Oral Medicine Orofacial Pain

Question 1

Allodynia

Answer 1

pain from normally non-painful stimuli

Question 2

Hyperalgesia

Answer 2

increased response to painful stimuli

Question 3

Describe the pathophysiology of neuropathic pain

Peripheral and Central mechanisms

Answer 3

Peripheral: neuron hyperexcitability and loss of inhibitory controls
Central: neuron hyperexcitability
Results in abnormal discharges and therefore neuropathic pain

Question 4

List physchosocial factors that contribute to pain perception

Answer 4

Age, sex, stressors in life, culture, anxiety, fatigue, previous pain experiences

Question 5

Neuralgia

Answer 5

pain in distribution of 1 or more nerves

Question 6

Describe the neurophysiology of trigeminal neuralgia

2 mechanisms

Answer 6

1. Ectopic impulses: increased number or intesity of action potentials
2. Ephaptic Transmission: impulses skip between neurons in areas where demyelination has occured

Question 7

Describe the population most at risk of trigeminal neuralgia

Answer 7

> 50 years
Female
Previous infection with varicella zoster virus (predisposed to shingles)

Question 8

Describe the type of pain typically experienced in trigeminal neuralgia

Answer 8

Short, sharp pain
Burning
Distribution along a branch of CNV
Unilateral
Aggravated by trigger points
Episodic pain followed by periods of remission

Question 9

List 4 medications that are used to treat trigeminal neuralgia

Answer 9

Carbamazepine
Gabapentin
Pregablin
Sodium Valproate

Question 10

Which 2 medications used in treatment of TN have a higher risk of causing liver damage

Answer 10

Carbamazepine and sodium valproate

Blood work should be done before and during treatment with these

Question 11

List 4 differentials for trigeminal neuralgia

Answer 11

Dental pain
MS
post- herpetic neuralgia
cluster headache/ TMD

Question 12

List 5 common sites affected by glossopharyngeal neuralgia

Answer 12

1. Post 1/3 tongue
2. ear
3. nasopharynx
4. oropharynx
5. tonsils

Question 13

Describe how IX neuralgia can be differentiated from V neuralgia

Answer 13

Patient bites on something (bite block, end of instrument etc.).
If no pain is experienced, but pain is experienced on swallowing, then highly likely to be IX neuralgia

Question 14

List 3 differential diagnoses for glossopharyngeal neuralgia

Answer 14

1. tonsillar SCC
2. oropharyngeal carcinoma
3. brain vascular compression/tumour

Question 15

What is Eagle’s syndrome

Answer 15

Pain similar to glossopharyngeal neuralgia caused by elongation and calcification of the styloid process + stylohyoid ligament, which pressed on the glossopharyngeal nerve causing neuralgia.

Question 16

What % of people infected with herpes zoster virus experience post-herpetic neuralgia?

Answer 16

10%

Question 17

How can the risk of developing post-herpetic neuralgia be decreased?

Answer 17

Early treatment with anti-virals or anticonvulsants (after symptoms have appeared)

Question 18

What is the typical I/O presentation of herpes zoster virus?

Answer 18

Unilateral blistering commonly seen on hard palate
Prior to blisters, sharp burning pain may be experienced

Question 19

In what ganglion does herpes zoster virus remain latent?

Answer 19

Semilunar ganglion (sensory ganglion of CNV)

Question 20

What is Ramsay Hunt Syndrom?

Answer 20

Herpes Zoster Virus affecting the facial nerve causes unilateral facial paralysis and hearing loss

Question 21

Which division of CNV is most commonly affected by herpes zoster virus?

Answer 21

CNV1 (opthalmic division)

Question 22

Why can sinusitis mimic dental pain?

Answer 22

The nerves that innervate membrane of maxillary sinus also innervate maxillary teeth.

Question 23

Describe the pain experienced with sinusitis

Answer 23

Dull throbbing pain that is worse with postural change (bending over), blocked sinuses
Skin over sinus painful to touch (allodynia)
dental pain to percussion and cold

Question 24

List 3 sinuses that can be affected by sinusitis

Answer 24

Paranasal
Maxillary
Ethmoid

Question 25

What is temporal arteritis?

Answer 25

Inflammation of the temporal artery

Question 26

What is a complication of termporal arteritis?

Answer 26

Blindness

Question 27

What are common symptoms of temporal arteritis?

Answer 27

Pain on chewing which is relieved at rest
Pain in jaw/tongue

Question 28

What blood markers are characteristic of temporal arteritis

Answer 28

Elevated erythrocyte sedementation rate
Elevated C reactive proteins

Question 29

A patient presented with aching pain in LHS jaw which extends down side of neck. Ptn also has pain in upper back. What is the diagnosis and management?

Answer 29

Angina pectoris, refer to E.D