Oral mucosa Flashcards
What are the different parts of tissue that you can see histologically?
There is the epithelium which may be stratified squamous. This is divided into the basal cell layer, prickle cell layer and granular layer which produces keratin. Beneath the epithelium there is the the connective tissue consisting of the lamina propria which is the superficial part and submucosa which contains fat. Beneath this there is muscle.
What are the types of keratinised epithelium?
There is orthokeratinised which has no nuclei and parakeratinised which has nuclei.
What are the types of mucosa in the mouth?
The gingiva and hard palate is masticatory mucosa. The uvula, soft palate, floor of mouth and buccal mucosa is lining mucosa. The tongue is gustatory mucosa or specialised mucosa. There is a junction between the lining and masticatory mucosa called the mucogingival junction.
Why are palatal injections more painful?
The palate doesn’t have a submucosa and is firmly fixed to the underlying bone and is called mucoperiosteum. It resists the stresses and strains of eating and mastication. During palatal injections there is little space for anaesthetic to diffuse anywhere. Whereas lining mucosa has a loose submucosa for movement.
What does specialised mucosa on the tongue consist of?
It is found on the dorsum of the tongue. There are 4 types of papillae which are filiform, fungiform, foliate and circumvallate. Filiform is the most common papillae on the tongue. Fungiform are found all over the tongue. Circumvallate papillae are found on the posterior border of the tongue. Foliate are found on the lateral border of the tongue. They can get caught on the molars and become hyperplastic. All the papillae are for taste buds except for filiform which are for abrasion.
What are the 3 common variations on normal mucosa?
- Leukoedema
- Geographic tongue
- Fordyce spots
What is Leukoedema?
It is a variation on normal which is common in African-Americans. There are milky white areas often seen bilaterally on buccal mucosa. It has a classic appearance and if you stretch the cheek it will disappear.
Histologically there is oedema in the epithelium.
What might the differential diagnoses be for leukoedema?
- Lichen planus (sore, lacey white lines)
- White sponge naevus (hereditary, patches are thicker)
- Frictional keratosis (chronic cheek biting)
What is geographic tongue and the treatment?
It is also called erythema migrans and there are islands of red erythema with white halos/borders around them which move around the tongue and varies day to day. It affects the dorsal tongue, sometimes the lingual side but this is less common. It is usually asymptomatic but can become symptomatic with mild soreness due to spicy foods or aggravating factors. It is common. Patients should avoid spicy or acidic foods e.g. tomatoes. Difflam mouthwash can be prescribed.
What might the differential diagnoses be for geographic tongue?
- Lichen planus
- Frictional keratosis
What are fordyce spots?
They are ectopic sebaceous glands which appear as white or yellow speckling. It is common, easily diagnosed and asymptomatic.
What is white sponge naevus?
It is a hereditary condition which is autosomal dominant and a point mutation in keratin 4 or 13 genes. There will be a family history but it may skip generations. it it bilateral and seen on cheeks and the floor of the mouth. it appears as thick white folds which are wrinkled and ebbing tide. It is lifelong and may affect other mucosa sites also. The floor of mouth is a common site for dysplasia and SCC so refer if seen.
How does white sponge naevus appear histologically?
The epithelium is thickened and hyperplastic. The prickle cell layer is increased and there is lots of keratin on the surface. There is no inflammatory component or dysplasia.
What are the differential diagnoses for white sponge naevus?
- Lichen planus (burning sensation with acidic/spicy foods)
- Lichenoid drug reactions (usually have reddening and not from childhood)
- Frictional keratosis
- Leukoedema
How can the oral mucosa change with age?
- Mucosa may appear atrophic and smoother
- Decrease in elasticity
- Prominence of fordyce spots
- Varicosities - ventral surface of tongue (prominent veins)
What are the types of trauma in the oral mucosa?
- Mechanical - from dentures, teeth, orthodontic appliances, surgical wounds
- Chemical - burns e.g. aspirin, allergic response to dental materials
- Physical - extremes of hot and cold, irradiation
There will be epithelial changes and connective tissue changes in trauma.
What are the causes of traumatic ulceration?
- Trauma from dentures
- Teeth
- Chemical burns
- Irradiation for malignancy
How does an ulcer appear histologically?
It is complete loss of the epithelium. There is a pinker band on top which is fibrinopurulent slough. Underneath there is granulation tissue which is endothelial cells forming new blood vessels and fibroblasts forming collagen.
How can the epithelium respond to trauma?
It can ulcerate. It can produce more keratin to protect itself. If non-keratinised mucosa becomes keratinised this is called keratosis. If keratinised mucosa produces more keratin this is hyperkeratosis. Another change is hyperplasia of the epithelium or atrophy where it becomes thinner. Atrophy is a reduction in the thickness of the epithelium due to a loss of cells.
What are the connective tissue changes in trauma?
There can be hyperplasia which is overgrowth of the connective tissue and this produces a fibrous polyp. Polyps can vary in how they look. They may be seen on the anterior palate due to deep/traumatic overbite. They can be seen on the ridges due to denture trauma.
What are some specific examples of trauma affecting the oral mucosa?
- Frictional keratosis
- Stomatitis nicotina
- Papillary hyperplasia of the palate
- Chemical burns
What is frictional keratosis?
It is a white patch caused by continuous trauma and usually seen along the occlusal line or opposite sharp cusps, orthodontic wires or dentures. Histologically you would see hyperkeratosis, acanthosis and no inflammation or dysplasia.
What is the management of frictional keratosis?
You must be able to demonstrate the lesion is caused by trauma. If you remove the cause then the lesion should regress. If not then consider other white lesions in differential diagnosis. Leukoplakia is a white patch of unknown cause and there is increased risk of malignant change so this is important to note. The management is incisional biopsy to establish diagnosis.
What is stomatitis nicotina and the treatment?
It is seen on the palate in pipe and cigar smokers. It is a response to chronic heat. It is not a pre-malignant condition and there is a positive correlation between intensity of smoking and severity. The treatment is to stop or reduce smoking and the lesions may disappear. It should be regularly reviewed.
What is papillary hyperplasia of the palate?
It is caused by ill-fitting dentures and is symptomless erythematous overgrowth of the mucosa. It corresponds to the outline of the denture. The management is provision of new dentures. There can be excision of papillary projections for advanced cases. It is not a pre-malignant lesion.
What factors affect healing?
- Primary or secondary intention (wounds closely opposed heal faster than those separated)
- Foreign body - acts as a focus of infection and delays healing (e.g. bone, root - there will be neutrophils around it and form an abscess containing puss, there may also be osteoclasts to remove bone - open up wound and remove)
- Vascular supply (reduced blood supply reduces healing capacity)
- Nutritional deficiencies (vitamin C)
- Irradiation (reduces blood supply)
- Malignancy (failure to heal e.g. non-healing tooth socket)
- Infection (reduces healing capacity)
- Poor immune response (Leukaemia, diabetes, immunosuppression)
What is primary and secondary intention?
Primary intention is when the edges of a wound are brought together. It is used for incisional biopsy and a big biopsy will heal just as quickly as a small one. Secondary intention is for a gingivectomy or tooth extraction socket.
Refer ulcer on pathway after 3 weeks.
What are the types of localised gingival swellings?
- Fibrous hyperplasia (fibroepithelial polyp)
- Pyogenic granuloma
- Peripheral giant cell granuloma
- Gingival cyst
- Bohn’s nodules (and epstein pearls - dots along midline of palate, disappear on own)
(top three are most important)
What are the types of generalised gingival swellings?
- Inflammatory - chronic hyperplastic gingivitis
- Hereditary - gingival fibromatosis
- Neoplastic -leukaemia infiltration
- Hormonal - endocrine related (puberty, pregnancy)
- Diet related - scurvy
- Associated with GI tract disease - crohn’s disease
- Drug related - drug induced hyperplasia
What is a fibroepithelial polyp?
They are caused by an overgrowth of fibrous connective tissue and covered by hyperkeratinised stratified squamous epithelium. They can be pedunculated or sessile and are the same colour as the oral mucosa. It is a firm nodule which is painless unless traumatised. It is caused by trauma (dentures, teeth, orthodontic appliances). They are common on the cheeks, tongue and lip. The treatment is to excise and remove the cause, then send for histopathological examination.
What is a pyogenic granuloma?
It is a red/blue/purple vascular growth which grows rapidly. it can be sessile or pedunculated and is soft and bleeds easily. It is usually seen in age less than 40. It is common in pregnancy/puberty (pregnancy epulis). It is caused by trauma (plaque, calculus, dentures, teeth, orthodontic appliance). In pregnancy/puberty there is a hormonal induced exuberant response to the above. There is overgrowth of very vascular granulation tissue (endothelial cells and fibroblasts) which explains the red colour seen clinically. The top is always ulcerated which is why it appears red. There is fibrin on the top.
How is a pyogenic granuloma managed?
You should excise and remove the cause. In pregnancy give OHI and excise, however it may recur whilst the patient is pregnant. They can mature into fibroepithelial polyps.
What is a peripheral giant cell granuloma?
It is a soft red/blue sessile or pedunculated swelling consisting of vascular fibrous tissue. It usually occurs around anterior teeth and is seen more commonly in the mandible. The average age is less than 40. It is similar to a pyogenic granuloma clinically and can cause superficial bone resorption. It is only found on the gingiva. Histologically there are numerous multinucleate cells and haemorrhage. The histological diagnosis is based on a giant cell lesion but it is the same as giant cell lesions arising in bone e.g. central giant cell granuloma and hyperparathyroidism.
How is a peripheral giant cell granuloma managed?
It is important to determine whether the lesion has arisen in the gingiva or within bone and burst through the cortical plate. Take radiographs to check this. If it has arisen in bone the differential diagnoses include central giant cell granuloma and hyperparathyroidism (more common in 60+). Blood tests are used to check this.
Excise peripheral giant cell granuloma and curettage underlying bone to prevent recurrence. Send lesion for histopathological examination.
What are differential diagnoses for epulides?
- Firm mucosa coloured - fibroepithelial polyp
- Soft red, red/blue - pyogenic granuloma, giant cell granuloma
- If patient pregnant/puberty - more likely to be pyogenic granuloma
- Definitive diagnosis by excisional biopsy
- Exclude abscesses - red/yellow/soft/fluctuant, special investigations are vitality tests, radiography
What is gingival fibromatosis?
It is hereditary (autosomal dominant) and lifelong. There is pale pink, firm overgrowth which may cover and submerge the teeth. It may regrow after removal.
What is chronic hyperplastic gingivitis?
It is associated with poor oral hygiene and there is erythematous, hyperplastic gingiva which bleed on probing.
What is hormonal related gingival hyperplasia?
It is related to puberty and pregnancy and there is an exuberant response to plaque. The gingiva are red, erythematous and bleed easily on probing. You should disclose plaque and give OHI.
How does diet affect the gingiva?
There can be gingival hyperplasia in scurvy. It is caused by a diet poor in vitamin C and therefore failure to synthesis collagen. It is an inflammatory type hyperplasia which can lead to loss of teeth. It is very rare in the UK.
What is gingival hyperplasia associated with leukaemia?
There will be red, swollen gingivae which may exude pus and be ulcerated. It is in response to an excess amount of plaque. It may be associated with petechial haemorrhages, tiredness so look out for fatigue and easy bruising.
What is drug induced gingival hyperplasia?
It is associated with certain drugs such as cyclosporin (immunosuppressant), nifedipine (anti-hypertensive) and phenytoin (anti-convulsant). The gingivae are pale with a lobulated surface and little inflammation. Histologically you will see dense fibrous tissue, little inflammation and long epithelial rete ridges. The management is surgical reduction, improve oral hygiene and change drug regime if possible.
What is Crohn’s related gingival hyperplasia?
There may be labial swelling, aphthous ulcers, mucosal tags and cobblestoning.
What may the differential diagnoses be for generalised gingival hyperplasia?
- Pale, uninflamed gingivae - gingival fibromatosis or drug induced, distinguish on duration and drug history, more likely to be drug induced
- Red, inflamed gingivae - inflammatory hyperplasia or hormonal induced, distinguish by history
- Red, inflamed, pus, ulceration - leukaemia, further investigations
What is squamous cell papilloma?
Following questions on oral mucosa swellings
It is a benign neoplasm which is HPV driven (6 and 11 as 16 and 18 are oncogenic). It is a white cauliflower-like growth which can be pedunculated or sessile. It is common on the palate. Histologically there is an overgrowth of epithelium which is hyperkeratinised hence the white colour. The surface is thrown into fronds (folds) and it has a vascular connective tissue core. Management is to excise with a margin and HPV 6 and 11 are not contagious.
What is Heck’s disease? (focal epithelial hyperplasia)
It is multiple papillomas caused by HPV 13 and 32. There are multiple flat viral warts. It may resolve spontaneously or you can excise. It is rare.
What is fibrous hyperplasia and traumatic neuroma?
Fibrous hyperplasia can be called leaf fibroma and is caused by an ill-fitting denture. It is fibrous connective tissue covered by mucosa.
Traumatic neuroma is a reactive condition. It is haphazard overgrowth of nerve fibres usually caused by trauma. It is often seen in the mental foramen region. It is frequently painful. Histologically you will see scar tissue and lots of nerve fibres in a haphazard arrangement.
What is lipoma?
It is a benign neoplasm composed of fat. It is yellow/pink and has a smooth surface. It is common on the cheek and tongue and the management is to excise. They tend to be quite large and seen on the buccal mucosa. Histologically there are lots of adipocytes.
What is haemangioma?
It is an example of a hamartoma which is proliferation of tissue which is normal for that site. A choristoma is proliferation of tissue which is abnormal for that site for example in the middle of the tongue you can get a nodule of cartilage. There are excess blood vessels. It is localised or diffuse and may bleed excessively so take care. It will blanch under pressure.
What is Sturge Weber syndrome?
It is present from birth (congenital) and has characteristic features:
- Port wine stain which follows the distribution of the trigeminal nerve, it is an overabundance of capillaries near the skin
- Varying degrees of mental retardation/learning difficulties
- Glaucoma
- Seizures
Intraorally you can see gingival swelling and haemangioma.
What is lymphangioma?
It is also a hamartoma. It is similar to haemangioma but is an overgrowth of lymphatic vessels. It has a paler colour clinically.
Common head and neck lymphangioma in neck and floor of mouth is cystic hygroma.
What is a neural tumour?
It is a neurofibroma or neurilemmoma. It is more deep seated and relatively rare. It is firm and mucosa coloured.
What is a granular cell tumour?
It is common on the tongue and has a neural origin.
What is a congenital epulis?
Similar to granular cell tumour histologically but it occurs in neonates.
What may the differential diagnoses be for mucosal swellings?
- Cauliflower like and white - squamous cell papilloma
- Smooth, mucosa coloured, related to denture or other source of trauma - fibrous hyperplasia
- Smooth, yellow - lipma
Red/red-white, related to trauma - pyogenic granuloma - Red/blue - haemangioma, mucocele
Deep seated/normal mucosa - neuroma, neural tumour, salivary gland tumour
When is FNA used?
When you can’t get to a lesion with a scalpel. Deeply seated lesions e.g. lymph nodes in the neck.
What are the sources of pigment?
- Melanin (majority) which is endogenous so produced by the body
- Haemosiderin (endogenous)
- Amalgam and heavy metals (exogenous)
- Chromogenic bacteria (exogenous)
What is haemosiderin?
It is a breakdown product of red blood cells. They are consumed by macrophages and break down. The haem which contains iron breaks down into haemosiderin which stores iron but cannot be used until it breaks down further. Haemosiderin builds up in tissues where there has been damage e.g. haemorrhage. It is brown.
What is melanin?
Melanin is produces by melanocytes (or nevus cells) which are found in the basal third of the epithelium. Melanosoma are packages of melanin found in melanocytes. Melanocytes become visible on histology when they are active or atypical. You usually see melanin pigment in the basal epithelium and it absorbs UV light so protects from the sun. Melanin is transferred to adjacent keratinocytes by membrane bound organelles called melanosomes. There can be increased melanin production without increased melanocytes but if melanocytes increase this is abnormal.
What are the sources of occupational exposure to heavy metals?
- Manufacture of ammunition, dental x-ray films, plumbing, ceramic glazes
- Jobs - lead miners, plumbers, mechanics, glass manufacturers, construction workers, welding, processing of ore, production of paints and pigments
- Agyria is ingesting too much silver
What are chromogenic bacteria?
They are bacteria that produce pigment such as aspergillus and actinomyces. They are often seen in hairy tongue. Bacterial enzymes act on iron in saliva.
What are the types of oral pigmented lesions?
Look at image on lecture and learn this.
There is exogenous and endogenous which is categorised by developmental, acquired and neoplastic.
What information would you need to make a differential diagnosis on a pigmented lesion?
- Name, age, occupation
- History of lesion
- Medical history
- Drug history
- Dental history
- Social history
- Extraoral and intraoral examination
What is an amalgam tattoo?
A pigmented lesion which tends to be very close to where the amalgam is. A radiograph is needed to confirm amalgam and will show a radiopacity in the tissues. A biopsy may not be required.
How can chewing a pencil cause a pigmented lesion?
Chewing a pencil can get lead into the tissues.
How do heavy metals cause pigmented lesions?
Heavy metals include lead, bismuth, mercury, silver, arsenic and gold. They may leach directly into the mucosa from dental restorations and crowns. They are deposited due to drugs containing heavy metals e.g. pepto-bismol. Lead in blood leaks out of gingival tissues as it is in crevicular fluid. It looks similar to an amalgam tattoo histologically.
What is black hairy tongue?
It affects the posterior dorsal tongue and there is a decrease in the normal desquamation process. It is associated with a soft diet, smoking and antibiotic use. There are elongated filiform papillae which may be black/brown/white. Discolouration is caused by chromogenic bacteria, smoking, chlorhexidine and foods. Histologically you may see clusters of aspergillus bacteria. Difficult to treat - avoid smoking.
What are the developmental endogenous pigmented lesions?
- Physiological (melanin)
- Peutz Jehger’s syndrome (melanin)
- Haemochromatosis (haemosiderin)
- Pigmented naevus (melanin)
How can oral pigmented lesions be physiological?
We all have different coloured skin. Symmetrical pigmentation will be seen in gingivae.
What is Peutz Jehger’s?
It is a genetic disorder which is autosomal dominant. There are pigmented mucocutaneous macules, GI polyps usually in the small intestine with an increased risk of malignant change associated with the polyps. The melanotic spots are characteristically small and multiple and are very obvious around the lips. It is seen in children. Histologically there will be an increase in the amount of melanin.
What is haemachromatosis?
It is a rare genetic disorder (autosomal recessive). There is an accelerated rate of intestinal iron absorption leading to raised serum ferritin and transferrin saturation, There is accumulation of iron (as haemosiderin) in the liver and islets of langerhans. This leads to bronze skin pigmentation, liver cirrhosis and diabetes mellitus. It is treated with regular venesection. This leads to fatigue, lethargy and you are more prone to bacterial infections (some bacteria have an affinity for iron).
What is a melanotic naevus?
It is a mole but if it is not well-defined it may be something sinister. Melanin is also produced by nevus cells which are derived from the neural crest. They are found in the skin and mucosa. There are many histological types of nevus which are junctional (epithelium), intradermal/mucosal (connective tissue) or compound (both).
What are the types of acquired endogenous oral pigmented lesion?
- Addison’s disease (melanin)
- Drug induced (melanin)
Post-inflammatory (melanin)
Smoker’s melanosis (melanin)
Melanotic macule (melanin)
What is Addison’s disease?
Approximately 90% of cases are caused by autoimmune disease. There is destruction of the entire adrenal cortex followed by a subsequent lack of adrenocortical hormone. This leads to increased production of adrenocorticotropic hormone ACTH by the anterior pituitary gland. ACTH induces melanocyte stimulating hormone leading to increased pigmentation of the skin and oral mucosa. There are diffuse brown patches on the buccal mucosa, palate, tongue and gingivae. Extra-oral sites include palmer creases and new scars. Patients need steroid cover due to adrenal crises.
What is a melanotic macule?
The histology appears the same as a freckle. It has different histology to a naevus as there are no nevus cells.
What medication can cause drug induced pigmentation?
- Antimalarians - quinacrine, chloroquine, hydroxychloroquine
- Quinidine
- Zidovudine (AZT)
- Tetracycline
- Minocycline
- Chlorpromazine
- Oral contraceptives
- Clofazimine
- Ketoconazole
- Amiodarone
- Busulfan
- Doxorubicin
- Bleomycin
- Cyclophosphamide
What are the three ways drug induced pigmentation happens?
- Increased production of melanin
- Deposition of iron after damage to mucosal vessels
- Deposition of heavy metals in tissues (exogenous)
What is post-inflammatory pigmentation?
Lichen planus destroys basal cells which hold melanin. The melanin is lost to the connective tissue and drops into the lamina propria so brown pigment is seen within lichen planus.
What is smokers melanosis?
There is a protective mechanism of the oral tissues to produce melanin. 21.5% of smokers will have this. It has a similar histology to lichen planus but no basal cell loss.
What are the two types of endogenous neoplastic pigmented lesion?
- Malignant melanoma
- Kaposi’s sarcoma
What is malignant melanoma?
It makes up less than 1% of all oral malignancies. There is proliferation of malignant melanocytes along the junction between the epithelium and connective tissue as well as within the connective tissue. It is seen on the anterior palate and anterior gingivae most commonly. It is seen in men more than women and ages 30-70. It may present with typical signs and symptoms of malignancy such as rapidly enlarging mass associated with ulceration, bleeding, pain and bone destruction. Or it can be asymptomatic, slow growing, brown or black patch with asymmetric and irregular borders. Some are non-pigmented (amelanotic) which can make it difficult to diagnose. It is an aggressive and often fatal disease (worse prognosis than skin lesions). Risk factors are unknown. The treatment is radical surgical excision with clear margins. Radiation and chemotherapy are ineffective which adds to the difficulties associated with management of this malignancy. Over 5 year survival rate – 15%. Every melanoma starts at T3 – so aggressive.
What is Kaposi’s sarcoma?
It is a malignant tumour associated with immunosuppression. It is a hallmark of AIDs caused by HHV-8. There are black/purple lesions orally on the gingivae most commonly. Treatment is excision with or without chemotherapy/radiotherapy. Histologically it can appear similar to melanoma and appear as a bruise.
What is an ulcer?
It is a full thickness loss of the epithelium which exposes the underlying connective tissue. The ulcer is covered by a fibrinopurulent slough. There is underlying granulation tissue and mixed inflammatory infiltrate. They are usually painful. Erosion is partial loss of the epithelium. Histologically there is fibrinopurulent slough with granulation tissue underneath. Primary ulcers begin as ulcers and secondary ulcers begin as vesicles or blisters.
What are the differential diagnoses for ulcers?
- Neoplastic e.g. SCC
- Traumatic e.g. sharp tooth
- Developmental e.g. epidermolysis bullosa
- Manifestation of systemic disease e.g. Crohn’s
- Manifestation of dermatological disease e.g. lichen planus
- Idiopathic e.g. RAS
- Iatrogenic e.g. drugs
- Infective e.g. syphillis, TB, HSV, fungal infections
Give examples of single episode and recurrent episode ulcers?
Take a good history:
- Single episode
Single ulcer e.g. SCC
Multiple ulcers e.g. herpes zoster
- Recurrent episode
Single ulcer e.g. mucocutaneous disorders
Multiple ulcers e.g. RAS, mucocutaneous disorders
- Some causes fit into many categories e.g. drugs
What are the causes of single episode ulcers?
- Trauma - physical, chemical, thermal, factitious
- Malignancy - SCC, salivary neoplasm, lymphoma
- Infective - TB, syphillis, HSV
- Drugs - methotrexate (immunosuppressive - target cells that are breaking down quickly such as epithelium)
How would you treat a single episode traumatic ulcer?
- Reassurance
- Remove the cause
Consider Difflam and Corsodyl - Should show signs of improvement
What are the signs of a malignant ulcer?
Look out for a raised ulcer with raised borders. If there is a loss of epithelium there should be no growth. Look out for lateral border of the tongue and floor of mouth as these are common areas. Any ulcer that is over 3 weeks in duration of unexplained cause should be regarded as malignant until proven otherwise (biopsy). Don’t be afraid of being wrong.
What are the causes of single episode multiple ulcers?
- Herpes simplex
- Herpes zoster
- Erythema multiforme
- Hand, foot and mouth
- Herpangina
- Oral lichen planus
- Vesticulo-bullous disorders
- Iatrogenic e.g. drugs