Page 538 - Textbook of Pathology, 6th Edition

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The Oral Cavity and
Chapter 19
Chapter 19
Salivary Glands

ORAL SOFT TISSUES iv) Bifid tongue is a rare condition occurring due to failure
of the two lateral halves of the tongue to fuse in the midline.
v) Tongue tie occurs when the lingual fraenum is quite
NORMAL STRUCTURE
short, or when the fraenum is attached near the tongue tip.
The oral cavity is the point of entry for digestive and vi) Hairy tongue is not a true developmental defect, but is
respiratory tracts. The mucous membrane of the mouth mentioned here because of its similarity with other
consists of squamous epithelium covering vascularised conditions discussed here. The filiform papillae are
connective tissue. The epithelium is keratinised over the hard hypertrophied and elongated. These ‘hairs’ (papillae) are
palate, lips and gingiva, while elsewhere it is non-keratinised. stained black, brown or yellowish-white by food, tobacco,
Mucous glands (minor salivary glands) are scattered oxidising agents or by oral flora.
throughout the oral mucosa. Sebaceous glands are present
in the region of the lips and the buccal mucosa only. MUCOCUTANEOUS LESIONS
Lymphoid tissue is present in the form of tonsils and
adenoids. Lesions of the oral mucosa occur in many diseases of the
The oral cavity is the site of numerous congenital and skin (Chapter 26) and they are similar in morphology. Some
acquired diseases. Besides, many systemic diseases have oral of these are listed as under:
manifestations. Some of the commonly occurring conditions LICHEN PLANUS. Characteristically, oral lichen planus
are discussed here. appears as interlacing network of whitening or keratosis on
the buccal mucosa but other oral tissues such as gingival,
SECTION III
DEVELOPMENTAL ANOMALIES tongue and palate may also be involved.
1. FACIAL CLEFTS. Cleft upper lip (harelip) and cleft palate, VESICULAR LESIONS. A number of vesicular or bullous
alone or in combination, are the commonest developmental diseases of the skin have oral lesions.
anomalies of the face. These occur from the failure of fusion i) Pemphigus vulgaris. Vesicular oral lesions appear
of facial processes.
invariably in all cases at some time in the course of
2. FORDYCE’S GRANULES. Fordyce’s granules are pemphigus vulgaris. In about half the cases oral lesions are
symmetric, small, light yellow macular spots on the lips and the initial manifestations.
buccal mucosa and represent collections of sebaceous glands. ii) Pemphigoid. Vesicles or bullae appear on oral mucosa
They remain undeveloped until puberty but occur quite as well as on conjunctiva in pemphigoid and are seen more
commonly in adults. often in older women.
Systemic Pathology
3. LEUKOEDEMA. This is an asymptomatic condition iii) Erythema multiforme. Subepithelial vesicles may occur
occurring in children and is characterised by symmetric, grey- on the skin as well as mucosae.
white areas on the buccal mucosa. Histologically, there is iv) Stevens-Johnson syndrome is a rather fatal and severe
pronounced intracellular oedema. There is no increased form of erythema multiforme involving oral and other
malignant potential compared to leukoplakia discussed mucous membranes occurring following ingestion of sulfa
below. drugs.
4. DEVELOPMENTAL DEFECTS OF THE TONGUE. v) Epidermolysis bullosa is a hereditary condition having
These are as under: subepidermal bullae on the skin as well as has oral lesions.
i) Macroglossia is the enlargement of the tongue, usually
due to lymphangioma or haemangioma, and sometimes due INFLAMMATORY DISEASES
to amyloid tumour. STOMATITIS. Inflammation of the mucous membrane of
ii) Microglossia and aglossia are rare congenital anomalies the mouth is called stomatitis. It can occur in the course of
representing small-sized and absence of tongue respectively. several different diseases.
iii) Fissured tongue (scrotal, furrowed or grooved tongue) i) Aphthous ulcers (Canker sores) is the commonest form
is a genetically-determined condition characterised by of oral ulceration. The etiology is unknown but may be
numerous small furrows or grooves on the dorsum of the precipitated by emotional factors, stress, allergy, hormonal
tongue. It is often associated with mild glossitis. imbalance, nutritional deficiencies, gastrointestinal