Dr. Saleem Shaikh

Oral mucosa is lined by stratified squamous epithelium, which is further of two types - keratinized and non keratinized. Due to some stimulus like friction, infection, chemicals etc some of these non keratinized areas may get keratinized or in some cases the keratinized areas become hyperkeratinized. When normally nonkeratinized tissue turns into keratinized it is known as ‘keratosis’ Such lesions are known as ‘Keratotic lesions’.

 This group involves a number of various lesions and most of them commonly present as white coloured lesions, Due to excess of keratin production. Leukoplakia Lichen planus White sponge nevus Keratoacanthoma Hairy tongue Linea alba Smoker’s palate Verrucous carcinoma Oral hairy leukoplakia Hyperplastic candidiasis

 (leuko = white; plakia = patch)  is the most common potentially malignant lesion of the oral mucosa.  “a predominently white non scrappable plaque or patch of the oral mucosa that cannot be characterised as any other definable lesion”.  Etiology: tobacco is the most important etiology, both smoking and smokeless forms of tobacco can cause leukoplakia. Sometimes leukoplakia is also seen in non tobacco users, i.e. without any known causative factor such cases have been referred to as ‘Idiopathic leukoplakia’.

 Clinical features: It is seen usually unilaterally on the buccal mucosa or the vestibule or any other part of the oral mucosa where tobacco is placed for chewing. It appears as a white patch which cannot be scrapped (wiped) off with a gauze piece or spatula. Based on its appearance it can be further classified into  Homogenous: when it is uniformly white in colour  Non Homogenous: when it is mixed with red areas such lesions are also referred as speckeled leukoplakia, nodular leukoplakia or erythroleukoplakia.

 Usually non homogenous variant have poor prognosis and are associated with pain and discomfort as compared to the homogenous variant.   Proliferative verrucous leukoplakia (PVL) is an aggressive variant of leukoplakia, which clinically presents as a fingerlike warty lesion and invariably progresses onto malignancy.

 Histological features: Histologic features of this lesion are not specific, hyperkeratosis and epithelial hyperplasia are typically seen. Dysplasia ranging from mild to severe is also seen in 10-20% of the cases.  Leukoplakia is a clinical diagnosis and histology is used to only rule out other definable lesions. Hence it is also said that it is a negative diagnosis.  Treatment: If it is a small patch and is not causing any problem then ask the patient to stop tobacco use and put him under observation. If it is otherwise or shows dysplastic features than excision is the treatment of choice.

 Hairy tongue caused by defective desquamation of the filiform papillae, due to various factors.  Etiology: hypertrophy of filliform papillae due to lack of mechanical friction.  It is usually seen in individuals with poor oral hygiene (eg, lack of tooth brushing), eating a soft diet, chronically ill patients etc.  Although it should be white due to excess keratin, hairy tongue usually is black in color or of any other color depending on the diet.

 Clinical features: filliform papillae which are usually 1mm in size may extend upto 15 mm, this causes tickling sensation on the soft palate, Gagging and Halitosis  Treatment: use of a simple tongue cleaner is sufficient to remove the excess keratin, in severe cases scissors or lasers can be used. Prognosis is excellent.

 This is a hereditary condition which is inherited by autosomal pattern  it does not appear at birth it is gradually noticed around 9-10 yrs and by yrs is at its peak.  Oral lesions are widespread seen on the cheeks, palate, floor of the mouth etc. mucosa appears thick sponge like and corrugated and is of white color.  It is asymptomatic and only complaint here is the aesthetics and the patient may be uncomfortable due to thick mucosa

 Histologic features: Hyperkeratosis and acanthosis, Intracellular edema with perinuclear orange bands are also seen.  Treatment: usually no treatment if asymptomatic, but if excised prognosis is excellent.

 (Leukokeratosis nicotina palate) this is a lesion seen on the palate of smokers; specially pipe, cigar and beedi smokers.  Clinical features: the lesion is seen on Hard palate as a reaction to heat due to smoking. Palate shows a grayish white coating which is due to hyperkeratosis and tiny red spots are also noticed these are the inflamed orifices of the minor salivary gland ducts.  Reverse smokers palate – this is a condition resulting from a peculiar habit of keeping the lighted end of the cigarette in the oral cavity. The resulting lesion looks similar to smokers palate but it usually is premalignant in nature.

 Histologic features: hyperkeratosis of the epithelium and melanin deposits and inflammatory cells in the laminapropria are seen. Reverse smokers palate also shows dysplastic features in the epithelium.

 Hairy leukoplakia is a white patch on the side of the tongue with a corrugated or hairy appearance.  This condition is seen commonly as an oral manifestation of HIV infection and considered by many clinicians as an oral marker for AIDS.  Etiology: It results from an opportunistic infection by Epstein Barr virus (EBV) and Human Pappiloma virus (HPV)

 Clinical features: Patients with oral hairy leukoplakia may report a nonpainful white plaque along the lateral tongue borders.  Lesions may frequently appear and disappear spontaneously.  Hairy leukoplakia is often asymptomatic, some patients with hairy leukoplakia do experience symptoms including mild pain, alteration of taste.  Size ranges from small lesions to irregular "hairy" or "feathery" lesions with prominent folds or projections.  Treatment: Usually subsides in its own as the immunity is restored and does not increase in size rapidly hence no specific treatment is required. However for large lesions antiviral medications such as acyclovir can be administered.

 Oral lichen planus (OLP) is a common mucocutaneous disease.  bilateral white striations, papules, or plaques on the buccal mucosa, tongue, and gingivae. Erythema, erosions, and blisters may or may not be present.  oral involvement is almost always seen sometimes even without skin lesions.  Etiology: oral lichen planus is a T-cell–mediated autoimmune disease

 lichen planus antigen may be induced by drugs (lichenoid drug reaction), contact allergens in dental restorative materials or toothpastes (contact hypersensitivity reaction) mechanical trauma (Koebner phenomenon), viral infection, or unidentified agents. It is interesting to note that the disease seldom is seen in carefree persons; the nervous, high- strung person is almost invariably the one in whom the condition develops.

 lichen planus, diabetes mellitus and vascular hypertension - the triad being described as Grinspan’s syndrome.  the lesions are characterized by lesions consisting of radiating white or gray, velvety, threadlike reticular patches, rings and streaks

 Depending on the predominant clinical pattern oral lesions are classified into Reticular Erosive Hypertrophic / Plaque Papular Atrophic Vessiculo bullous  Reticular pattern is the most common pattern and atropic and erosive pattern are more likely to be symptomatic and may turn malignant.

 Histologic Features:  hyperparakeratosis or hyperorthokeratosis  acanthosis with intracellular edema  a “saw tooth” appearance of the rete pegs.  Band like subepithelial mononuclear infiltrate consisting of T cells  degenerating basal keratinocytes that form colloid (Civatte, hyaline, cytoid) bodies, . histologic clefts (ie, Max-Joseph spaces) may be seen between the basal layer and basement membrane.

 Treatment: Due to its minimal potential for malignant transformation, these patients need to be kept on long- term follow up.  Medical treatment of OLP is essential for the management of painful, erythematous, erosive, or bullous lesions. The principal aims of current OLP therapy are the resolution of painful symptoms, the resolution of oral mucosal lesions, the reduction of the risk of oral cancer, and the maintenance of good oral hygiene. As it is an autoimmune mediated condition corticosteroids are recommended.

Linea alba literally means ‘white line’.  It is used to describe a horizontal streak on the inner surface of the cheek, level with the biting plane.  It usually extends from the commissure to the posterior teeth. likely associated with pressure, frictional irritation, or sucking trauma from the facial surfaces of the teeth.  May be also seen when the posterior over jet is insufficient.

 It is a low grade variant of squamous cell carcinoma  It differs in its clinical appearance, peculiar Histologic features and its clinical behavior.  The lesions commonly have rugaelike folds with deep clefts between them,  it is exophytic and appears to be fixed to the underlying structures.  Usually asymptomatic when it is small the patient reports to the clinic because of the exophytic nature of the growth.

 Histologic features: histologically these lesions appear orderly and harmless,  the epithelium is well differentiated and shows very less dysplastic features,  it is hyperplastic and grows downwards into the connective tissue without break in the basement membrane.  Typically cleftlike spaces filled with parakeratin are seen, this is known as parakeratin plugging.  The parakeratin lining the clefts with the parakeratin plugging is the hallmark of verrucous carcinoma.  Chronic inflammatory cells are seen in the connectivetissue.