Oral Medicine Orofacial Pain Flashcards
Allodynia
pain from normally non-painful stimuli
Hyperalgesia
increased response to painful stimuli
Describe the pathophysiology of neuropathic pain
Peripheral and Central mechanisms
Peripheral: neuron hyperexcitability and loss of inhibitory controls
Central: neuron hyperexcitability
Results in abnormal discharges and therefore neuropathic pain
List physchosocial factors that contribute to pain perception
Age, sex, stressors in life, culture, anxiety, fatigue, previous pain experiences
Neuralgia
pain in distribution of 1 or more nerves
Describe the neurophysiology of trigeminal neuralgia
2 mechanisms
- Ectopic impulses: increased number or intesity of action potentials
- Ephaptic Transmission: impulses skip between neurons in areas where demyelination has occured
Describe the population most at risk of trigeminal neuralgia
> 50 years
Female
Previous infection with varicella zoster virus (predisposed to shingles)
Describe the type of pain typically experienced in trigeminal neuralgia
Short, sharp pain
Burning
Distribution along a branch of CNV
Unilateral
Aggravated by trigger points
Episodic pain followed by periods of remission
List 4 medications that are used to treat trigeminal neuralgia
Carbamazepine
Gabapentin
Pregablin
Sodium Valproate
Which 2 medications used in treatment of TN have a higher risk of causing liver damage
Carbamazepine and sodium valproate
Blood work should be done before and during treatment with these
List 4 differentials for trigeminal neuralgia
Dental pain
MS
post- herpetic neuralgia
cluster headache/ TMD
List 5 common sites affected by glossopharyngeal neuralgia
- Post 1/3 tongue
- ear
- nasopharynx
- oropharynx
- tonsils
Describe how IX neuralgia can be differentiated from V neuralgia
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
List 3 differential diagnoses for glossopharyngeal neuralgia
- tonsillar SCC
- oropharyngeal carcinoma
- brain vascular compression/tumour
What is Eagle’s syndrome
Pain similar to glossopharyngeal neuralgia caused by elongation and calcification of the styloid process + stylohyoid ligament, which pressed on the glossopharyngeal nerve causing neuralgia.
What % of people infected with herpes zoster virus experience post-herpetic neuralgia?
10%
How can the risk of developing post-herpetic neuralgia be decreased?
Early treatment with anti-virals or anticonvulsants (after symptoms have appeared)
What is the typical I/O presentation of herpes zoster virus?
Unilateral blistering commonly seen on hard palate
Prior to blisters, sharp burning pain may be experienced
In what ganglion does herpes zoster virus remain latent?
Semilunar ganglion (sensory ganglion of CNV)
What is Ramsay Hunt Syndrom?
Herpes Zoster Virus affecting the facial nerve causes unilateral facial paralysis and hearing loss
Which division of CNV is most commonly affected by herpes zoster virus?
CNV1 (opthalmic division)
Why can sinusitis mimic dental pain?
The nerves that innervate membrane of maxillary sinus also innervate maxillary teeth.
Describe the pain experienced with sinusitis
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
List 3 sinuses that can be affected by sinusitis
Paranasal
Maxillary
Ethmoid
What is temporal arteritis?
Inflammation of the temporal artery
What is a complication of termporal arteritis?
Blindness
What are common symptoms of temporal arteritis?
Pain on chewing which is relieved at rest
Pain in jaw/tongue
What blood markers are characteristic of temporal arteritis
Elevated erythrocyte sedementation rate
Elevated C reactive proteins
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?
Angina pectoris, refer to E.D
