Immunohistochemical study of structural proteins in. A culture model of development reveals multiple properties. Morphological and functional characteristics of human gingival. The probing depth of the gingival sulcus is measured by a calibrated periodontal probe. The attachment of cells against the tooth is a central function of the junctional epithelium je to seal the periodontium.
As the tooth erupts, the superficial portion of the attachment progressively separates from the enamel, leaving a cuticle adherent to the tooth surface and forming. Growth and development considerations in the diagnosis of gingivitis and periodontitis in children enrique bimstein, cd lars matsson, dds dr. Very quickly, as occurs in the embryologic development of gastric epithelium see chapter 3, foveolar pits form, resulting in movement of the stem cells to the deep. The je mediates the attachment of gingiva to the teeth through hemidesmosomes and the internal basal lamina with a unique basement membrane bm composition, while being attached to the connective tissue by the external basal lamina. This biological seal forms a barrier against pathogens whilst still enabling diffusion of molecules. For human teeth to have a healthy oral environment, all parts of the tooth must develop during appropriate stages of fetal development. There are three characteristic types of epithelial cells. Read regeneration of junctional epithelium and its innervation in adult rats. Both the sulcular epithelium and junctional epithelium are difficult to see in clinical examination of healthy gingival tissue. The junctional epithelium forms with the eruption of tooth crown into the oral cavity 6.
Morphological and functional characteristics of human gingival junctional epithelium qian jiang, youcheng yu, hong ruan, yin luo and xuehua guo abstract background. The junctional epithelium je adjacent to the tooth is that part of the gingiva which attaches the connective tissue to the tooth surface fig. Junctional adhesion molecules jama, b and c are cellcell adhesion molecules of the immunoglobulin superfamily which are expressed by a variety of tissues, both during development and in the adult organism. Epithelia exhibit considerable differences in their histology. Pdf biological characteristics of junctional epithelium. Bmc oral health morphological and functional characteristics of human gingival junctional epithelium qian jiang 0 youcheng yu 0 hong ruan 0 yin luo 0 xuehua guo 0 0 department of stomatology, zhongshan hospital fudan university, 180 fenglin road, shanghai 200032, china background. These results suggest a relationship between expression of structural proteins and changes during development and differentiation of ameloblasts to junctional epithelial cells.
Zo1 expression then decreased when junction permeability presumably continued to decrease. The conversion of junctional epithelium to pocket epithelium is regarded as a hallmark in the development of periodontitis. During tooth development, the inner enamel epithelium differentiates into. Therefore, longjunctional epithelium developed, and gingival recession occurred, since a periodontal pocket did not develop with age in either strain. As the tooth actively erupts, the coronal part of the fused and surrounding. In contrast to the many recent and contemporary textbooks on oral and dental tissues, the present chapter is designed to deal separately with each of the periodontal tissues in terms of their developmental, structural, biochemical, and functional aspects, i. The ultrastructure of the ciliary epithelium of the ciliary body. Prominent developmental features include a transition from predominantly nonciliated to ciliated cells, quantitative and qualitative changes in secretion of macromolecules, and a transition from secretory to absorptive patterns of ion transport. The epithelial attachment and the dental junctional epithelium. We also analyzed the tj permeability of the rat colon epithelium prior to the development of tumors, and correlated it with the presence of aberrant crypts.
The antimicrobial defense mechanisms of the junctional epithelium, however, do not preclude the development of gingival and periodontal lesions. The junctional epithelium originates from the odontogenic. Junctional epithelium is derived from the reduced enamel epithelium during tooth development. The resistance to probing following root planing and soft tissue curettage appears to result from the formation of a long junctional epithelium rather than new connective tissue attachment. It is the tissue that arises first in embryonic development, and it is only from epithelium that mesenchyme arises by the socalled epithelialmesenchymal transition, or emt, which is largely a suppression of the factors that cause epithelial differentiation. Before the eruption of the tooth and after enamel maturation, the ameloblasts secrete a basal lamina on the tooth surface that serves as a part of the primary ea. During development, reduced enamel epithelium fuses with oral epithelium and forms along crown to level of cej. Junctional epithelium is derived from the reduced enamel epithelium ree during tooth development. Enamel is a formidable bioceramic designed to withstand enormous mechanical forces for decades while being subjected to constant changes in temperature, ph and microbial challenges, all that without the ability to regenerate. To explore the development of tight junctions, the current study refined a previous culture model of early rpe development 23. Epithelia exhibit considerable differences in their histology, thickness and. The junctional epithelium is formed by the confluence of the oral epithelium and the reduced enamel epithelium during tooth eruption however, the reduced enamel epithelium is not essential for its formation.
Quantitative analysis of tight junctions during ciliary epithelium development. Introduction junctional epithelium development of junctional epithelium structure epithelial attachment dynamic aspects of junctional epithelium expression of various molecules and their functions permeability functions regeneration role of. Increased tight junctional permeability is associated with. Development of tight junctions in the human ciliary epithelium. Visualization of junctional epithelial cell replacement by oral gingival. Primary baby teeth start to form between the sixth and eighth week of prenatal development, and permanent teeth begin to form. Functions dynamic aspects of junctional epithelium regeneration role of je in initiation of pocket formation junctional epithelium around implants.
The endocervix is lined by a simple columnar epithelium that secretes mucus. The results of this study indicated that this model system cannot be used. Comprehensive analysis of gene expression in the junctional epithelium by laser microdissection and microarray analysis. In the developing tooth, two layers of cells, the inner layer of ameloblast and outer layer of cuboidal cells, remain as the reduced enamel. Gingival sulcus may develop between the gingiva and the surface of the tooth and extend around its circumference. The study explains, collectively, these studies all appear to support the vital importance of unimpeded absorption, adhesion and maturation of the fibrin clot for formation of a connective tissue attachment over a long junctional. The junctional epithelium is the epithelial component of the dentogingival unit that is in contact with the tooth surface. The conversion of the junctional to pocket epithelium, which is regarded as a hallmark in disease initiation, has been the focus of intense research in recent years.
Disruption of the seal can lead to gingivitis and periodontitis. E12 stained ameloblasts and all layers of reduced enamel epithelium and junctional epithelium in all stages of development. The junctional epithelium je is attached to the tooth surface by. The junctional epithelium je is an epithelial component that is directly attached to the tooth surface and has a protective function against periodontal diseases. Mucinous columnar epithelium lines the surface and the. Bampton jl, shirlaw pj, topley s, weller p, wilton jm. The antimicrobial defense mechanisms of the junctional epithelium, however, do not preclude the development of gingival and periodontal. Article information, pdf download for the junctional epithelium. Apoptosis occurs in the border between oral and reduced enamel epithelia during tooth eruption. Aberrant crypts were quantified at various time points within the 18 weeks of dmh treatment and it was noted that there was a progressive increase in the number of aberrant crypts as a.
Growth and development considerations in the diagnosis of. Meanwhile zo1 gradually appeared and its expression peaked on e10. The squamous epithelium is composed by multiple layers. In addition, the cellular dynamics of the epithelium were also evaluated at the end of three and six mo. Regeneration of junctional epithelium and its innervation.
There are three types of mucous membranes masticatory, lining, and specialized line the oral cavity and form the structural boundary between the body and the external environment. This study aims to observe the morphological characteristics and identify the function characteristics of. Gingival and dentogingival junctional tissue pocket. The term junctional epithelium denotes the tissue that is affixed to the tooth on one side and to the oral sulcular epithelium and connective tissue on the other side 17, 100. Development, structure, and function of periodontal. The conversion of the junctional to pocket epithelium, which is regarded as a hallmark in disease initiation. Bimstein is a professor, department of pediatric dentistry, faculty of dental medicinehadassah school of dental medicine, hebrew university in jerusalem, israel. In vitro reconstruction of human junctional and sulcular. This clot transforms into a long junctional epithelium, clinically realized as pockets with reduced depths. Junctional epithelium epithelium cell biology free. The apical and basal environments of the retinal pigment. Knowledge of factors contributing to the initiation and progression of pocket formation is important and may result in the development of better preventive measures and improve healing outcomes after therapeutic interventions. Development of junctional epithelium according to gottlieb, the reduced enamel epithelium that covers the crown fuses with the oral epithelium and becomes the epithelial attachment.
This study asks how closely the culture model reflects normal development and how the composition, structure and function of embryonic tight junctions are affected by the apical and basal environments. The dynamics of the long junctional epithelium in rat gingivae were observed over a period of from three to six mo. The surface epithelium of newborn ferret airways matures rapidly in the first month of life. Junctional epithelium an overview sciencedirect topics. It forms a band 23 mm wide around the tooth, and is approximately 1530 cells thick coronally and tapers to a single cell apically. In a healthy situation, it averages approximately 2 mm in height. Agerelated development of the longjunctional epithelium. Tooth development or odontogenesis is the complex process by which teeth form from embryonic cells, grow, and erupt into the mouth. The crevicular epithelium, or sulcular epithelium, stands away from the tooth, creating a gingival sulcus, or space that is filled with gingival crevicular fluid gcf see figure 101. In fact, epithelium is the default state of cells in the eumetazoa. In particular, there was a strong correlation between the jed and age in both strains r 0.
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