1. Oral Medicine & Radiology
OROFACIAL PAIN-1
DEFINITION
According to International association for the study of pain (IASP) pain is defined as :- “An unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage.”
Dr.S.Karthiga Kannan
Porfessor
Oral Medicine & Radiology

2. SPECIFIC LEARNING OBJECTIVES
To know the pathophysiology of orofacial pain
To know the classification of orofacial pain
To know the clinical characteristics and treatment of
Trigeminal Neuralgia (TN)
Glossopharyngeal Neuralgia (GN)
Post Herpetic Neuralgia (PHN)

3. PAIN PATHWAYS

4. CLASSIFICATION OF OROFACIAL PAIN
CHORNIC OROFACIAL PAIN
LOCAL DISEASES
☞Musculoskeletal diseases Temporomandibular disorder(TMD) Myofacial pain dysfunction syndrome (MPDS) Eagle’s syndrome ☞ Vascular diseases Migraine Cluster headach Temporal or Giant cell arteritis ☞ Neurologic disorders Trigeminal neuralgia Glossopharyngeal neuralgia Post herpetic neuralgia ☞ Psychogenic Pain Atypical facial pain Burning mouth syndrome Atypical odontalgia
☞ Dental causes Pulpal Pulpitis Dentin hypersensitivity Cracked tooth syndrome Apical periodontitis Periapical Abcess Gingivitis/Periodontitis ANUG Pericoronitis /pericoronal abcess Oral ulcers Oral Cancers ☞ ENT diseases like sinusitis, otitis media Pharygitis, ☞ Eye diseases – Conjunctivitis

5. Episodic pain ☛ Trigeminal neuralgia ☛ Glossopharyngeal neuralgia ☛ Post-herpetic neuralgia ☛ Giant cell arteritis Constant pain ☛ Burning mouth syndrome ☛ Atypical facial pain ☛ Atypical odontalgia ☛ Temporomandibular joint dysfunction
Pattern of pain
Loss of function or sensation
☛ Facial nerve palsy
☛ Trigeminal nerve paresthesia

7. Category rating scale
Numeric rating scale

8. TRIGEMINAL NEURALGIA (TN)
Synonym –
☛ Tic douloureux, ☛ Fothergill’s neuralgia
Types
☛ Classical TN (85%) – caused by compression of sensory root by vascular anurysm.
☛ Secondary TN – caused by tumors, viralinfection, trauma, and multiple sclerosis.
☛ Is the most common of the cranial neuralgias
☛ Age predilection - older than years of age.

9. CLINICAL FEATURES
☛ NATURE – Unilateral, Paroxysmal (occurs in episodes) awakes from sleep. ☛ QUALITY – Sharp, stabbing,electric shock like, piercing. ☛ INTESITY – Severe ☛ AGGRAVATING FACTORS – shaving, eating, washing face, speaking, exposure to wind. ☛ DURATION – from seconds to 2 minutes. ☛ SITE – Maillary, mandibular, Opthalmic dermatome in decending order, usually right side.

10. Clinical features
☛ TRIGGER ZONE - Pain in TN is precipitated by a light touch on a “trigger zone”(Allodynia) present on the skin or mucosa within the distribution of the involved nerve branch.
☛ Common sites for trigger zones include the nasolabial fold and the corner of the lip.
☛ REFRACTORY PERIOD - Just after an attack, touching the trigger zone will not precipitate pain.
☛ PAIN BEHAVIOR – spasm of ipsilateral facial muscles, Patient protects / cover that area.

11. DIFFERENTIAL DIAGNOSIS
INVESTIGATIONS
☛ Cracked tooth Syndrome
☛ TN pain will be triggered by touching the soft tissue around the trigger zone, whereas pressure on the tooth is required to cause pain from a cracked tooth.
☛Local anesthetic blocks, which temporarily eliminate the trigger zone, may also be helpful in diagnosis. ☛ CT scan,MRI of the brain is indicated to rule out tumors, multiple sclerosis. ☛ Magnetic resonance tomographic angiography (MRTA) for vascular lesions.

12. MANAGEMENT OF TN MEDICAL SURGICAL
☛ Carbamazepine – mg / twice a day can be increased slowly
☛ Baclofen – 5-10mg thrice a day
☛ Oxcarbamazepine – 300mg/ thrice a day
☛ Gabapentin – mg/twice a day
☛ Phenytoin – mg /day
☛ Lamotrigine 25mg/1-2 time perday
☛ Pheripheral Neurectomy ☛ Percutaneous Trigeminal Rhizotomy – TN ganglion level -Glycerol injection -Ballon compression -Radiofrequency rhizolysis ☛ Microvascular decompression (MVD) – Brainstem level ☛ Gamma knife stereotactic radiosurgery (GKS) – Gy radiation.

13. GLOSSOPHARYNGEAL NEURALGIA (GN)
☛ ETIOLOGY – compression of nerve root by blood vessel or anurysm. ☛ TYPES ☛Pharyngeal GN Pharynx, posterior tongue are involved and radiate to ear, eyes, nose, maxilla, shoulder and even tip of tongue. ☛Tymphanic GN Ear pain radiating to pharynx ☛ NATURE OF PAIN -Paroxysmal, unilateral, moderate to severe pain ☛ QUALITY – Sharp, stabbing, shooting or lancinating. ☛ DURATION – Fraction of second to 2 minutes ☛ FREQUENCY – 5-12 every hour and may occur in cluster lasting for weeks to months.

14. ☛ TRIGGER POINTS - Tonsillar region, posterior pharynx
☛ TRIGGER POINTS - Tonsillar region, posterior pharynx. ☛ AGGRAVATING FACTORS – swallowing, chewing, talking, coughing and yawning, sneezing and rubbing ear. ☛ COMPLICATIONS – GN may induce uncontrollable coughing, seizures, and cardiac arrythmias, bradycardia and syncope. ☛ TREATMENT ♐MEDICAL - Carbamazepin, baclofen, oxcarbazepin, gabapentin, lamotrigine and phenytoin. ♐SURGICAL – Microvacular decompression and Gamma knife stereotactic radiosurgery

15. POST HERPETIC NEURALGIA (PHN)
☛ PHN- Pain of herpes zoster that persists three or more months.
☛ AGE – common in > 50 yrs
☛ SITE % - Opthalmic nerve is commonly affected.
☛NATURE OF PAIN - Burning constant pain & superimposed flashes of pain
☛QUALITY – burning, sharp, shooting, throbbing , stabbing.
☛AGGRAVATING FACTOR – Hypo pigmented scar acts as trigger points – Allodynia.
☛ COMPLICATION - Paresthesia- loss of sensation

16. MANAGEMENT
☛ Prevention by use of varicella zoster vaccine ☛ For those with active Herpes Zoster use of antiviral drugs early in the course of the disease ☛ Acyclovir: 800 mg 5 times / day for 2 Weeks. ☛ Famcyclovir 250 mg 3 times a day ☛ Systemic Corticosteroid Prednisolone - 60 mg / day for 1st week 30mg / day for 2nd week and 15mg / day for 3rd week Treatment should be started within 10days and continued for three weeks
For those who develop PHN
☛ Topical therapy such as lidocaine.
☛ Topical application of Capsaicin , a selective c-fiber neurotoxin that deplete the substance P
☛ Tricyclic antidepressant therapy Amitriptyline mg daily divided doses.
☛ Gabapentin mg twice daily
☛ TENS - Trans Cutaneous Electrical Nerve Stimulation
☛ Opioids, Tramadol

17. Glossopharyngeal neuralgia Postherpetic neuralgia
CLINICAL CHARARECTERISTICS
Trigeminal neuralgia
Glossopharyngeal neuralgia
Postherpetic neuralgia
1.Site
Face
Throat, tonsillar region
Forehead,eyes –opthalmic dermatome
2.Nature
Sharp, stabbing, shooting
Burning constant pain & superimposed flashes of pain
3.Severity
Worst pain experienced
Moderate to Severe
4.Initiating factors
Light touch, washing
Swallowing, chewing
Allodynia – light touch
5.Relieving factors
None

18. Thank you