Tongue Diseases – Types, Causes Symptoms, Function

Types of Tongue Diseases

Congenital

Examples of congenital disorders which affect the tongue include:

• Aglossia – complete absence of the tongue at birth
• Ankyloglossia (tongue-tie) – where the lingual frenum tethers the tongue to the floor of the mouth. If it interferes with oral hygiene and feeding, a frenectomy may be indicated.
• Hypoglossia – congenitally short tongue
• Macroglossia
• Macroglossia – an abnormally large tongue, seen in some disorders such as Down syndrome? (although macroglossia can be an acquired condition? as well).
• Hamartomata – for example, Leiomyomatous hamartoma
• Glossoptosis
• Choristomata – For example, osseous choristoma of the tongue, a very rare condition characterized by a nodule? on the dorsum of the tongue containing mature lamellar bone without osteoblastic or osteoclastic activity.^[rx] Cartilaginous (chondroid),^[rx] and glial choristomas may also very rarely occur on the tongue.^[rx]
• Lingual thyroid?
• Cleft tongue (bifid tongue) – completely cleft tongue is a rare condition caused by a failure of the lateral lingual swellings to merge.^[rx] More common is an incompletely cleft tongue, appearing as midline fissure. This is normally classed as a fissured tongue.

Acquired

Vascular

• Caviar tongue – the veins? underneath the tongue can become dilated and prominent, giving the undersurface of the tongue a caviar-like appearance.
• Hemangioma

Infective

• Glossitis – some types of glossitis are caused by infections, e.g. median rhomboid glossitis (Candida species), “strawberry tongue” (seen in scarlet fever?), and syphilitic glossitis (seen in tertiary syphilis).
• Oral hairy leukoplakia (seen in people with immunosuppression, caused by Epstein–Barr virus)
• Oral candidiasis can affect the tongue. Risk factors for oral candidiasis include antibiotic? and corticosteroid use, and immunodeficiency (e.g. HIV),^[rx] or diabetes mellitus?).

Traumatic

• The tongue may be traumatized by mechanical, thermal, electrical, or chemical means. A common scenario is where the tongue is bitten accidentally whilst a local anesthetic inferior alveolar nerve block is wearing off. The tongue may develop scalloping on the lateral margins, sometimes termed crenated tongue. This appearance is the result of indentations of the teeth where the tongue is habitually pressed against the teeth (“tongue thrusting”, and example of oral parafunction). A lesion? similar to morsicatio buccarum can occur on the tongue (sometimes called morsicatio linguarum), caused by chronic? chewing on the tongue. The ventral surface (undersurface) of the tongue may also be traumatized during oral sexual activity such as cunnilingus (“cunnilingus tongue”).^[rx]

Autoimmune?

• Autoimmune conditions such as Sjögren syndrome can cause xerostomia, with resultant glossitis.

Inflammatory

• Glossitis
• Oral lichen planus

Neurological

• Hypoglossal nerve weakness? can cause atrophy? and fasciculation of the tongue.
• Melkersson–Rosenthal syndrome – a neurological disorder characterized by fissured tongue, facial palsy and orofacial swelling?.

Neoplastic

• The sides (lateral) and undersurface (ventral) of the tongue are high risk sites for the development of oral cancer, most commonly squamous cell carcinoma?.

Degenerative

• Motor neuron disease (Lou Gehrig’s disease) can cause impaired control of tongue movement, affecting speech and swallowing.

Environmental

• Poor diet can cause malnutrition and nutritional deficiencies. Deficiency of iron, B vitamins and folic acid are common causes for atrophic glossitis.
• Black hairy tongue – some factors thought to cause black hairy tongue are environmental, such as eating a soft diet, poor oral hygiene, smoking and antibiotic use.

Unknown

• Geographic tongue (benign migratory glossitis) – a common disorder that occasionally causes a burning sensation but is usually painless. Irregular patches of depopulation form on the tongue giving the appearance of a map. The cause is unknown.
• Leukoplakia – can affect the tongue
• Tongue coating – food debris, desquamated epithelial cells and bacteria often form a visible tongue coating.^[rx] This coating has been identified as a major contributing factor in bad breath (halitosis),^[rx] which can be managed by brushing the tongue gently with a toothbrush or using special oral hygiene instruments such as tongue scrapers or mouth brushes.^[rx]
• Burning mouth syndrome – this chronic pain? disorder commonly involves the tongue. In reflection of this, some of the synonyms for the condition include tongue-specific terms such as “glossodynia” or “burning tongue syndrome”. Burning mouth syndrome is characterized by a chronic burning sensation on the tongue and other oral mucous membranes in the absences of any identifiable signs or causes.

Iatrogenic

• Paratrichosis tongue – Real hair implanted on the tongue.

The Function and Tongue Diseases

The tongue participates in a variety of functions such as taste, speech, and food manipulation and cleaning of the oral cavity.

Taste Functions

The dorsal surface of the tongue is covered by a stratified squamous epithelium, with numerous papillae such as circumvallate papilla, fungiform papilla, filiform papilla, and foliate papilla. Taste buds which are intraepithelial chemosensory organs present within these papillae are responsible for taste perception. The circumvallate papilla carries the maximum number of taste buds. These taste buds via gustatory cell receptors interact with the chemicals present in the food and induce different taste sensations (sweet, salty, sour, and bitter).

Speech Functions

Various speech sounds require the interaction of the tongue with the teeth and different parts of the palate. The linguodental sounds such as “Th” require interaction between the tip of the tongue with the incisal surface of upper and lower incisors. The linguopalatal sounds may include the contact of the tongue with the anterior or the posterior part of the hard palate. When the tip of the tongue contacts with the anterior part of the hard palate, sounds such as “D, T, N, and, Z” is produced. When the tongue forms a valve and contacts the posterior part of the hard palate, it produces sounds like “ch” and “sh.” The velar sounds include a contact of the posterior part of the tongue with the soft palate. these sounds include “k” and “g .”

Food Manipulation Functions

The tongue aids in moving the food onto the occlusal surface of the teeth, mixing it with saliva as the food move away from the teeth, and in placing the food again on the teeth.[rx] Thus, it helps in the formation of food bolus during the oral phase of deglutition. It also helps in propelling the food bolus beyond the anterior tonsillar pillar, which triggers the swallowing reflex.

Others Disease condition of Tongue diseases

Aglossia – Congenital absence of the tongue is extremely rare. Usually, the tongue is absent in cases of gross underdevelopment or maldevelopment of the first visceral arches.

Macroglossia – It is an uncommon developmental condition and is also known as hypoglossia. Its defining feature is a rudimentary or an abnormally small tongue. It leads to limited muscular movement and is associated with syndromes such as Hanhart syndrome.

Macroglossia – Macroglossia is an infrequently encountered condition characterized by tongue enlargement, seen in association with other congenital defects leading to syndromes such as down syndrome (trisomy 21), Beckwith-Wiedemann syndrome.

Ankyloglossia – It occurs due to failure in cellular degeneration leading to a longer anchorage between the tongue and floor of the mouth; this is commonly known as “tongue-tied” and demonstrates an abnormally short lingual frenulum. Ankyloglossia can range in severity from mild? to complete ankyloglossia in which the tongue gets fused to the floor of the mouth restricting its free movement.[rx] A short lingual frenulum leading to tongue-tie is also associated with several genetic? syndromes such as related Robinow syndrome, oral-facial-digital syndrome Type I, Opitz syndrome, and Van der Woude syndrome.

Cleft tongue – It is also known as bifid tongue and occurs when the lateral swellings fail to merge. It can be partial or complete. The former is a more common entity and is manifested as a deep groove on the dorsal surface of the tongue in the midline. It occurs when the mesenchymal proliferation interferes with the merging leading to failure of the obliteration of the groove. There are reports of bifid tongue in syndromic cases like Opitz G BBB syndrome, oral-facial-digital syndrome type I, Klippel–Feil anomaly, and Larsen syndrome.[rx]

Pentafid tongue – Disturbance in the mesodermal penetration and mesenchymal fusion during the development of tongue development is responsible for this malformation.

Fissured tongue – It is also known as scrotal tongue or lingua fissurata. It is congenital anomaly? manifested as grooves oriented anteroposteriorly on the dorsal aspect of the tongue with multiple branches extending towards the lateral aspect. The grooves range from 2 to 6 mm in depth. In a severe? form of the fissured tongue, when the grooves are extremely prominent and interconnected, the tongue may appear to be lobulated. It can also present in association with down syndrome or Melkerson-Rosenthal syndrome (a triad of the fissure, granulomatous cheilitis, and cranial nerve VII paralysis?).

Geographic tongue – Geographic tongue, also known as lingua geographica or benign migratory glossitis is an inflammatory disorder caused by loss of filiform papillae.

Hairy tongue – It is also known as a black hairy tongue and characteristically demonstrates the accumulation of excess keratin on the filiform papillae on the dorsal surface of the tongue leading to the formation of elongated strands resembling hair. This condition most commonly affects the midline just anterior to the circumvallate papillae, usually sparing the lateral and anterior borders.

Median rhomboid glossitis – It is a condition that presents in the midline of the dorsal surface of the tongue, just in front of the circumvallate papillae. It presents as a well-demarcated, symmetric, depopulated area. However, it also occasionally appears in the paramedical location.

References