Читать книгу Periodontics - Fernando Suarez - Страница 15

The oral mucosa is composed of the mucosal tissues that cover the mouth, and it can be classified as masticatory mucosa (gingiva and hard palate), lining mucosa (alveolar mucosa, floor of the month, and internal surface of lips), and specialized mucosa (tongue). The lining or alveolar mucosa extends inside the cheeks, floor of the mouth, as well as soft palate, and it is characterized by the presence of a basal layer (which is positive to the expression of keratin 5, 14, and 19), an intermediate layer, and a superficial layer expressing keratin 13 and 4.¹⁴

The gingiva (masticatory mucosa) is composed of free gingiva and attached gingiva, and it is characterized by the presence of keratin in the most superficial layer. Histologically, four layers of cells have been described (Fig 1-1):

Fig 1-1 Layers of keratinized gingiva.

1 Stratum basale, which is characterized by the expression of keratin 5 and 14

2 Stratum spinous, named due to the spinous morphology of the cells in this layer

3 Stratum granulosum, characterized by the presence of round cytoplasmic granules

4 Stratum corneum with cornified cells

Gingiva has different names and presents with slight morphologic differences depending on the tissue that it covers (ie, free gingiva or attached gingiva; Fig 1-2).

Fig 1-2 The gingiva.