OM-Lichen planus

Question 1

Name the 3 types of lichen planus?

Answer 1

Reticular
Atrophic (subtype)
Erosive. (subtype)

Question 2

Name & describe this type of lichen planus?

Answer 2

Reticular- lacey patterns of white lines running across the mucosa.

Question 3

Name this type of lichen planus

Answer 3

Atrophic- an erythematous change to the mucosa.

Question 4

Name this type of lichen planus?

Answer 4

Erosive- Atrophy extends to the point of having no epithelium at all. There is a yellowy fibrous covering over the base of the connective tissue.

Question 5

What are the commonly seen histological features of lichen planus

Answer 5

• Chronic inflammatory cell infiltrate (lymphocytic band hugging the basement membrane)
• Saw tooth rete ridges.
• Basal cell damage
• Patchy acanthosis
• Parakeratosis.

Question 6

What causes lichen planus?

Answer 6

It is the final common pathway from the immune response after many different triggers.

Question 7

What is a lichenoid reaction?

Answer 7

When the cause of the oral lesion is known.

Question 8

What are the symptoms for lichen planus?

Answer 8

Often none
Sensitivity to hot/ spicy food
Burning sensation

Question 9

On what sites do you find lichen planus?

Answer 9

Buccal mucosa.
Gingivae
Tongue (Lateral aspect/dorsum)
Lips
Palate

Question 10

What is desquamative gingivitis ?

Answer 10

If the lichen planus lesion is only found on the gingivae

Question 11

What is the most common site for lichen planus?

Answer 11

Buccal mucosa.

Question 12

Describe the appearance of gingival lichen planus?

Answer 12

Erythematous gingivae.
No swelling in the gingival margins
Can be a simple reticular pattern

Question 13

How does lichen planus present on the dorsum of the tongue?

Answer 13

Loss of papillae & smooth tongue surfaces.

Question 14

What is the normal cause of lichen planus on the dorsum of the tongue?

Answer 14

normally idiopathic

Question 15

What is the most likely cause of lichen planus on the lateral aspect of the tongue?

Answer 15

Drug/Amalgam trigger

Question 16

What is characteristic of a lichen planus reaction to drugs?

Answer 16

Widespread.
Often bilateral and mirrored (Same lesion on L and R)
Often poorly responsive to standard steroid treatment.

Question 17

What medications commonly cause lichenoid reactions?

Answer 17

ACE inhibitors
Beta-adrenergic blockers
Diuretics (e.g. bendroflumethiazide/ Frusemide)
NSAIDs
DMARDs

Question 18

In what situations would it be beneficial to stop the patient’s drugs to remove the lichen planus?

Answer 18

If the lichen planus has significant symptoms requiring maximum topical or systemic treatment

Question 19

What is the best way to check if an amalgam restoration is causing the lichen planus?

Answer 19

Get the patient to occlude together and check the proximity of the lesion to the restoration

Question 20

What are the treatment options for lichen planus caused by an amalgam restoration?

Answer 20

Leave (if lichen planus is asymptomatic)
Replace amalgam restoration with a composite.

Question 21

What tests do we do if the cause of the lichen planus is not clear?

Answer 21

Biopsy
Haematinics
FBC
Lupus antibody test.

Question 22

How do we manage lichen planus in patients with mild symptoms?

Answer 22

0.2% Chlorohexidine mouthwash
Benzdamine mouthwash
Avoid SLS toothpaste.

Question 23

How do we manage patients with persisting symptomatic lichen panus lesions?

Answer 23

Beclomethasone MDI 0.5mg/puff - 2 puffs 2-3xdaily.
Betamethasone rinse- 1mg/10ml/2 mins/ twice daily.

Question 24

How is lichen planus managed in hospital?

Answer 24

Higher strength topical steroids (clobetasol)
Topical tacrolimus.
Hydroxychloroquine.
Systemic immunomodulators (Azathioprine/Mycophenolate)

Question 25

What can we use to help with the treatment of gingival lichen planus?

Answer 25

A gingival veneer to hold the topical steroid gel (Sinylar) in contact with the gums.

Question 26

Name 2 other conditions that look like lichen planus?

Answer 26

Lupus erythematosis Graft verus host disease

Question 27

What is graft versus host disease and how does the histology compare to lichen planus?

Answer 27

This is commonly found in patients with stem cell or bone marrow transplants The histology is very similar to lichen planus.

Question 28

What is Lupus Erythematosis and how does the histology compare to lichen planus?

Answer 28

This is a host immune system disease. The histology- the inflammatory infiltrate is much further away from the basement membrane than that in lichen planus.

Question 29

When are atrophic and erosive lichen planus accepted as subtypes

Answer 29

When there are reticular lesions elsewhere in the mouth

Question 30

How do we distinguish between lichen planus and a lichenoid lesion

Answer 30

Lichen planus meets all the clinical and histopathological criteria. Oral lichenoid lesion- may be compatable (resembles it) but not meet the criteria

Question 31

What are the clinical criteria for lichen planus?

Answer 31

presence of bilateral symmetrical lesions Presence of a lace-like network of slightly raised gray-white lines (Reticular pattern) Erosive or atrophic are only accepted if there are reticular lesions elsewhere

Question 32

What are the histopathological criteria for lichen planus?

Answer 32

Presence of a well defined bandlike zone of cellular infiltration that is confined to the superficial part of the connective tissues- consisting mainly of lymphocytes. Signs of liquefaction degneration in the basal cell layer. Absense of epithelial dysplasia If the histopathologic features are less obvious we say it is histopathologically compatable.

Question 33

How does a biopsy showing keratosis of unknown significance affect our treatment?

Answer 33

We don't discharge the patient as it could become a problem in the future

Question 34

How can oral lichenoid lesions be classified?

Answer 34

Amalagam restoratation topographically associated OLL Drug related OLL OLL in chronic graft versus host disease OLL unclassified (none of the above/ not meeting all the LP classifications.

Question 35

What drives the cancer development from lichen planus?

Answer 35

Inflammation.

Question 36

Discuss risks of replacing an amaglam restoration to treat Lichen planus

Answer 36

 Replacement may not improve the reaction  Removing the existing restoration could damage the tooth (Deep restoration/pulpal exposure)

Question 37

What is the risk of not replacing an amalgam restoration causing a lichenoid reaction ?

Answer 37

1% chance of malignant change- this can be monitored through clinical images. We are more concerned about this risk in high risk patients (smokers/ smokers & drinkers)