Orofacial Pain Flashcards
How can pain often ‘refer’ in the head and neck?
Many nerves share a common pathway
- stimulation of one nerve can cause stimulation of common pathway, leading to referred pain
When pain is felt and a nerve stimulated, these often run to spinal cord or other nerve centres in brain
- multiple nerves can converge in these areas and synapses can induce pain stimulation in other nerves
Afferent vs efferent?
Afferent = sensory to Brain
Efferent = brain to muscle motor
How can autonomic nerve referred pain occur?
Autonomic afferent and efferent
Afferent enters CNS and goes to brain
- managed same was as efferent signals and pain induced
E.g. cardiac pain felt as somatic pain yet it has no somatic heart supply
How does an autonomic reflex arc work? Give example
Sensory afferent information transported to spinal cord
Synapse to efferent motor neurone which travels through sympathetic ganglion to effector organ which produces a response
Nasal congestion
increased blood flow - swelling and going red
How does tissue damage in the periphery produce a pain response?
Tissue damage causes chemical mediators such as
- bradykinin and prostaglandins
These produce action potential nociceptor which transmits it to CNS
How does melzac and walls gate control of pain work
‘Gate’ in spinal cord allows pain through to be sent to brain
Sensory input e.g. hot stimulus on hand
Nociceptor sends signal to spinal cord
Also touch, non nociceptive signal is sent to the spinal cord
Strong or repetitive non nocieptive input can close gate in spinal cord to prevent pain input being sent to the brain, thus distracting brain from pain, leading to reduced feeling
E.g. holding hot dinner plate but dont want to drop food
How would one take a pain assessment?
Socrates
Physical symptoms - McGill pain scores
Emotional symptoms - psychological scores
What is nociceptive vs neuropathic pain?
Nociceptive
- activity in neural pathways in response to potentially tissue damaging stimuli
Neuropathic
- initiated or caused by primary lesion or dysfunction in nervous system
What is neuropathic pain typically like?
Constant burning / aching
Fixed location and often fixed intensity
Usually following a history of ‘injury’
Give some remedies for neuropathic pain
Systemic meds
- pregabalin
- opioids
Topical meds
- capsaicin
- ketamine
Physical
- TENS
- acupuncture
Psychological
- distraction
What is atypical odontalgia?
Dental pain without dental pathology
Pain free or mild between episodes, then intense unbearable pain
What is persistent idiopathic facial pain?
Pain which poorly fits into standard chronic pain symptoms such as
- tmd
- Trigeminal neuralgia
- migraine
Often high disability level, autonomic component
Management of persistent idiopathic facial pain?
Believe patient and do not blame any associated depression
Do not increase damage with surgery
Adopt holistic strategy
- QOL
- realistic outcomes
What is oral dysaesthesia?
Some symptoms?
Abnormal sensory PERCEPTION in the ABSENCE of ABNORMAL stimulus
So basically feeling a different perception even when there is no abnormal stimulus
Burning
Dry mouth
Paraesthesia
Dysguesia - altered taste
Most common predisposing factors for oral dysaesthesia?
Haematinic deficiency
Fungal / viral infection
Women > men
