Oral

Developmental defects of the soft tissue

OROFACIAL CLEFTS:

The formation of the face and oral cavity is complex in nature and involves the development of multiple tissue processes that must merge and fuse in a highly orchestrated fashion. Disturbances in the growth of these tissue processes or their fusion may result in the formation of orofacial clefts.

CLEFTS OF THE AND :

Clefts can form in the lip or palate alone or in both. The aetiology is unknown but there is a genetic component in approximately 40% of cases. The risk of having such defects is greatly increased if one, and particularly if both, of the parents are affected.

Classification: Generally, clefts of the lip and palate are classified into 4 major types:

(1) Cleft lip.

(2) Cleft palate.

(3) Unilateral cleft lip and palate.

(4) Bilateral cleft lip and palate.

Nine environmental factors that have been postulated to plan accessory role in the development of cleft lip and palate include

1. Nutritional factors.

2. Physiologic, emotional, or traumatic stress. 3. Relative to the area.

4. Mechanical obstruction by an enlarged tongue.

5. Substances such as alcohol, drugs, or toxins.

6. Infections.

7. Maternal alcohol consumption.

8. Maternal cigarette smoking.

9. Anticoagulants .

Congenital lip pits:

Congenital lip pits are developmental defects that may involve the paramedical portion of the vermillion of the lower and upper lip (paramedical lip pit) or the labial commissure area (commercial lip pit). Both types of lip pits appear to be inherited as autosomal dominant trait. The paramedical lower lip pit may occur as an isolated finding or may be associated with cleft lip or cleft palate (van der woude syndrome). The paramedical lip pits are occasionally excised for cosmetic reasons; commissural lip pits required no treatment.

Double lip:

A double lip is an anomaly characterized by a horizontal fold of redundant mucosal tissue that is usually located on the inner aspect of the upper lip, although the lower lip can also be occasionally involved. This redundant tissue can be congenital or acquired. The double lip is usually visible when the lip is tense but not when the lip is at rest.

Fordyce’s Granules:

Fordyce’s granules represent ectopic sebaceous glands or sebaceous choristomas (normal tissue in an abnormal location). This condition is regarded as developmental and can be considered a variation of normal. Fordyce’s granules are multiple and often are seen in aggregates or in confluent arrangements. Sites of predilection include the buccal mucosa and the vermilion of the upper lip. Lesions generally are symmetrically distributed and tend to become obvious after puberty, with maximal expression occurring between 20 and 30 years of age. Lesions are asymptomatic and often are discovered incidentally by the patient or by the practitioner during a routine oral examination. A large proportion of the population—more than 80% of individual is affected by this particular condition.

Microscopically, lobules of sebaceous glands are aggregated around or adjacent to excretory ducts. The heterotopic glands are well formed and appear functional.

No treatment is indicated for this particular condition because the glands are normal in character and do not cause any untoward effects.

Leukoedema:

Leukoedema is a generalized mild opacification of the buccal mucosa that is regarded as a variation of normal. It can be identified in the majority of the population.

Clinical Features: Leukoedema is usually discovered as an incidental finding. It is asymptomatic and symmetrically distributed in the buccal mucosa and to a lesser extent over the labial mucosa. It appears as a gray-white, diffuse, filmy, or milky surface alteration. In exaggerated cases, a whitish cast with surface textural changes, including wrinkling or corrugation, may be seen. With stretching of the buccal mucosa, the opaque changes dissipate. It is more apparent in nonwhites, especially African Americans. Histopathology: In leukoedema, the epithelium is parakeratotic and acanthotic, with marked intracellular edema of spinous cells. The enlarged epithelial cells have small, pyknotic (condensed) nuclei in optically clear cytoplasm.

Treatment and Prognosis: Treatment is not necessary because the changes are innocuous and no malignant potential exists. If the diagnosis is in doubt, a biopsy can be performed.

White sponge nevus:

Relatively uncommon, autosomal dominant hereditary disorder that manifests as a white lesion of the . The condition exhibits a variable penetrance; some patients exhibit lesion at birth, whereas in others, lesions may not appear until early childhood or even adolescence.

Clinical features: Lesions are asymptomatic, whitish and often folded (corrugated). They may exhibit a translucent opalescence similar to that seen in leukoedema. Lesions may be widespread and involve various sites including the buccal mucosa, gingiva, tongue, palate and floor of the mouth.

Histopathology: a mild to moderate hyperpara keratosis, acanthosis , and intracellular edema of the spinous cells are shrunken (pyknotic). The associated connective tissue is usually free of inflammation. The diagnosis is generally reached by combining its histopathologic features, clinical appearance, and the patient's family history.

Treatment: the condition requires no treatment, because it is entirely benign.

Oral tonsil:

Tonsillar lymphoid tissue is primarily disturbuted in a circular arrangement in the posterior region of the mouth. It consists of three main masses of lymphoid tissue, namely the paired palatine tonsils, the pharngeal tonsils, and the lingual tonsils located at the base of the tongue. The lingual tonsil often extends anteriorly along the postero lateral borders of the tongue and includes the region of the foliate papillae.

Oral tonsils consist of lymphoid aggregate that exhibit germinal centers surfaced by nonkeratinized squamous epithelium, with or without occasional crypts.

Reterocuspeid papilla:

The retrocuuspid papilla is a 2 to 4 mm slightly raised area of mandibular alveolar mucosa located lingual to the cuspids, between the marginal gingiva and the mucogingival junction. It is commonly bilateral but can also be unilateral, and it is prominent in children. Because reterocuspid papilla is commonly bilateral and has a very specific location, it is logical to assume that it represents a normal anatomic structure.

MICROGLOSSIA ():

Microglossia is an uncommon developmental condition of unknown cause that is characterized by an abnormally small tongue. In rare instances, virtually the entire tongue may be missing (aglossia). However, Most reported cases have been associated with one of a group of overlapping conditions known as oromandibular-limb hypogenesis syndromes.

MACROGLOSSIA

Macroglossia is an uncommon condition characterized by enlargement of the tongue. The enlargement may be caused by a wide variety of conditions including both congenital malformations and acquired diseases. The most frequent causes are vascular malformations and muscular hypertrophy.

Causes of Macroglossia

 congenital and hereditary • Down syndrome • Vascular malformations

• Neurofibromatosis • Lymphangioma

• Multiple endocrine neoplasia type 2B • Hemangioma

 Acquired:

• Acromegaly • Edentulous patients

• Carcinoma and other tumors • Amyloidosis

Clinical Features: Macroglossia most commonly occurs in children and can range from mild to severe in degree. macroglossia may be manifested first by noisy breathing, and difficulty in eating. The tongue enlargement may result in a lisping speech the pressure of the tongue against the and teeth can produce a crenated lateral border to the tongue, open bite and mandibular .

ANKYLOGLOSSIA (TONGUE-TIE):

Ankyloglossia is a developmental anomaly of the tongue characterized by an abnormally short and anteriorly positioned lingual frenum that results in severely restricted tongue movements and impaired speech.

Treatment and Prognosis:

Treatment is often unnecessary. If there are functional or periodontal difficulties, a frenectomy may allow greater freedom of tongue movement.

Lingual thyroid nodule: is a rare anomaly characterized by the development of a submucosal mass of thyroid tissue on the mid posterior dorsum of the tongue. Embryologically , the thyroid gland anlage arises at the site of the foramen caecum and migrates inferiorly along the thyroglossal tract to its ultimate destination in the anterior neck. If all or part of the thyroid anlage fails to migrate, remnant of thyroid tissue can develop along its path of migration; a lingual thyroid nodule represents a thyroid remnant in the region of the thyroid gland's origin. .

Clinical features:

It presents as a 2 to 3 cm smooth sessile mass located on the mid posterior dorsum of the tongue, in the foramen caecum. The chief symptoms are , dysphonia, dyspnea, and a feeling of tightness in the area.

Histopathology: most cases are composed of normal mature thyroid tissue although embryonic or fetal thyroid tissue may be seen.

Treatment: before excision of a lingual thyroid nodule is planned, it should be determined if the patient possesses a functioning thyroid gland in the anterior neck with sufficient secretion to support the daily requirement when the supplementary source in the tongue is removed. If a normal thyroid gland is present, then the lingual nodules can be excised.

FISSURED TONGUE (SCROTAL TONGUE)

Fissured tongue is relatively common numerous grooves or fissures are present on the dorsal tongue surface. The cause is uncertain, but heredity appears to play a significant role. Aging or local environmental factors also may contribute to its development.

HAIRY TONGUE ()

Hairy tongue is characterized by marked accumulation of keratin on the filiform papillae of the dorsal tongue, resulting in a hair like appearance; The condition apparently represents an increase in keratin production or a decrease in normal keratin desquamation. Although the cause is uncertain, many affected people are heavy smokers. Other possible associated factors include the following: • Antibiotic therapy • Poor oral hygiene

• General debilitation •

• Use of oxidizing mouthwashes or antacids

• Overgrowth of fungal or bacterial organisms

VARICOSITIES (VARICES):

Varicosities or varices are abnormally dilated and tortuous veins. Age appears to be an important etiologic factor because varices are rare in children but common in older adults. This suggests that their development may be an age-related degeneration in which there is a loss of connective tissue tone supporting the vessels. Oral varices have not been associated with systemic hypertension or other cardiopulmonary diseases.

Sublingual varicosities are typically asymptomatic, and no treatment is indicated. Solitary varicosities of the and buccal mucosa may need to be surgically removed to confirm the diagnosis or for an esthetic purpose.

LATERAL SOFT PALATE FISTULAS:

Lateral soft palate fistulas are rare anomalies of uncertain pathogenesis. Many cases appear to be congenital possibly related to a defect in the development of the second pharyngeal pouch. Some fistulas may be the result of infection or of the tonsillar region.

Clinical Features Lateral soft palate fistulas are usually bilateral, but they may occur only on one side. They are more common on the anterior tonsillar pillar, but they also may involve the posterior pillar, The perforations are typically asymptomatic, ranging from a few millimeters to more than 1 cm. Developmental defects of the Bone

EXOSTOSES:

Exostoses are localized bony protuberances that arise from the cortical plate; these benign growths frequently affect the jaws, the best-known oral exostoses: The and the .

TORUS PALATINUS:

The torus palatlnus is a common exostosis that occurs in the midline of the vault of the hard palate. The pathogenesis of these tori has long been debated with arguments centering on genetic versus environmental factors such as masticatory stress. Some authorities have suggested that the torus palatinus is inherited as an autosomal dominant trait. However, others believe that the development of this lesion is multifactorial, including both genetic and environmental influences.

Most palatal tori can be diagnosed clinically based on their characteristic appearance; therefore biopsy rarely is necessary. In edentulous patients, the torus may need to be removed surgically to accommodate a denture base. Surgical removal may also be indicated for palatal tori that become repeatedly ulcerated or that interfere with oral function.

TORUS MANDIBULARIS

The torus mandibularis is a common exostosis that develops along the lingual aspect of the mandible. As with torus palatinus, the cause of mandibular tori is probably multifactorial, including both genetic and environmental influences. Most mandibular tori are easily diagnosed clinically and no treatment is necessary. However, surgical removal may be required to accommodate a lower full or partial denture. (STYLOHYOID SYNDROME; CAROTID ARTERY SYNDROME):

The styloid process is a slender bony projection that originates from the inferior aspect of the , anterior and medial to the stylomastoid foramen. It is connected to the lesser cornu of the hyoid bone by the stylohyoid ligament. The external and internal carotid arteries lie on either side. Elongation of the styloid process or mineralization of the stylohyoid ligament complex may impingement or compression of adjacent nerves or blood vessels and caused Eagle syndrome

Treatment and Prognosis

Treatment of Eagle syndrome depends on the severity of the symptoms, for mild cases no treatment may be necessary (except reassurance of the patient). Local injection of sometimes provides relief. In more severe cases, partial surgical excision of the elongated styloid process or mineralized stylohyoid ligament is required.

STAFNE DEFECT: (STAFNE BONE CYST; UNGUAL MANDIBULAR SALIVARY GLAND DEPRESSION; LATENT BONE CYST; STATIC BONE CYST; STATIC BONE DEFECT; LINGUAL CORTICAL MANDIBULAR DEFECT)

Stafne described a series of asymptomatic radiolucent lesions located near the angle of the mandible. The classic presents as an asymptomatic radiolucency below the mandibular canal in the posterior mandible, between the molar teeth and the angle of the mandible the lesion is typically well circumscribed and has a sclerotic border. Sometimes the defect may interrupt the continuity of the inferior border of the mandible, with a palpable notch observed clinically in this area. Most Stafine defects are unilateral although bilateral cases may be seen. Although the defect is believed to be developmental in nature, it does not appear to be present from birth. Most cases have been reported in middle-aged and older adults.

Developmental cysts

A cyst is a pathologic cavity (often fluid filled) that is lined by epithelium. A number of different developmental cysts of the head and neck have been described. Some of these have been considered historically as "fissural" cysts because they were thought to arise from epithelium entrapped along embryonal lines of fusion. However, the concept of a fissural origin for many of these cysts has been questioned in more recent years. In many instances the exact pathogenesis of these lesions is still uncertain. Regardless of their origin, once cysts develop in the oral and maxillofacial region, they tend to slowly increase in size, possibly in response to a slightly elevated hydrostatic luminal pressure.

Nasopalatine duct cyst: an intaosseous developmental cyst of the midline of the anterior palate, derived from the island of epithelium remaining after closure of the embryonic nasopalatine duct. Arises from embryonic remnants of the nasopalatine duct. Most of these cysts develop in the midline of the anterior near the incisive foramen.

Radiographical features:

The present as a well-circumscribed oval or heart-shaped radiolucency located in the midline of the anterior maxilla between the roots of the central incisors. Although some of these cysts are asymptomatic and discovered during routine radiographic examination, many are inflamed and causes pain , pressure ,and swelling.

Histopathology

These cyst are lined by a layer of ciliated columnar (respiratory), cuboidal, or stratified squamous epithelium or by a mixture of these epithelial types. The cyst capsule typically exhibits the prominent component of blood vessels and peripheral nerves that comprise normal incisive canal contents.

Treatment:

Treatment of the nasopalatine duct cyst is by surgical enucleation , using a palatal approach. Recurrence of this cyst is rare.

Nasolabial cyst:

A developmental cyst of the soft tissue of the anterior mucobuccal fold beneath the ala of the nose, most likely derived from remnants of the inferior portion of the nasolacrimal duct.

Clinical and radiographical features:

This cyst is a unilateral or occasionally bilateral painless soft tissue swelling that result in a flattening of the naso-labial crease on the skin below the ala of the nose. If the upper lip is appropriately retracted, this cyst also can be seen inta-orally as a swelling located at the depth of the maxillary vestibule. Most of these cysts occur in the fourth and fifth decades of life and have a female predilection of approximately 3 to 1.

Because this cyst is located entirely within soft tissue, it is not readily apparent radiographically.

Histology:

The cyst is lined by a layer of pseudo stratified columnar epithelium exhibiting variable numbers of mucus (goblet) cells or by a ductal type of cuboidal epithelium. A lining of stratified squamous epithelium can be seen in some lesion.

Treatment:

A is treated by surgical enucleation with particular care being exercised to prevent the lesion's perforation and collapse. Lymphoepithelial cysts:

A cyst with a lumen lined by a keratinized stratified squamous epithelium and a capsule containing multiple normal lymphoid follicles and a dense accumulation of normal lymphocytes.

Lymphoepithelial cysts are relatively uncommon lesion that occurs in several areas of the head and neck, most commonly in the floor of the mouth and on the lateral aspect of the neck. Those occurring intraorally are termed oral lymphoepithelial cysts, and those occurring on the lateral aspect of the neck are termed cervical lymphoepithelial cysts.

Oral lymphoepithelial cyst

The oral lymphoepithelial cyst is most commonly found on the anterior floor of the mouth and on the posterior lateral borders of the tongue. It is a symptomatic, yellow or tan, superficial submucosal mass that usually measures less than 1 cm in diameter.

Histopathology

The cyst is lined by a relatively thin layer of parakeratinized squamous epithelium surrounded by a well-defined mass of normal lymphoid tissue exhibiting variable numbers of germinal centers.

Cervical lymphoepithelial cyst:

The cervical lymphoepithelial cyst, also commonly termed branchial cleft cyst or benign cystic lymph node, occurs on the lateral aspect of the neck, usually anterior to the sternocleidomastoid muscle. It is thought to be derived from epithelium entrapped with in lymphoid tissues of the neck during embryologic development of the cervical sinuses or the second branchial clefts or pouches.

Clinical features

The cyst becomes apparent in late childhood or early adulthood as a painless swelling on the lateral aspect of the neck anterior to the sternomastoid muscle. A draining fistula that communicates between the cyst and the overlying skin surface occasionally develops.

Thyroglossal tract cyst:

A cyst located above the thyroid gland and beneath the base of the tongue, with a lumen lined by a mixture of epithelial cell types derived from remnants of the embryonic thyroglossal tract and often containing thyroid tissue in the capsule.

The thyroglossal tract cyst is a relatively uncommon lesion derived from embryologic remnant of the thyroglossal tract. This tract extends from the foramen caecum on the middorsum of the tongue to the thyroid gland. Although these cysts can develop anywhere along the length of this tract,70% to 80% occur below the hyoid bone, where the tract makes two distinct turns on its descent to the thyroid gland.

Clinical features:

This cyst occurs primarily in children and young adults and presents as an asymptomatic, slowly enlarging, and mobile swelling involving the midline of the anterior neck above the thyroid gland. A small percentage of these cysts occur within the tongue, where they can cause dysphagia. If infected or inflamed a draining fistula that communicates between the cyst and the overlying skin surface will occasionally develop.

Histopathology:

This cyst is lined by stratified squamous epithelium, ciliated columnar epithelium, transitional epithelium, or a mixture of epithelium types. The cyst capsule can exhibit a number of additional findings including thyroid tissue mucus glands, and sebaceous glands.

Treatment: The treatment of the thyroglossal tract cyst requires complete surgical excision, because recurrence is a distinct possibility. In an effort to minimize recurrence of cysts involving the hyoid area, it is recommended that the central portion of the hyoid bone and its associated remnants of thyroglossal tract be removed.

Dermoid cyst: a cyst of the midline of the upper neck or the anterior floor of the mouth of young patients, derived from remnants of embryonic skin, consisting of a lumen lined by a keratinized stratified squamous epithelium, and containing one or more skin appendages such as hair, sweat, or sebaceous glands.

Clinical features:

The dermoid cyst is a lesion of young adults (teenagers).no gender predilection is seen. Cysts of the anterior upper neck or floor of the mouth present as painless swellings exhibiting a doughy consistency on palpation. Cysts that develop above the mylohyoid muscle present as a midline swelling in the sublingual (floor of the mouth) area. In this location the cyst results in elevation of the tongue and can interfere with eating and speaking. Cysts that develop below the mylohyoid muscle appear as a midline swelling in the submandibular and submental region.

Histopathology:

A layer of orthokeratinized squamous epithelium exhibiting variable number of dermal appendages, including hair follicle, sebaceous glands, and associated erector pili muscles lines the cyst. The cystic lumen is generally filled with a mixture of desquamated keratin, sebum, and hair shafts.

Treatment:

This cyst is best treated by surgical enucleation or excision. Recurrence is uncommon. Epidermoid cyst:

A cyst of skin with a lumen lined by keratinizing stratified squamous epithelium, usually filled with keratin and without skin appendages in the capsule wall.

The epidermoid cyst occurs primarily on skin. however, occasional cyst of the oral cavity exhibit the histopathologic characteristics of epidermoid cyst.

The epidermoid cyst closely resembles a dermois cyst, except that the former exhibit no dermal appendages.

GLOBULOMAXILLARY CYST:

The "" was purported to be a fissural cyst that arise from epithelium entrapped during fusion of the globular portion of the medial nasal process with the maxillary process. This concept has been questioned. However; because the globular portion of the medial nasal process is primarily united with the maxillary process and a fusion does not occur, therefore. Epithelial entrapment should not occur during embryologic development of this area. Current theory holds that most (if not all) cysts that develop in the globulomaxillary area are actually of odontogenic origin.

Clinical and Radiographic Features

The "globulomaxillary cyst" classically develops between the maxillary lateral incisor and cuspid teeth. A well-circumscribed unilocular radiolucency between and apical to the teeth because this radiolucency often is constricted as it extends down between the teeth. It may resemble an inverted pear. As the lesion expands, tipping of the tooth roots may occur. Treatment of cysts in the globulomaxillary area usually consists of surgical enucleation.