structure and composition
In many regions, a third layer (the submucosa) is found between the lamina propria and the underlying bone (palate) or muscle (cheeks and lips). The submucosa consists of a looser connective tissue containing the main nerves and blood vessels, as well as glands.
Within the oral cavity about 60% of the mucosa is lining mucosa, about 25% of the mucosa is masticatory mucosa and the remaining 15% is specialized mucosa.
Prickle cell layer
These two epithelia comprise the dentogingival junction; both are non-keratinized.
Crevicular (sulcular) epithelium
The lamina propria associated with the junctional epithelium has a rich blood supply arranged as a complex anastomosing network. This crevicular plexus is the obvious source of gingival crevicular fluid. The vessels of the plexus are very sensitive to stimulation and are likely to vasodilate under the slightest of insults. In response to plaque, they may become more permeable, increasing the production of crevicular fluid.
Principal gingival collagen fibres
The epithelium lining the col is non-keratinized and initially derived from the reduced enamel epithelium. Its epithelium is thin and, as the region is not easy to keep plaque-free, inflammatory cells may be seen infiltrating the underlying lamina propria. When teeth are spaced, the col does not exist and the gingiva here is covered by a keratinized epithelium.
Gingival crevicular fluid
The basement membrane filters out large components.