Oral mucosa

[2] Changes indicative of disease are seen as alterations in the oral mucosa lining the mouth, which can reveal systemic conditions, such as diabetes or vitamin deficiency, or the local effects of chronic tobacco or alcohol use.

Nonkeratinized squamous epithelium covers the soft palate, inner lips, inner cheeks, the floor of the mouth, and ventral surface of the tongue.

Nonkeratinized epithelium may, however, readily transform into a keratinizing type in response to frictional or chemical trauma, in which case it undergoes hyperkeratinization.

This change to hyperkeratinization commonly occurs on the usually nonkeratinized buccal mucosa when the linea alba forms, a white ridge of calloused tissue that extends horizontally at the level where the maxillary and mandibular teeth come together and occlude.

In patients who have habits such as clenching or grinding (bruxism) their teeth, a larger area of the buccal mucosa than just the linea alba becomes hyperkeratinized.

This larger white, rough, raised lesion needs to be recorded so that changes may be made in the dental treatment plan regarding the patient's parafunctional habits.

Thus, to check for malignant changes, a baseline biopsy and microscopic study of any whitened tissue may be indicated, especially if in a high-risk cancer category, such with a history of tobacco or alcohol use or are HPV positive.

[10] The lamina propria is a fibrous connective tissue layer that consists of a network of type I and III collagen and elastin fibers in some regions.

Typically, regions such as the cheeks, lips, and parts of the hard palate contain submucosa (a layer of loose fatty or glandular connective tissue containing the major blood vessels and nerves supplying the mucosa).

In regions such as the gingiva and parts of the hard palate, oral mucosa is attached directly to the periosteum of underlying bone, with no intervening submucosa.

Management includes identifying and addressing contributory factors, the use of topical/systemic anti-fungal agents, oral and denture hygiene instruction.

Schematic illustration of the layers found in keratinized oral mucosa that include a deeper lamina propria and basement membrane in-between and superficial layers of strafied squamous epithelium that include from deepest to most superficial:
1: Stratum basale
2: Stratum spinosum
3: Stratum granulosum
4: Stratum corneum