Oral Mucosa: Pigmented Lesion Flashcards
What can cause a “furry” appearance on the tongue?
Overgrowth of filiform papillae on tongue = dark furry appearance
Sources of pigment in the mucosa?
Melanin (majority)
Haemosiderin = breakdown product of RBCs
Amalgam or heavy metals
Chromogenic bacteria
What is haemosiderin? Features?
Breakdown product of RBCs
Iron stored
Brown pigment
What is melanin?
Features?
Produces by melanocytes (or nevus cells)
Useful at absorbing UV light
Found in basal 3rd of epithelium
Black/brown
Melanin is transferred to adjacent keratinocytes via membrane bound organelles called melanosomes
Orangey brown pigment on histology
Increased melanin production without increased number of melanocytes (if increase in melanocytes - sign of abnormality)
Examples of heavy metals?
What can heavy metals lead to?
Lead, bismuth, mercury, silver, arsenic and gold
May leach into mucosa from restorations and crowns
Deposited due to drugs containing heavy metals e.g. peto-bismal (med for stomach ache, diarrhoea) combines with sulphur in saliva bismuth sulphide (insoluble)
How are people exposed to heavy metals?
Manufacture of ammunition, dental x-ray films, plumbing, ceramic glazing
Jobs: Lead miners, plumbers, mechanics, glass manufacturers, construction workers, welders, making paints and pigments
What is argyria?
When someone has had too much silver = accumulates in skin
Chromogenic bacteria features?
Bacteria that produce pigment
Aspergillus and actinomyces
Often seen in hairy tongue
Bacterial enzymes act on iron in saliva = tissues go brown or black
Oral pigmented lesions classification - exogenous?
Amalgam tattoo
Foreign body tattoo
Heavy metal (occupation or drugs)
Black hairy tongue (bacteria)
Oral pigmented lesions classification - endogenous?
Developmental: Physiological (melanin) Peutz jehger's syndrome (melanin) Haemachromatosis (haemosiderin) Pigmented naevus (melanin)
Acquired: Addison's disease (melanin) Drug induced (melanin) Post inflammatory (melanin) Smoker's melanosis (melanin) Melanotic macule (melanin)
Neoplastic
Melanoma (melanin) - rare
How to form a diagnosis for pigmented lesions?
HISTORY: Name, age, occupation History of lesion - how long, one area or several, symptoms, size, does it go away MH Drug history DH SH Extra oral and intraoral examination
Amalgam tattoo - how can they occur?
Amalgam gets into tissues by leaching out of restoration If tooth extracted with amalgam restoration and restoration crumbled = amalgam in socket if not irrigated Deep class II - amalgam pushed down into the gingival crevice
How to manage amalgam tattoo?
Reassure pt no complications
Refer for biopsy if irregular borders
Can do periapical radiograph and see if radiopaque material in tissues = amalgam
What else can cause foreign body tattoos?
Pencil lead - do not chew
Lead toxicity - blue/black line around gingival margin - looks similar to amalgam tattoo on histology
Black hairy tongue features?
Affects posterior dorsal tongue
Decrease in normal desquamation process - associated with soft diet, smoking, antibiotic use
Elongated filiform papillae - can be black, brown, white
Discolouration caused by chromogenic bacteria, chlorhexidine, foods, smoking
How to manage black hairy tongue?
Difficult to treat - recommend tongue scraper
Avoid smoking, chlorhexidine
May resolve after finishing broad spec antibiotics
NO BIOPSY NEEDED
Peutz-Jegher syndrome features?
Genetic disorder - autosomal dominant
Pigmented mucocutaneous macules/freckles, GI polyps, usually small intestine with normal increased risk of malignant change associated with polyps
Freckles around mouth but mostly limited to lips, present in childhood = dentist should refer
Melanotic spots characteristically mall and multiple
V obvious around lips
Syndrome has higher risk of developing cancer
Peutz-jegher syndrome freackles histology?
Increased melanin
Haemochromatosis?
Genetic disorder - autosomal recessive
Accelerated rate of intestinal iron absorption
Raised serum ferritin and transferrin saturation
Accumulation of iron
Leads to bronze skin pigmentation, liver cirrhosis, diabetes
mellitus
Bronze skin due to build up of haemosiderin
Treated with regular venesection = blood removal
Melanocytic nevus?
= Mole in mouth
Well defined, black/brown
Usually on palate
If raised/poorly defined = could be melanoma = biopsy
In nevus, what also produces melanin? What does this mean?
In nevus melanin is also synthesised by nevus cells which are derived from the neural crest
Found in skin and mucosa
Can produce different histological types of naevus:
- Junctional (epithelium)
- Intradermal/mucosal (CT)
- Compound (both)
All are benign, excise if rase concern
Addison’s disease - what is it? What can it cause?
Destruction of adrenal cortex = produces cortisol
Most are autoimmune disease
Lack of adrenocortical hormone:
- Increased production of adrenocorticotropic hormone (ACTH) by anterior pituitary gland
- This induces melanocyte stimulating hormone = increase pigmentation of skin and oral mucosa
Addison’s disease - dental relevance?
Diffuse brown patches on buccal mucosa, palate and tongue and gingivae
Extraoral sites - palmar creases, new scars
Pt will need steroid cover
Risk of adrenal crisis = BG drops, BP drops, can faint and go unconscious
Pigmentation around mouth and inside mouth
Melanotic macule (freckle)?
Brown/black macules in oral cavity
Lighter brown than nevi and different histology
Pt reassurance
Drug induced pigmented lesions - what medications can cause discolouration?
Minocycline = antibiotic for acne = stains bone (blue/grey) - sometimes does not go once stop medication
Antimalarials: quinacrine, chloroquine Tetracycline Oral contraceptives Clofazimine Bleomycin Cyclophosphamide Chemotherapy drugs
How to manage drug induced pigmentation?
How is it causes?
Talk with GP
Increased production of melanin
Deposition of heavy metal in tissues (exogenous pigment)
Deposition of iron atfer damage to mucosal vessels
Post inflammatory pigmented lesions - how does this occur?
Melanin can drop into the lamina propria
Basal cell loss
= Brown patch e.g. within lichen planus
What percentage of smokers will have smokers melanosis?
20% of smokers
Malignant melanoma features?
<1% of all oral malignancies
Proliferation of malignant melanocytes along the junction between the epithelial and CT, as well as within the CT
Anterior palate and anterior gingvae common sites
Starts at T3 = aggressive
4th-7th decade
Men>women
Asymp, slow growing brown or black patch with asymmetric and irregular borders VS rapidly enlarging mass associated with ulceration, bleeding, pain, bone destruction
Some are non-pigmented (amelanotic)
Aggressive and often fatal disease (worse prognosis than skin lesions)
5yr survival rate of malignant melanoma?
15%
Kaposi sarcoma features?
Malignant tumour Associated with immunosuppression Hallmark of AIDS Caused by HHV8 Black/purple lesions orally, gingivae most commonly Forms vascular spaces filled with blood
Kaposi’s sarcoma tx?
Excision +/- chemotherapy/radiotherapy
Other oral manifestations of AIDS?
Acute pseudomembranous candidiasis
Oral hairy leukoplakia
ANUG
