat-shock proteins (hsp) was studied by injection of 1/10 minimum lethal dose (MLD) of each live bacteria into mice. ...

PMN migration into the gingival sulcus is a tightly regulated process aimed at selectively increasing leukocyte availability at the site of bacterial plaque aggression, i.e. the superficial portion of the junctional epithelium. The evidence reviewed in this paper indicates that, besides the action of complement fragments, arachidonic acid metabolites, formyl ...

It has been suggested that the types of inflammatory round cell infiltrates and the divergence in the cytokine production profile by macrophages and helper T cells regulate the course of infectious or inflammatory diseases, including periodontitis and gingivitis. We examined the expression of IL-1alpha, IL-1beta, IL-2, IL-4, IL-5, IL-6 and ...

Fibroblasts have been studied extensively for their contribution to connective tissue destruction in diseases where the metabolism of extracellular matrix components plays an essential part in their pathogenesis. A considerable dissolution, especially of collagen fibrils, is a well-known characteristic of the periodontal ligament and the gingival connective tissue in microbial-induced ...

It is believed that the degree of periodontal tissue breakdown and tooth loss increase with age. In periodontal tissues which are gingiva, periodontal ligament (PL), alveolar bone and tooth cementum, the PL which is soft connective tissue, lies between the tooth cementum and alveolar bone, having the primary function of ...

A review of phagocytic cells-polymorphonuclear leukocytes and monocytes-in the inflammatory process is presented. Examples of phagocyte defect-related pathology serve as a framework for understanding the role of these cells in periodontal infection. The role of alterations in neutrophil function in localized juvenile periodontitis is presented as a model system for ...

Gingivitis and periodontitis are thought to result from an imbalance between those oral microorganisms which normally colonize tooth surfaces in close contact with the gingival margin, and the nature and efficiency of the host response. The bacteria are the triggering agents, but host defence mechanisms within the gingival/periodontal tissues seem ...

Pro-inflammatory cytokines such as interleukin (IL)-1, IL-6, IL-8 and tumour necrosis factor (TNF) are believed to be the major pathological mediators of inflammatory diseases ranging from arthritis to the periodontal diseases. The stimuli inducing proinflammatory cytokine induction in the former disease is unclear but in the periodontal diseases it is ...

The purpose of this study was to examine the antigenic abilities of Fusobacterium nucleatum strain ATCC 25586 and Porphyromonas gingivalis strain W50 black inbred BALB/cABom mice immunized subcutaneously. Furthermore, we aimed to analyze whether the outer membranes (OM) and whole cells (WC) of F. nucleatum or P. gingivalis had an ...

Periodontitis is a chronic inflammatory disease of the soft and hard supporting tissues of the teeth and is a major cause of tooth loss in adults. The local host response to periodontopathic bacteria results in the release of inflammatory mediators and cytokines. Since cytokines are indicative of effector functions, we ...

OBJECTIVE: Periodontitis is a disease showing differences in disease progression between patients and between sites within a patient. Routine clinical examinations today are not useful enough to distinguish susceptible patients and active lesions from resistant patients and chronic lesions. Diagnostic markers should be pathogenic and inflammatory factors participating in periodontal ...

BACKGROUND: Cellular immunity has been implicated in periodontal destruction for over 25 years. Studies in the 1970s used lymphocyte transformation and lymphokine assays to establish a role for cell-mediated mechanisms in periodontal disease. Immunohistological studies subsequently showed that the formation of gingivitis followed a similar pattern to the formation of ...

Orthodontics is based upon the cellular response to biomechanical forces. However, little is known about the way cells respond to such forces. An experimental model has been designed to study the morphological and metabolic behaviour of human cells, subjected to cyclical or static mechanical loads. The model involves attaching human ...

Bacteria can indirectly affect the course of periodontal diseases by activating host cells to produce and release inflammatory mediators and cytokines. These mediators and cytokines manifest potent proinflammatory and catabolic activity and may play key roles in local amplification of the immune response as well as in periodontal tissue breakdown. ...

Inflamed gingival tissues are enriched in macrophages (MOs) and CD4-positive T cells; however, T helper-type cytokines such as interleukin (IL)-2 and IL-4 are absent. Therefore, we investigated whether a relationship exists between IL-4 receptor (IL-4R) expression and MO persistence in the absence of exogenous IL-4. Gingival MOs, when compared with ...

This review focuses on two topics that in the past decade have significantly enhanced our understanding of the mechanisms by which bacteria produce disease in humans: population structures of bacterial pathogens and tactics used by these bacteria to gain entry to mammalian cells. Studies in these areas have identified a ...

A large number of potential regulatory mechanisms have been described which may be involved in the control of cell function in the periodontium. In this review, soluble effector molecules which may regulate normal cell turnover and which may control the maintenance of the periodontal space are considered. There is evidence ...

BACKGROUND: Cytokines are important regulatory proteins, produced by activated cells, which act by binding high affinity cell surface receptors. They are involved in almost all aspects of cell biology and form interacting networks, with cascades of sequential cell activation. They often show overlapping activities (redundancy) or the same cytokine may ...

The gram-negative bacterium Actinobacillus actinomycetemcomitans is considered an important etiological agent in periodontal diseases. In this study, we show that A. actinomycetemcomitans strains are cytotoxic for the murine macrophage cell line J774.1. On the other hand, Porphyromonas gingivalis strains, other gram-negative oral species implicated in adult periodontitis, showed weak cytotoxic ...

Periodontitis and gingivitis are chronic inflammatory diseases of the periodontium and adjacent tissues. This site-specific inflammation is characterized by a local infiltration of polymorphonuclear leukocytes and T lymphocytes. Interleukin-8 is a low molecular-weight cytokine that is thought to be responsible for the induction and maintenance of localized inflammation. We hypothesized ...

The effect on B-lymphocytes of butyric acid, a metabolic by-product formed by selected anaerobic bacteria of the subgingival plaque and present in mM amounts in the crevicular fluid of patients affected by adult periodontitis was investigated. A dose-dependent inhibition of both mitogenesis and Ig production in B-cells challenged with formalinized ...

The known actions of cytokines suggest that these molecules hold a great potential for modulating the host immune response and enhancing tissue regeneration. These molecules would be useful in controlling the adverse effects of the host immune response and/or augmenting the regenerative potential of cytokines. Once the technology is optimized, ...

I hypothesize that chronic reduced microcirculation, even limited to micro areas of tissue, may lead to respiratory deficiencies, to a proliferation of simplified cells as a result of a lack of energy, and to defects in immune control. In these situations, reduce resistance and specific hypofunction might occur in organs ...

Histological studies have revealed elevated levels of T and B lymphocytes in inflamed gingival tissue. Functional analysis of these B cells has determined that they are spontaneously secreting large amounts of immunoglobulin. Several components of bacterial plaque which accumulate during the onset of periodontal disease induce polyclonal B cell activation, ...

In response to periodontal pathogens neutrophils release oxidants, proteinases, and other destructive factors. The balance between these factors, the antioxidants, and endogenously synthesized antiproteinases determine the extent of periodontal damage. Malnutrition, particularly protein-energy malnutrition involving concomitant deficiencies of antioxidant nutrients, is characterized by impairment in production and cellular actions of ...

Chronic periodontitis is a major cause of tooth loss in adults and is a consequence of the colonisation of the subgingival region by organisms such as Porphyromonas gingivalis, Prevotella intermedia and Fusobacterium nucleatum. Lipopolysaccharide (LPS) is a constituent of the cell walls of all of these bacteria and is found ...

In response to periodontal pathogens, the leukocytes (PMN) elaborate destructive oxidants, proteinases, and other factors. The balance between these factors, the antioxidants and endogenously synthesized antiproteinases determine the extent of periodontal damage. Malnutrition (PEM) is characterized by marked tissue depletion of the key antioxidant nutrients, including GSH (gamma-glutamyl-cysteinyl-glycine), and impaired ...

Multiple mechanisms are involved in the pathologic changes associated with formation of acute and chronic periradicular lesions. Mechanical injury to the periradicular tissues can cause activation of several pathways of inflammation and release of nonspecific mediators. Continuous irritation of periradicular tissues can cause activation of several pathways of inflammation and ...

To a considerable extent, host factors condition the initiation and progression of periodontitis. The integrity of the periodontal structures and the immune elements in the gingival fluid may act as a defensive barrier against microorganisms. However, immune over-response may lead to tissue damage and bone resorption from anaphylactic reactions, immunocomplex ...

This review article highlights the evidence supporting the concept that, like lymphocytes, fibroblasts also consist of subpopulations with unique phenotypes and functions. A new view of the fibroblast is that they are dynamic and consist of subsets which produce cytokines and interact with the immune system. For example, murine lung ...

Periodontal diseases have been considered as "infections" in which micro-organisms initiate and maintain the destructive inflammatory response. Host-mediated tissue destruction occurs via complement activation and the release of lysosomal enzymes, and connective tissue matrix metalloproteinases. Microbial enzymes may damage connective tissues directly, and, together with toxic metabolites and structural materials, ...

The lack of precise clinical criteria for assessment of periodontal disease has led to a search for alternative means of determining active disease sites, prognosis of future sites of breakdown, and response to therapy. This review highlights the potential array of biomarkers present in gingival crevicular fluid and which may ...

Porphyromonas gingivalis produces a variety of virulence factors that may have a function in the periodontal disease process. Determination of the role of these various factors in pathogenesis and identification of a means for protecting the host from the destructive effects of this organism are areas of vigorous investigation. In ...