Orofacial pain

Orofacial Painpain

Definition

An unpleasant sensation caused by a noxious stimulus that is mediated only along specific nerve pathway into the central nervous system, where it is interpreted as pain.

Anatomic considerations Pain of the face and

mouth is conducted along the:

Trigeminal nerve ( CN V)

Facial nerve (CN VII ) Glossopharingeal nerve

(CN IX) Vagus (CN X) Cervical nerves 2 & 3

(C2&C3)

Pain classification by origin

Somatic pain Originating from the cells of the organ involved i.e. skin, mucous membrane, bone, joint, muscles, etc…

Neurogenic pain Discomfort resulting within the nervous system. Abnormality in the neural structures. No noxious stimulus

Psychogenic pain Resulting from psychic causes, No noxious stimulus, No abnormality in neural structure

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Somatic pain Neuropathic pain

Superficialsomatic

Deepsomatic

Musculoskeletal Visceral

Episodic Continuous

MuscleTMJ

OsseousPeriodontal

Pulp

Vascular

Neurovascular

Visceral mucosa

Gland, ear, eye

Neuralgia Neuro-vascular

Neuritis

Sympatheticallymaintained

Deafferentn

painSkin Muco-gingival

A- SOMATIC

Somatic pain is usually acute and localized, it also may be :

Superficial from the skin or mucous membrane due to noxious stimuli e.g. thermal or chemical burns, mechanical, ulcerations, infection: ANUG (bacterial) AHGS (viral) Candidiasis (fungal)

Character: Burning, Pricking, Localized.

Deep from bone, muscles, joints and ligaments (Eagle’s syndrome which is due to calcification of the stylohyoid ligament)

Character: dull aching, referred. Inflammatory from collection of infected

fluid e.g. Abscess, infected cyst, pericoronitis.

Character: throbbing with tenderness tends to be localized.

Referred from paraoral structures e.g. maxillary sinus, ear, eyes

Character: deep

B-NEUROGENIC Neuropathy : functional abnormality of

nerves, that may be : Neuritis: inflammatory change of the

nerves. (burning sensation) Neuralgia: pain along the course of the

nerve caused by vascular spasm and CNS diseases

It’s usually poorly localized, chronic, preceded by minor electric shock like pain

CAUSES OF OROFACIAL PAIN

I- Local causes (somatic): Diseases of teeth Diseases of the periodontium Diseases of oral mucosa Disease of jaws Diseases of the antrum Diseases of the salivary glands Diseases of the TMJ Disease of the ears Diseases of the eyes Diseases of the sinuses and

nasopharynx.

II-Neurological causes (Neuropathic)

May be paroxysmal or non-paroxysmal Paroxysmal Trigeminal Neuralgia Glossopharyngeal Neuralgia Gerniculate ganglion Neuralgia Post Herpetic Neuralgia Ramsy Hunt Syndrome Bell’s Palsy Tumors

III-Psychogenic causes No stimuli, No abnormal neural

structures Atypical facial pain Myo-fascial pain dysfunction

syndrome Burning Mouth IV-Vascular Causes Migraine Periodic migrainous neuralgia Vasculitis-Giant cell arteritis Wegner’s disease

Diseases of teeth•Caries, pulpitis •Abscesses•Hypersensitivity•Attrition- Abrasion- Erosions•Fracture•Pericoronitis

Causes of orofacial pain

-Diseases of the periodontium Periodontal Abscess Periodontitis

Occlusal trauma.

Dental impaction.

Cysts & tumours.

Osteitis.

Diseases of the oral mucosa Ulcers Erosions Burns Acute herpetic gingivostomatitis Acute necrotizing ulcerative gingivitis Candidiasis

4-Diseases of the Jaws Dry socket Fractures Osteomyelitis Cysts Tumors

Disease of the sinuses Sinusitis: usually following a cold. Maxillary sinusitis pain is felt in

relation to the upper molars which may be tender to percussion.

Frontal sinusitis Tumors of maxillary sinus

6-Diseases of the salivary glands a- Sialadenitis Due to salivary gland obstruction (stones,

fibrosis) Characterized by pain, swelling associated

usually with eating

b- Acute bacterial parotitis Pain and swelling of the

affected gland, pus discharging from the ductal orifice.

c- Viral conditions (Mumps) Unilateral or bilateral

TMJ pain dysfunction syndrome Aching pain around the joint Clicking of the joint Limitation of mouth opening Arthritis Acute painful spasm of the

facial muscles due to acute inflammatory conditions or tetany

7-Diseases of the TMJ

8-Diseases of the eyes

Conjunctivitis Glaucoma (raised intra ocular

pressure). Errors of refraction Headache and pain in the face

Diseases of the ears (Otitis Media)

Leading to facial pain, also oral diseases can cause pain referred to the ear.

II- Neuropathic (neurologic) orofacial pain

Characterized by paroxysmal pain along the distribution of one or more of cranial nerves.

Described as sharp, stabbing and lancinating, simulating electrical shock, episodic, the pain episodes are often initiated by minor sensory stimuli to the skin or mucous membrane referred to as trigger zone (diagnostic). It affects either deep or superficial structures

1- MAJOR NEURALGIAS•Trigeminal Neuralgia (Tic Douloureux) •Severe, sharp, paroxysmal shocking pain related to the distribution of the trigeminal nerve it may be :•Primary. i.e. idiopathic •Secondary due to trauma or CNS lesions •It affects the maxillary and mandibular divisions of the trigeminal nerve Sex: female > male (2:1).Side: right > left.Site: 2nd & 3rd division CN Age: 60-70 years.

Pathogenesis

Etiology of Idiopathic Trigeminal Neuralgia:

unknown, may be due to: Vascular compression of the

trigeminal ganglion by nearby vessels. (cerebral arteries)

Progressive degeneration of the trigeminal ganglion

Stretching of the nerve over the petrous part of temporal bone which is larger on the right side

Sharp, lancinating, unilateral electric shock like pain, along the course of the nerve.

Lasts from few seconds to few minutes Appears and disappears suddenly Episodic attacks ranges from several per

day to few per year. Between the intervals the patient is

completely free Stimulated by shaving, washing, smoking

and eating After each episode, there is a refractory

period where stimulation of trigger zone will not induce pain

Clinical features

Trigger zone (area) The patient points to the area

(trigger area) with his forefinger without touching it “half an inch finger sign” to avoid initiation of pain.

Diagnosis Local anesthetic block will identify

the specific nerve involved. Neurologic examination to rule out

tumors or multiple sclerosis

Clinical features

2ry Trigeminal Neuralgia

•Results from intracranial trauma, peripheral nerve injury or CNS tumors

Medical management Carbamazepine Baclofen Phenytoin. Surgery: done in cases

refractory to medications. Alcohol injection in nerve

or ganglion Cryosurgery for

peripheral nerve. Sectioning of part of the

nerve

Surgical treatment of TN

Glossopharingeal neuralgia

Clinical features

Rare condition, paroxysmal pain less severe than trigeminal

neuralgia, affecting the Glossopharyngeal nerve. (9th C.N.)

Affects the throat and ears and the post 1/3 of the tongue and pharynx.

Provoked by swallowing or talking, chewing

Post herpetic Neuralgia

Post Herpetic Neuralgia

A complication of HZ (Shingles) which follows it, mainly in elderly patients

Persistence of neuralgic pain after resolution of the rash for weeks or months results from inflammation and fibrosis of the affected nerve, continuous burning severe pain.

2-Bell’s Palsy

Unilateral dysfunction of facial nerve and rapid onset which results in paralysis of facial muscles.

The patient may wake up with fully developed facial palsy

Sometimes preceded by facial pain especially at the angle of the jaw

Unilateral talking & smiling and deviation of the face to the unaffected side

Food retention in upper and lower buccal and labial vestibules

Weakness of buccinator muscle The patient is unable to raise the eye

brow or close the eye unable to whistle or retract the angle of the mouth

Change in facial expressions Drop of the angle of the mouth and

drooling of saliva

Etiology

Idiopathic Trauma Herpes simplex Vasospasm occurs in the bony canal

of the nerve causing ischemia and edema that compresses the nerve decreasing blood supply to the nerve leading to necrosis and fibrosis of the nerve

Clinical features

Treatment

High doses of systemic steroids for 5 days then tailed off in another 5 days

ACTH IM injection for 10 days Analgesics if needed

3- Ramsy Hunt Syndrome Special form of Herpes Zoster

affecting the facial nerve via infection of the Gerniculate ganglion

Starts by prodrome of fever, headache, malaise, ear pain

Appearance of crops of vesicles on the tragus of the ear external auditory meatus and tympanic membrane “Herpetic Oticus”

Deafness, tinnitus and vertigo on the affected side

Unilateral pain affecting the anterior 2/3 of the tongue & soft palateAppearance of vesicles which rupture giving ulcersXerostomia (due to parotid secretion and loss of taste )Loss of taste sensation Facial palsySelf limiting disease resolve within 7-10 days Permanent paralysis may occur

Psychogenic Causes of Facial Pain Atypical Facial Pain (Psychogenic

Facial Pain) "Persistent facial pain that does not have

the characteristics of the neuralgias and is not associated with physical signs

Present daily and persists most of the day.

It is confined at onset to a limited area on one side of the face and may spread to the upper and lower jaws or other areas of the face or neck.

It is deep and poorly localized.

Clinical picture

It affects females more than males 19:1.

Its common sites are the maxilla and the tongue.

Character of pain: Chronic, intermittent dull aching, and poorly localized so that the patient is unable to define location of pain.

It gets worse with fatigue and stress, but doesn't interfere with eating or sleeping.Responds poorly to analgesics.Emotional breakdown, tears, hysteria are common.

Diagnosis It is diagnosed by exclusion of other causes

of Orofacial pain. 1. Case history 2.Clinical examination 3.Diagnostic aids Vitality test and radiographs Through examination of the nose and

pharynx. Oral examination. Careful examination of the cranial nerves and

parotid gland.

Pain of Musculoskeletal Origin

1. Myo-facial pain dysfunction SyndromeIt is a chronic disorder characterized by unilateral dull pain in front of the ear that is worst on awakening, clicking and limitation of mouth opening in absence of pathological abnormality in TMJ

Etiology1. Muscle over-

extension:Due to intermaxillary space <e.g. high filling, prosthetic restoration or denture>.

EtiologyMuscle over-

contraction:Due to over-closure of mouth <e.g. bilateral loss of posterior teeth, improper prosthetic restoration>.

EtiologyBilateral loss of posterior

teeth or improper prosthetic appliance leads to over closure of the mouth and muscle over contraction muscle fatigue

Clinical features

Unilateral dull pain in the ear or preauricular area which is worse on awakening, and there may be vague pain affecting the whole side of the face.Tenderness of muscles of mastication on palpation.Limitation or deviation of mandible on opening to the affected side.Clicking in TMJ.

Radiating pain to masseter muscle, occipitally, cervically to the neck or to the angle of the mandibleTrismus (locking or inability to open the mouth).Patients frequently grind or clench their teeth or develop other Para functional habits e.g. pencil chewing and so on clinical examination there are:Wear facets on teeth.Ridging of tongue margins and buccal mucosa at the occlusal line.

Trigger point

It is an area of muscle that is tender on palpation it may occur in:•Muscles of mastication. •Cervical muscle (sterno-mastoid).

Management of MFPDS1. Elimination of cause e.g.:

high filling occlusal adjustments.

2. Occlusal splints (Bite raiser – night guard) if no local factor can be detected.

3. Patient reassurance .

Vascular Lesions

Migraine Migraine is a recurrent headache. It is due to arterial dilatation. Attacks

are precipitated by alcohol, drugs as nitroglycerin, stress & environmental factors e.g smoke & noise .

It is characterized by unilateral headache, nausea, vomiting & photophobia .

It is treated by drugs & avoidance of precipitating factors.

Periodic migranous neuralgia

Periodic migranous neuralgia

It is usually idiopathic, less common than migraine & it causes unilateral facial pain

-Giant cell arteritis It is an immunologically mediated

disease characterized by inflammation of the wall of medium size arteries, with prominent giant cells, there is obliteration of the artery lumen and ischemia of the part supplied by involved artery.

Giant cell arteritis may affect the craniofacial region e.g. temporal arteritis.

Temporal arteritis Is characterized by unilateral or

bilateral deep throbbing pain of acute onset over the temporal region and prominent tortuous tender temporal artery.

Pain may radiate to mandible or maxilla.

Definitive diagnosis is based on temporal artery biopsy giant cell arteritis.

Treatment: corticosteroids.

Temporal arteritis

Other Causes Of Headache & Facial Pain

(Miscellaneous Causes) Orofacial pain may be referred from the

chest as in ischemic heart disease and lung cancer .

Raised intracranial pressure may cause headache. It may be due to malignant hypertension, tumour or hematoma .

Diseases of the skull such as bone metastasis or Paget's disease may cause headache .

Trotter's syndrome: it is orofacial pain caused by carcinoma affecting lateral wall of pharynx.

Atypical Odontalgia

Also called Idiopathic, Phantom tooth pain

Clinical features Tooth ache with no detectable cause Pain is unaffected by endodontic

therapy or even extraction of the tooth Persistent pain in a single tooth or a

group of teeth that exhibits no abnormality on percussion or pulp testing