Oral Pathology for Doctors

This  overview of oral diseases is taken from the Oral Diseases module of the Dermatology Diploma course for General Practitioners provided through the  Australian Institute of Dermatology.

When examining the skin you should always remember to look in the mouth. It can give you a lot of relevant information ranging from the state of the teeth to the condition of the tongue re nutrition and the oral manifestations of many systemic diseases but particularly lichen planus.

 NSAIDS • Antihypertensives • Hypoglycaemics • Others More often cause ulcerative LP

Lichen planus typically gives a reticulate pattern white network on the buccal mucosal surfaces opposite the back molars. It can also give ulceration in the mouth and of course the differentials when ulceration occurs are pemphigus, erythema multiforme or a fixed drug reaction.

  Dermnet on oral lichen planus

 Apthous Ulcers They can be single or multiple. Most cases are just one or two at a time. You can have a giant aphthous ulcer called a Sutton's ulcer. Multiple aphthous ulcers can be associated with Vitamin B12, foliate and iron deficiency and you should always check the blood for these haematinic deficiencies in any patient with recurrent aphthous ulcers. They should avoid any sharp foods such as potato crisps and avoid biting or traumatising the inside of the mouth

Dermnet on Apthous ulcers

Lichen planus on the buccal mucosa

Apthous ulcers take several forms.

These are some of the oral variants of lichen planus

Oral Infections

Candidiasis 
Acute – Pseudomembranous – Erythematous (antibiotic stomatitis) •
Chronic – Erythematous (denture stomatitis) – Hyperplastic (candidal leukoplakia) – Median rhomboid glosssitis – Angular cheilitis •
Mucocutaneous

 The typical candida infection on the inside of the mouth is a white membrane usually on the tongue or buccal surfaces that can be wiped away quite easily. However there are more unusual presentations of candidiasis. You can get denture candidiasis where it presents as a punctate red erythematous area underneath the denture particularly over the hard palate. You can also get a median rhomboid glossitis. This is an atrophic area on the centre of the tongue towards the posterior third that looks glazed. Angular cheilitis is another presentation of candidiasis of the mouth. It is usually due to a loss of the gums with aging and fluid accumulating at the angles of the mouth. Sometimes you can have associated staph infection as well. Bactroban cream is a good treatment that will treat both possibilities. Mucocutaneous candidiasis is a very florid form of candidiasis seen in immunosuppressed patients where the lips as well as the inside of the mouth in all areas can be involved. Chronic mucocutaneous candidiasis as well as having oral involvement will have involvement of the nails and often vulval involvement in females.

  Dermnet on Oral Candidiasis

  Herpes simplex and Zoster Hand Foot and Mouth disease
Herpes simplex and hand foot and mouth diseases and herpangina. Herpangina is very painful and tends to affect the soft palate, the uvular and the anterior pillars of the tonsils. Herpes simplex tends to affect the lips but can affect the buccal mucosa. Hand foot and mouth disease again is mainly on the tongue and buccal surfaces. Herpes zoster in the mouth is unusual. It is part of the Ramsay Hunt syndrome and usually involves the glossa pharyngeal or ninth cranial nerve and it is the posterior pharynx and the posterior third of the tongue and one side.

The white stuck on patches of candidiasis.

Palatal hyperplasia from candida Image courtesy of Dr Thomas Koeck

Oral Crohn's disease Oral Crohn's is a rare disorder. It can be seen as an angular cheilitis but there is thickening of the rhagades at the angle of the mouth. Crohn's can also present with a cobblestoning and thickening of the buccal mucosa on the inside of the mouth or over the hard palate and the third presentation is as thickening of the lips both upper and lower as a granulomatous cheilitis. This is not a common presentation.

Buccal nodular infiltrate in Crohns disease

Cobblestone pattern of granulomatous infiltrate in Crohns disease.

Cheilitis granulomatosis of the lip

Oral pigmentation Pigmentation on the lips especially with multiple freckles can be a feature of the Peutz-Jeghers syndrome. Marked pigmentation of the gums can be seen with silver ingestion.also marked pigmentation of the mouth particularly on the buccal surfaces can be a feature of Addison's disease but these patients will usually have increased pigmentation of the palmar creases and evidence of increased facial pigmentation. Some buccal pigmentation is normal in certain races particularly Negroes and Aboriginals.

Always check the palmar creases for pigmentation

Leukoplakia.
  Leukoplakia represents hyperplasia of the mucous lining. It then absorbs water and becomes white. Not all leukoplakia is pre malignant. Some leukoplakia is just hyperplasia because of chronic irritation. However it is always important to biopsy an area of leukoplakia to see the degree of atypia of the keratinocytes or the squamous cells of the mucosal lining. If there is significant atypia then there is a risk that invasive SCC will develop.

 Erythroplakia is actually a more serious manifestation of changes to the lining of the inside of the mouth. It is much more likely to form an oral cancer. These areas should certainly be biopsied in several areas to see the degree of change. If there is any thickening of the underlying oral mucosa then this is more worrying. Usually these patients have bad teeth, poor oral hygiene or may be cigarette smokers. Oral cancer can be a very serious problem and it is certainly in Aboriginal communities particularly in Northern Queensland. People who chew betel nuts are also more likely to develop oral cancer. Local spread to the bones and local lymph nodes is not uncommon. Oral tumours are particularly seen in cigarette smokers and people with very poor hygiene. They can present as an ulcer with thickening and induration of the base or as a swelling.
Any swelling of the inside of the mouth with a rough verrucous surface should always be biopsied. Squamous cell carcinoma of the mouth is a particularly severe problem.

  Dermnet on Leukoplakia

Oral Tumours

 Kaposis Sarcoma • Endothelial tumour • Co-infected with Human Herpes 8 • Majority affect head and neck region • Non-aggressive.

Other tumours that may occur in the mouth include non Hodgkins lymphoma presenting as a large peri tonsillar mass or Kaposi's sarcoma presenting as a bruise or a vascular like area either on the hard palate and gum surfaces or on the buccal mucosa. Again these were much more common in HIV patients before the onset of HAART therapy but are now much less common. They were due to Herpes virus 8 infection

  Dermnet on Oral Cancers

Kaposis sarcoma commonly presents in the mouth in HIV patients.

SCC in the mouth can arise denovo or secondary to chronic oral disease such as lichen planus

Non Hodgkins lymphoma may present as a posterior palatine tonsillar swelling like this.

Benign Oral Tumours They present as a smooth surfaced swelling particularly on the anterior buccal mucosa usually in the line of the bite line or sometimes on the tongue. They are the result of injury and sometimes chronic irritation trauma to the area. These oral fibromas can be left. They usually persist but are seldom a problem to the patient. If they are a problem and there is a tendency to continually irritate or bite them then they should be excised.

  Dermnet on Oral Fibromas

Tongue Disorders The red glazed tongue can be a feature of vitamin B deficiency and should particularly be looked at in suspected alcoholics. It will reverse quickly with some thiamine. A painful glazed tongue can also be a feature of an antibiotic induced candidiasis and the area should always be swabbed.

 Glossitis with a red glazed tongue can also occur in iron deficiency as in the example below.

 The commonest problem you will see with the tongue that patients will present with is geographic tongue. This is a curious migrating anular loss of the papillae on the surface of the tongue but generally is asymptomatic. It is thought by some people to be a form of oral psoriasis but we really do not know what the cause is and it does not require treatment.

 Thickening of the papillae of the tongue can occur particularly in chronic smokers. Note that the circumvallate papillae at the back of the tongue are a normal variant and do not represent any type of tumour.

 Other tongue disorders include oral hairy leukoplakia where there is a thick adherent white membrane generally at the sides of the tongue seen particularly in HIV patients. It is due to the Epstein Barr virus infection along with other associated bacteria.

  This is an excellent lecture on Tongue disorders lasting about 25 mins with excellent images. Slowish start but it soon warms up.

A white sponge nevus present from birth.