Oral Pigmentation Flashcards
What is the name of the cells that produce melanin?
Melanoblasts
What are the most common sites for physiological pigmentation?
Gingivae, buccal mucosa
Explain the disease melasma
Melasma is a disease resulting is patchy discolouration of the skin. Caused by genetics, sun exppsure and hormones
Smokers melanosis:
- What & of smokers have this?
- What causes the change in pigmentation?
- What colour is the pigmentation?
- What sites does it affect?
- How often after cessation of the habit foes it resolve?
- 20%
- Chemicals in the cigarettes interfere with melanin synthesis
- Brown / black
- Hard palate, gingivae, buccal mucosa
- Often resolves within 3 weeks of habit
Does a melanotic macule occur due to an increase in melanin production or increase in number of melanocytes?
Melanin production
What are melanotic macules? Do they need treatment?
Well defined, flat brown lesions commonly affecting the lips, gingivae, buccal mucosa and palate.
No treatment required
What is lentigo and how does it occur?
Increase in the number of melanocytes associated with sun exposure or damage.
Forms flat brown macules on sun exposed skin of older patients.
What is Peutz Jehger syndrome?
A rare disease causing muco-cuteanous pigmented macules.
Flat black/brown spots which occur on the lower lip but can affect the buccal mucosa, the tongue and palate. - Due to increase in amount of melanin production.
Associated with intestinal polyposis.
What is addison’s disease and how does it affect the buccal mucosa?
- Primary adrenal insufficiency (lack of cortisol reduced resulting in over-production of ACTH from the pituitary gland)
- Increased ACTH promotes melanogenesis and leads to purple/black irregularly shaped multiple lesions on the buccal mucosa
What is LEOPARD syndrome?
L = lentigenes = pigmented macules
E = ECG abnormalities
O = ocular hypertelorism (wide spacing of eyes)
P = pulmonary stenosis (obstruction of blood flow out right ventricle)
A = abnormal genitals
R = retarded growth
D = deafness
What are the 3 stages of melanocytic naevi formation? = moles
1) Junctional stage = neoplastic melanocytes sit entirely within epithelium and proliferate
2) Compound stage = melanocytes migrate down into the connective tissue
3) Intra dermal stage = neoplastic melanocytes sit within the connective tissue
What are some suspicious features of a pigmented patch?
- Asymmetrical
- Irregular borders
- Variation in colour
- Diameter > 0.6mm
- Erythema
Explain the stages of a melanoma forming
1) Melanocytic dysplasia: melanomas in situ, increase in number of melanocytes within epithelium that are abnormal in size
2) Radical growth phase: melanocytes spread across the epithelium and migrate towards the epidermis. Some growth of cells into the connective tissue but most growth is lateral
3) Accumulating mutations causes atypical melanocytes to infiltrate through the basement membrane into the connective tissue
4) vertical growth phase: melanocytes grow downwards into connective tissue
What is black hairy tongue caused by?
Keratin on the surface of the tongue in the filiform papillae.
Picks up staining from bacteria, food and smoking.
Treatment = smoking cessation, tongue scraping, improved OH
Why does an amalgam tattoo occur and how is it recognised?
Fragments of amalgam break off and are embedded within the oral mucosa.
<5mm, grey/blue appearance, adjacent to the amalgam
