Hist 12 lab
- 13. Histology of gingiva The gingiva is covered with Keratinized Stratified squamous. This epithelial layer shows projections into the underlying Connective tissue which are known as Rete Pegs projections. The epithelium has 4 layers: 1- SC: Stratum Corneum-The cells are flattened, outermost layer. 2- SG: Stratum Granulosum-The cells contain granules and are relatively bigger in size. 3- SS: Stratum Spinosum-The cells are large polyhedral in appearance. It is also named prickle cell layer. 4- SB: Stratum Basale-The cells are rounded and these are the proliferative cells which give rise to new cells.
- 14. Cells: In addition to the defense cells, different types of cells which are present in the gingiva apart from the normal epithelial cells are: 1- Melanocytes: They are the cells which give the darkish color of gingiva in some individuals (dark skinned individuals). 2- Langerhan Cell: These are the modified macrophages which help in producing antigens. 3- Merkel cell: these are present in the deep layers and act as tactile proprioceptive cells.
- 15. Fibers: The fibers are present in the connective tissue underneath the epithelium. Fibers are mainly: 1- Collagen Fibers: Type VII collagen fibers are predominant which are present in intimate contact with basal lamina. Type IV collagen fibers present in basal linings of epithelial walls and blood vessels. 2- Elastin Fibers: Rare in lamina propria and common in lining mucosa, the elastic fibers are made up of Elastin: provide elastic nature Fibrillin: 3- Oxytalin Fibers: These resemble immature elastic fibers.