Oral Med Flashcards
What are the 2 main systems for classifying orofacial pain?
- International classification of Headache Disorders Edition 3
- International Classification of Orofacial Pain 1st Edition 2020
What are the 6 groups/categories of orofacial pain?
- Orofacial pain attributed to disorders of dentoalveolar and anatomically related structures
- Myofascial orofacial pain
- Temporomandibular joint (TMJ) pain
- Orofacial pain attributed to lesion or disease of the cranial nerves
- Orofacial pains resembling presentations of primary headaches
- Idiopathic orofacial pain
What are the 2 subtypes of “orofacial pain attributed to lesion or disease of the cranial nerves”.
- Pain attributed to lesion or disease of the trigeminal nerve
- Pain attributed to lesion or disease of the glossopharyngeal nerve
Name 2 conditions of “pain attributed to lesion or disease of the trigeminal nerve”.
- Trigeminal neuralgia
- Painful trigeminal neuropathies
Name 2 coniditons of “pain attributed to lesion or disease of the glossopharyngeal nerve”.
- Glossopharyngral neuralgia
- Painful glossopharyngeal neuropathies
Name 4 conditions of “orofacial pains resembling presentation of primary headaches”.
- Migraine
- Tension type headache (TTH)
- Trigeminal autonomic cephalalgias (TACs)
- Other primary headache disorders
Name 3 conditions of “idiopathic orofacial pain”.
- Burning mouth syndrome (BMS)
- Persistent idiopathic facial pain (PIFP)
- Persistent idiopathic dentoalveolar pain
Give a definition of trigeminal neuralgia
- Limited to the distribution of one or more divisions of the trigeminal nerve
- Normally unilateral
- Pain comes on very suddenly and ends just as suddenly
- Pain doesnt last very long but when it is there it is severe
- Pain like an electric shock
- Has recurrent bursts of this pain
- Pain usually triggered by an innocuous stimuli (a stimuli that wouldnt normally cause pain eg touching face)
State the diagnostic criteria for trigeminal neuralgia.
A: Recurrent paroxsyms of unilateral facial pain in the distribution(s) of one or more divisions of the trigeminal nerve, with no radiation beyond, and fulfilling criteria B and C.
B: Pain has all of the following characteristics:
- Lasting from a fraction of a second to 2 minutes
- Severe intensity
- Electric shock like, shooting, stabbing, or sharp in quality
C: Precipitated by innocuous stimuli within the affected trigeminal distribution
D: Not better accounted for by another ICHD-3 diagnosis
What is the incidence of trigeminal neuralgia?
- 4-13 per 100,000
- Age: 50-60 years (unusual under 40 to have this)
- Females > Males
What are risk factors for trigeminal neuralgia?
- Hypertension
- Stroke
What % of trigeminal neuralgia is related to dental treatment?
22%
What % of patients have pain free periods which lasts either days, weeks, months or years?
73%
Should trigeminal neuralgia raise concerns of an underlying disease causing this?
Yes
The maxilla and mandibular division is the most commonly affected branches of trigeminal neuralgia, what % affects the opthalmic branch?
5%
In what % of cases will the patient be able to identify a trigger zone for trigeminal neuralgia?
50%
What % of cases have no relieving factors although warmth and rest may be helpful?
65%
What is a refractory period?
After the pain has been triggered, there is a period of time where the pain wont recur even if a trigger is re-applied
Trigeminal neuralgia pain is so severe is makes patients cry and if left untreated can lead to depression and anxiety. True or false?
True.
What 3 categories is trigeminal neuralgia split into?
- Classical trigeminal neuralgia
- Secondary trigeminal neuralgia
- Idiopathic trigeminal neuralgia
Give a description of classical trigeminal neuralgia.
Trigeminal neuralgia developing without apparent cause other than neurovascular compression.
What is the diagnostic criteria for classical trigeminal neuralgia?
- Reccurent paroxysms of unilateral facial pain fulfilling criteria for trigeminal neuralgia
- Demonstration on MRI or during surgery of neurovascular compression (not simply contact), with morphological changes in the trigeminal nerve root in the posterior cranial fossa.
What is the root entry zone?
The point where the peripheral and central myelins of Schwann cells and astrocytes meet
It is hypothesised that the morphological changes of the trigeminal nerve causes abnormal firing of the nerve: true or false?
true
What is classical trigeminal neuralgia with concomitant continuous pain?
Classical trigeminal neuralgia with persistent background facial pain.
- Will have recurrent paroxysms of unilateral facial pain fulfilling criteria for classical trigeminal neuralgia but will have concomitant continuous or near-continuous pain between attacks in the affected trigeminal distribution.
What is secondary trigeminal neuralgia?
Trigeminal neuralgia caused by an underlying disease. Clinical examination shows sensory changes in a significant proportion of these patients.
What is the diagnostic criteria for secondary trigeminal neuralgia?
- Recurrent paroxysms of unilateral facial pain fulfilling the criteria for trigeminal neuralgia, either purely paroxysms or associated with concomitant continuous or near-continuous pain.
- An underlying disease has been demonstrated that is known to be able to cause, and explaining the neuralgia.
What are 3 underlying diseases that are associated with secondary trigeminal neuralgia?
- Trigeminal neuralgia associated to multiple schlerosis (demyelination)
- Trigeminal neuralgia associated to space occupying lesion such as a cyst or tumour causing morphological changes.
- Trigeminal neuralgia attributed to another cause
What are some clinical features associated with secondary trigeminal neuralgia and what kind of imaging would you take?
- Tend to be patients <30 years
- Tend to have trigeminal sensory deficits
- Tend to have a bilateral trigeminal neuralgia
MRI scan ideally for this however if not available trigeminal reflexes may be tested.
What is idiopathic trigeminal neuralgia?
Trigeminal neuralgia with neither electrophysiological tests nor MRI showing significant abnormalities.
What is the diagnostic criteria for idiopathic trigeminal neuralgia?
- Recurrent paroxysms of unilateral facial pain fulfilling criteria for trigeminal neuralgia, either purely paroxysmal or associated with concomitant or continuous/near-continuous pain
- Neither classical trigeminal neuralgia nor secondary trigeminal neuralgia has been confirmed by adequate investigation including electrophysiological tests and MRI.
On examining a patient with suspected trigeminal neuralgia - a good history and examiantion is required for diagnosing. What are some “red flags” if noted in an exam that would require an urgent referral to a specialist?
- Sensory or motor deficits
- Deafness or other ear problems
- optic neuritis
- history of malignancy
- bilateral TN pain
- systemic symptoms eg fever, weight loss
- presentation in patients aged <30 years.
What is the first line of medical management for trigeminal neuralgia?
Carbamazepine - can be described for TN by GDPs working in the NHS or in private practice
Oxcarbazepine if carbamazepine is contr-indicated, not tolerated by the pt, or not providing adequate pain relief.
What is the pharmacology of carbazepine?
Brand name: Tegretol
Anti-convulsant: used for epilepsy and bipolar disorder
Binds to voltage dependent sodium channels therefore inhibit action potential membrane
Metabolised in the liver by enzymes in cytochrome group
Predominantly excreted in urine around 75% with remainder in faeces.
What 2 guidelines would you refer to when prescribing carbamazepine?
- BNF
-SDCEP
What are some considerations and cautions with carbamazepine?
- Do not prescribe for Han Chinese or Thai origin - testing required, increased liklihood of Stevens-Johnson syndrome
- Pregnancy- congenital malfunctions
- Hepatic and renal impairment - caution and monitoring
- Cross sensitivity with anticonvulsants
- Interactions: numerous includes herbal medicines e.g John Warts, alcohol and grapefruits
Patients or their carers must be given advice about how to recognize what disorders when taking carbamazepine?
- Liver
- Skin
- Bone marrow
Immediate medical attention is required if rash, fever, mouth ulcers, bruising or bleeding develop.
What instructions/advice would you give to a patient when prescribing carbamazepine?
Dosing regime:
- 100mg twice daily for 1-3 days
- review
- if necessary increase dose by 100mg every 2 days, introducing lunchtime and afternoon dose if necessary
- therapeutic range from 800-1200 mg per day
- once pain free for 4 weeks trial dose reduction
How often should patients get blood checks if prescribing carbamazepine?
- Not set regime however should have a baseline blood test prior to prescribing or as soon after- should get blood tests weekly for the first 4 weeks or until theyre on a stable dose
- Every 1-3 months after this
Name 4 second line drugs used to treat trigeminal neuralgia that can be used alone or in combination with carbamazepine or oxcarbamazepine.
- Lamotrigine
- Baclofen
- Gabapentin
- Pregabalin
What additional management can GDPs prescribe to help relieve symptoms of trigeminal neuralgia (one can be used as a diagnostic tool).
- Lidocaine 10mg per dose nasal spray for maxillary pain
- Lidocaine 5% ointment to be applied to trigger points as required.
- Lidocaine 2% 1:80,000 adrenaline can be used as infiltration/block to trigger point (diagnostic)
Why might other support such as psychological support be required for patients with trigeminal neuralgia?
- Severe pain
- May be difficult to control
- Side effects of medication
- Negative impacts on activities of daily living
- Negative impact on quality of life
- Depression
- Anxiety
- Suicidal ideation
Name examples of other support you can refer patients to for trigeminal neuralgia.
- Psychological support
- Role of nurse specialists (neurology department)
- National support groups: Trigeminal Neuralgia Association UK
State some indications where surgical management of trigeminal neuralgia would be beneficial for a patient.
- Medical management is ineffective
- Medication not tolerated
- Medication contra-indicated
- Short/no pain free periods
- complications
- adverse impact upon quality of life
What are the 2 different procedures of surgical mangement for trigeminal neuralgia?
- Palliative destructive at the level of the grasserion ganglion. (ablation)
- Posterior cranial fossa surgery (non-ablation)
What is palliative destruction at the level of the grasserian ganglion and name methods used for this.
- Involves controlled damage to the trigeminal ganglion of the peripheral branch of the trigeminal nerve with the aim of relieving pain.
Methods: - radiofrequency thermocoagulation
- gycerol rhizolysis
- balloon compression
-steriotactic radiosurgery - gamma knife
What are methods of posterior cranial fossa surgery?
- microvascular decompression
- partial sensory rhizotomy
- internal neurolysis
What would be the typical surgical management of classical trigeminal neuralgia?
Microvascular decompression as long as not contraindicated
What would be the typical surgical management of idiopathic trigeminal neuralgia?
- neuroablative procedure
What roles are expected of the GDP when presented with a patient of suspected trigeminal neuralgia.
- Diagnose the majority of cases of TN
- To exclude a dental cause or contributing factor in patients symptoms
- Initiate medical management in conjunction with GMP
- Refer
Give a description of glossopharyngeal neuralgia.
A disorder characterised by unlateral brief stabbing pain, abrupt in onset and termination, in the distributions of not only the glossopharyngeal nerve but also of the auricular and pharyngeal branches of the vagus nerve. Pain is experienced in the ear, base of tongue, tonsillar fossa and/or beneath the angle of the jaw. It is commonly provoked by swallowing, talking or coughing and may remit relapse in the fashion of trigeminal neuralgia.
What is the diagnostic criteria of glossopharyngeal neuralgia?
A: Recurring paroxysmal attacks of unilateral pain in the distribution of the glossopharyngeal nerve, and fulfilling criteria B
B: Pain has all of the following characteristics:
- Lasting from a few seconds to 2 minutes
- Severe intensity
- Electric shock like, shooting, stabbing, or sharp in quality
- precipitated by yawning, swallowing, coughing or talking
C: Not better accounted for by another ICHD-3 diagnosis.
Name the 3 subtypes of glossopharyngeal neuralgia.
- Classical
- Secondary
- Idiopathic
What type of imaging would you do for investigation glossopharyngeal neuralgia?
- MRI extending down onto neck