Facial pain

Question 1

What is temporomandibular joint dysfunction

Answer 1

Term for pain and discomfort around face and mandible of jaw due to muscle spasm or joint itself

Question 2

Symtpoms of temporomandibular joint dysfunction

Answer 2

Joint stiffness, popping, clicking when chewing, pain in jaw, ear ache

Question 3

Epidemiology of temporomandibular joint dysfunction

Answer 3

Very common, esp. in those with migraine + TTH

F>M

Requires full dental assessment to exclude structural cause

Question 4

Clinical features of temporomandibular joint dysfunction

Answer 4

• Jaw and facial pain
• Pain over temporalis and masseter muscle
• Restricted movements
• Mandibular clicking and crepitation

Question 5

Which cranial nerve innervates the muscles of mastication?

Answer 5

Trigeminal

Mandibular branch (V3)

Question 6

Causes of temporomandubular joint dysfunction

Answer 6

Intra-articular: abnormal structure of joing leading to mechanical dysfunction e.g. osteoarthritis, trauma

Extra-articular: overuse of masticatory muscles (bruxism/ teeth grinding), chronic chewing leading to degenerative change

Question 7

Diagnosis of temporomandibular joint dysfunction

Answer 7

Usually clinical

Full dental assessment needed

C-ray can show abnormal anatomy

Question 8

Management of temporomandibular joint dysfunction

Answer 8

Explanation + reassurance

Simple analgesia

Jaw exercises

Dental splints to prevent chewing and grinding

Question 9

What is trigeminal neuralgia?

Answer 9

Severe facial pain

Question 10

Discuss the trigeminal nerve

Answer 10

Cranial nerve V

Trigeminal ganglion has 3 divisions

1. V1: Opthalmic branch
2. V2: maxillary division
3. V3: mandibular division

Question 11

Epidemiology of trigeminal neuralgia

Answer 11

3 per 100,000 annually

Generally affects those 40+

Incidence increases with age

Main risk factor is HTN

M>F

Question 12

Aetiology of trigeminal neuralgia

Answer 12

Usually idiopathic

Can occurur due to lesion of trigeminal nucleus or nerve root e.g. MS/ stroke

Compression of the nerve by the superior cerebellar artery leads to irritation and demyelination of the nerve leading to abnormal discharges

Question 13

Clinical features of trigeminal neuralgia

Answer 13

• Shooting, stabbing, electric shock sensation over face
• Usually doesn;t affects V1 branch - pain felt over the V2 and V3 distribution
• Pain short lasting but can occur in prolonged episodes
• Patients report that they avoid sensory stimulation of that side of face e.g. not shaving or avoiding brushing teeth
• Usually no physical signs
• If ganglion damage there may be weakness or sensory loss

Question 14

When to suspect trigeminal neuralgia

Answer 14

Severe, shock like pain

97% unilateral

Short lived pain

Recurrent attacks during day

Remission for weeks-months but remission periods get shorter

Pain provoked by light tough to face

Some patients have autonomic symptoms: lacrimation, rhinorrhoea, facial sweating

Question 15

Investigations for trigeminal neuralgia

Answer 15

Examine face and oral cavity to rule out dental cause and detect abnormalities

MRI or CT to exclude nerve compression: tumours, masses, MS, epider,pid/ dermoid/ arachnoid cyst, aneurysm, AVM

Red flags: sensory change, deafness, hx of skin lesions, pain only in V1, family hx of MS, onset <40yrs

Question 16

Management of trigeminal neuralgia

Answer 16

1st line = carbamazepine

Once pain in remission reduce dose gradually to lowest possible maintenance level or discontinue until further attack

If carbamazepine doesn’t work - refer to pain specialist

Surgery may be indicated if medication doesn’t work: gamma knife, radiofrequency ablation, decompression of dorsal root (high success rate)