White patches and premalignant lesions of

oral mucosa Dr. Shahzadi Tayyaba Hashmi

DNT 243

INTRODUCTIONIn health the oral mucosa is pale pink, but

pathological changes may result in white patches

In many cases, this is brought about by changes in the keratinisation of the epithelium; for example, the cheeks are normally

non-keratinised but if epithelium become keratinised they will appear white clinically

There are many causes of white patches on the oral mucosa

1) FRICTIONAL KERATOSIS

Key features:White patches may occur in response to chronic

trauma and are known as frictional keratosisSites:Such lesions are common on the buccal mucosa in

a linear pattern adjacent to the teeth and this is known as occlusal line

They may also be seen on the tongue or other intraoral sites

Causes:Chronic bitingA sharp cuspAn over-extended dentureAn orthodontic appliance

FRICTIONAL KERATOSIS

Diagnosis: In order to make a diagnosis of frictional

keratosis the source of trauma must be identified and the position of the white patch should correspond to the trauma

Treatment: Treat the cause Surgically remove small discrete

lesions of more than 2 mm in

diameter Observe large lesions regularly

2) LICHEN PLANUS

Clinical features:Relatively common disorderMay affect the skin as well as the oral mucosaMiddle-aged women are affected more than

men In most cases, the disease is symptomlessHowever some patients may complain of

roughness or discomfort on eating spicy foods

LICHEN PLANUS PATTERNS

Typically, it is characterised by:1. Reticular, white interlacing lines or

striations which occur bilaterally on the buccal mucosa and tongue and occasionally the lips

2. White patches may be plaque-like rather than reticular or sometimes the mucosa appears Erythmatous and may show areas of erosion

3. Red lesions may show areas of ulceration4. Skin lesions may be present on the wrists and

appear as violet papules

Lichen planus

HISTOPATHOLOGYThe histological changes in lichen planus show

that the epithelium is keratinised, leading to the white striations seen clinically

In addition, there is a band of lymphocytes beneath the epithelium which is associated with destruction of the lower epithelial layers

TREATMENT

If there is no symptoms: no treatmentIf disease symptomatic: Corticosteroids

either topically or systemically

3) LEUKOPLAKIA

Etiology:Unknown causeThey are important lesions because a small

proportion have a higher risk of turning malignant (into developing squamous cell carcinoma)

Leukoplakia is therefore a premalignant lesion and identification of the high risk leukoplakias is important for the patient and dental care professional

TYPES OF LEUKOPLAKIA

The clinical appearance of Leukoplakia is very variable and they have been grouped into

a) Homogeneous Leukoplakiab) Non-homogeneous Leukoplakia

HOMOGENEOUS LEUKOPLAKIA

The lesions appear similar throughout and are usually flat, white patches, but some may have a regular undulating surface

This type of Leukoplakia has a negligible risk of turning malignant

NON-HOMOGENEOUS LEUKOPLAKIA

The lesions may show variations in the surface contour, they may be nodular or spiky

They may show variations in colour with red areas interspersed with white areas

It is within this group that the highest risk of malignant transformation occurs

High Risk areas of Leukoplakia

Lateral border of the tongueFloor of the mouthRetromolar areaThere is also an increased risk in patients who

take betel quid and in these patients Leukoplakia is found on the buccal mucosa