Gingival epithelium

This chapter describes the organization of the major proteins that form a basal lamina which connects an epithelium to its underlying stroma (Sect. 1). The organization and major protein composition of oral and gingival epithelium and the junctional epithelial dental attachment at the base of a gingival sulcus are described (Sect. 2). 

Figure 26.2 The dentogingival junction showing three types of gingival epithelium, oral, oral sulcular and junctional, and the diminishing degrees of keratinization (as denoted by diagonal hatching)...

Fig. 16. Acrylamide gel patterns of collagen subjected to colli enase derived from human gingival tissues, gingival epithelium only, and ngival connective tissues only. The characteristic control pattern on the left depicts the two o-chains and the two /I-chains (dimers of a..chains) obtained after urea denaturation. In. addition to these two layers, collagen solutions digested by eollagenase from gingival tissues and sub. scquciitly denatured display two layers representing the approximate 3/4 pieces...

What is the main structural difference between the gingival and the cheek epithelium ... 

Local factors, systemic factors, or a combination of both can cause halitosis. It is estimated that 80%i of all mouth odors are caused by local factors within the oral cavity, and these odors are most often associated with caries, gingivitis, and periodontitis. Oral malodors occur because of the action of various microorganisms on proteinaceous substances, such as, exfoliated oral epithelium, salivary proteins, food debris, and blood.t ]... 

Analysis of in vivo-formed pellicle by a combination of electrophoretic separation and MALDI-TOF showed the presence of intact histatin 1, cystatin SN, statherin, lysozyme, albumin and amylase [15, 39], In addition, intact cytokeratins 13 and 15 and calgranulin B were identified as components of the salivary pellicle layer for the first time using MALDI-TOF mass spectrometry [15]. Calgranulin B has been shown to be a component of saliva and gingival crevicular fluid [15]. The identification of cytokeratins in the salivary pellicle layer points to the oral epithelium as one of the sources of proteins adsorbed on the tooth surface. 

The basal cells of a layered epithelium such as skin or gingiva (Sect. 5.2.1), or the periosteal cells covering bone, have such high nutrient demands that they need to be close to a rich capillary bed. Thus, although capillaries permeate the stroma, they are especially dense beneath the basal lamina of a layered epithelium (Sect. 13.3.1) or within a periosteum (Sect. 9.2.1). The gingival-tooth interface is especially susceptible to bacterial agents that... 

At the base of a gingival sulcus, the junctional epithelium mediates the epithelial attachment. This epithelium possesses two basal laminas, an outer one that is continuous with the sulcular epithelium around the free gingiva and an inner one which mediates the actual... 

In gingivitis, IL-1 production by PAMP activation of external and cytosolic PRRs is maximal within the junctional epithelium. As little as 0.1 ng/mL of IL-1 will bind to and activate IL-1 receptors in capillary endothelium where they (a) Open intercellular junctions allowing plasma to exude (b) Promote secretion of plasminogen activator to prevent the plasma fluid exudate from clotting in the stroma (Sect. 11.4.2) (c) Induce intercellular adhesion molecule-1 (ICAM-1) to arrest and transfer neutrophils from blood to the exudate and D) Induce TNF-a to enhance ICAM-1 and VEGF production. 

Aggressive periodontitis occurs in less than 0.1% of the US population. ANUG is a form of aggressive periodontitis in which stress hormones may overactivate TLRs to PAMPs around and within cells at the base of gingival sulci. The junctional epithelium fragments and its cells release their contents necrosis). The necrotic cell contents induce a massive release of pro-inflammatory cytokines that cause apoptosis of adjacent cells and a heavy infiltrate of leukocytes from more distant cells. Neutrophils and monocytes invade and destroy the surrounding periodontal attachment and alveolar bone. 

However, the effect depends on the source of the fibroblasts. Gingival fibroblasts are useful as autologous transplant cells for tracheal epithehal regeneration (comparable to the epithehum induced by tracheal fibroblasts), whereas nasal and dermal fibroblasts could not serve this function [73]. Other studies have used human xenograft cells in animal models, in particular in the nude mice, to show that human airway cells implanted in such conditioned can regenerate a well-differentiated and functional human epithelium [48,74,75]. 

Dietary factors appear to be of less importance in periodontal disease which results from gingivitis, an inflammatory condition produced by local irritants. The dietary consistency is, however, of some importance since foods that have a firm consistency increase the gingival circulation and promote keratinization of the epithelium. The formation of a thick horny layer provides protection against chemical and bacterial irritants, but if the diet is excessively coarse and granular it can have an adverse effect by causing inflammation through over-use or actual injury to the periodontal tissue. 

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