Dental Implant Infection: Typical Causes and Control
Huiliang Cao in Silver Nanoparticles for Antibacterial Devices, 2017
The proliferative capacity of the junctional epithelium leads to the rapid migration of the epithelial cells as soon as the fibrin clot/granulation tissue starts forming at the implant installation. Once the cells reach the implant surface, their attachment occurs rapidly through the basal lamina and the hemidesmosomes. Another possible attachment modality hypothesised is an indirect epithelium to implant contact. The peri-implant sulcus shares structural, ultrastructural and functional characteristics with the gingival tissues. Human studies have demonstrated that epithelium surrounding dental implants possesses similar patterns of differentiation and function to gingival tissues. The presence of granulation tissue adhering to the surface of the transmucosal components is considered the principal factor that stops the epithelium from migrating down apically. Berlundh speculated that the epithelium not migrating down apically is likely attributed to the interaction between the titanium oxide film and the collagenous connective tissue. A further explanation for the limitation of the proliferation of the junctional epithelium could be the increased fibroblasts over a width of approximately 40 μm in the area of the inner zone, as histologically proven in an animal experimental investigation.
Pathogenesis of Odontogenic Cysts
Roger M. Browne in Investigative Pathology of the Odontogenic Cysts, 2019
These two types of cyst have many clinical and histological features in common (see Chapters 1 and 2) and it has been suggested that they represent extra- and intraosseous variants of the same condition,28 although this view is not supported by others.29,30 While a common epithelial origin for the lateral periodontal cyst and, at least some adult gingival cysts, has received much support,28,30–32 the identity of that epithelium is still unclear. An origin from the cell rests of the dental lamina28 requires a hypothesis that these cysts and odontogenic keratocysts originate from different cells of the dental lamina with different capacities for differentiation and with different growth potentials. This is conceivable as ultrastructural studies have shown that cells of the proliferating dental lamina vary in structure in different parts.33 Epithelial rests are quite common in specimens of adult gingiva, the incidence varying from 3434 to 58%.35 The proximity of the epithelial lining of gingival cysts to the junctional epithelium of the adjacent tooth, prompted the hypothesis of a possible origin from this latter epithelium.32 It has been further proposed36 that lateral periodontal cysts may arise by eruption of a tooth past a laterally positioned dentigerous cyst. These two hypotheses have the attraction that they suggest a common origin for the epithelial lining of the two cyst types, the reduced enamel epithelium. As this is a post functional epithelium, it might more appropriately explain the indolent behavior of these cysts.
Gingiva and Periodontal Tissue Regeneration
Vincenzo Guarino, Marco Antonio Alvarez-Pérez in Current Advances in Oral and Craniofacial Tissue Engineering, 2020
Among these cells, the first three types are responsible for regenerating the periodontal tissue, while the last type—i.e., epithelial cells—are responsible for soft tissue regeneration. It is worth mentioning that the higher migration rate of epithelial cells (10 times faster) in comparison to the other periodontal cell types is the reason for observing the formation of the long junctional epithelium in the periodontal therapy (Engler et al. 1966). Infiltration of epithelial cells inside the defect can promote repair by the formation of an unusual architecture with a loss of function (Caton et al. 1987). Therefore, guided tissue membranes are implanted to limit the infiltration of the epithelial cells (Nyman et al. 1987). If epithelial cells are ruled out from the wound, other cell types with regenerative potential are thus allowed to become established, and epithelial down-growth can be successfully prevented (Linde et al. 1993). A combination of bonegraft materials, promoting the migration and differentiation of osteoblast cells, and GTR is the most commonly-used approach for achieving an optimal periodontal regeneration (Frost 1989a; Frost 1989b). Two reasons have been identified behind this synergic activity, i.e., the biological effects of bone grafts and the `Melcher hypothesis’, which explains the importance of cells used for the periodontal regeneration. According to this hypothesis, the origin of cells dictates the nature of the attachment in periodontal healing and the complete periodontal regeneration may be achieved when we apply cells with an origin from the periodontal ligament and the perivascular bone cells (Aurer and Jorgie-Srdjak 2005; Koop et al. 2012).
Critical roles of adherens junctions in diseases of the oral mucosa
Published in Tissue Barriers, 2023
Christina Kingsley, Antonis Kourtidis
The gingival epithelium has been extensively studied due to its implication in periodontal disease. The gingival epithelium is composed of keratinizing stratified epithelium and covers the external surface of the gingiva, which surrounds the teeth (Figure 1).6 An important function of the gingival epithelium is to provide the first line of defense in the oral cavity against pathogens.7 There are several components of the gingiva. The attached gingiva is firmly bonded to the connective tissue over the alveolar bone and is separated from the oral mucosa by the mucogingival line (Figure 1). The attached gingiva is located apically to the gingival sulcus, which is the space surrounding each tooth and is lined by the oral sulcular epithelium (Box 1; Figure 1). This epithelium is stratified and non-keratinized.2 The junctional epithelium is a specialized epithelial component. This epithelium is derived from the enamel epithelium and mediates the attachment of the gingival epithelium to the enamel on the tooth surface (Figure 1).8 This is an important function of the junctional epithelium, because it forms a barrier against pathogens passing from the oral cavity into the tissue that supports the tooth.9 Due to its role, the junctional epithelium isan area of extensive study in periodontal disease,10 where tooth mobility and loss are found. In comparison to the gingival epithelium, the junctional epithelium shows no keratinization and exhibits much higher proliferation and turnover rate2,7,8 (Figure 1).
Polyamine biomarkers as indicators of human disease
Published in Biomarkers, 2021
Mohsin Amin, Shiying Tang, Liliana Shalamanova, Rebecca L. Taylor, Stephen Wylie, Badr M. Abdullah, Kathryn A. Whitehead
The GCF is an oral inflammatory exudate, which is derived from the periodontal tissues and is found in the sulcus between the tooth and the gingiva (Lamster 1997, Subbarao et al.2019). Its role is to facilitate the antimicrobial defence of the periodontium and to maintain the structure of the junctional epithelium (Subbarao et al.2019). Under normal conditions, GCF is sourced in small volumes of 0.43–1.56 µL/h (Khurshid et al.2017). However, the amount of GCF produced significantly increases, up to 44 µL/h in response to stimuli from the immune system and during periodontal disease. The constituents of GCF originate from the blood, surrounding cells and the various tissues of the periodontium (Lamster and Ahlo 2007). Although the role of GCF is to prevent microbial mediated damage to the oral cavity, an increase in GCF has been shown to increase localized nutrients and provide a suitable physical environment for periodontal microorganisms, thus developing a positive feedback loop (Hickey et al.2020).
Gingival epithelial barrier: regulation by beneficial and harmful microbes
Published in Tissue Barriers, 2019
Naoki Takahashi, Benso Sulijaya, Miki Yamada-Hara, Takahiro Tsuzuno, Koichi Tabeta, Kazuhisa Yamazaki
Distinct from the oral epithelium, the gastrointestinal epithelium is composed of a simple layer of columnar epithelial cells. Goblet cells are a major secretory cellular lineage in the intestinal epithelium, synthesizing and secreting mucin into the intestinal lumen. Among other lineages of intestinal epithelial cells, enterocytes are involved in nutrient absorption and immunoglobulin secretion, and Paneth cells can synthesize and produce antimicrobial peptides.23 These specialized epithelial cells are efficient physical and chemical barriers against invading microbes. Unlike the gut, the oral epithelium consists of a stratified squamous epithelium which can be subdivided into three components based on cell morphology: oral epithelium (OE), sulcular epithelium (SE), and junctional epithelium (JE).24 The OE is a keratinizing form of epithelium, providing an effective physical barrier against microbial invasion of the underlying gingival connective tissue. In contrast, SE and JE are dominated by a non-keratinized epithelium,25 which suggests that those epithelia are semipermeable and, thus, allow the transport of macro substances from the gingival sulcus into the underlying connective tissue.
Related Knowledge Centers
- Epithelium
- Gingival Sulcus
- Keratin
- Periodontal Probe
- Stratified Squamous Epithelium
- Tooth Enamel
- Gums
- Glossary of Dentistry
- Sulcular Epithelium
- Gingival Margin