Facial pain

Facial pain:

Pain is a personal experience & communication about it depend on expression & vocabulary of the patient
& interpretation depend on the experience of the clinician .
Pain: is the signal that warn of a threat to the integrity of the organism , so it is serves as useful precaution .
The dentist must recognized patient reaction to pain from perception . Also a detail about the characteristic
,severity , location , duration ,relieving factor together with a thorough clinical examination will lead to perfect diagnosis .
Neuralgia: a pain corresponding to known anatomic distribution of nerve .
Types of verve fibre:
A delta fibre (diameter 1-4 mm , velocity 5-15m/ sec )

C fibre (diameter 0.5-1mm, velocity 0.5-2 m/sec )

Types of neuralgia :
1- primary facial pain
2- symptomatic (secondary) facial pain
3- atypical facial pain

Symptomatic facial pain:

Usually a pathological changes can always be found ( infection ,injury ,scar ,allergy ,new growth)
There are three feature differentiate symptomatic neuralgia from primary neuralgia .
* a mixture of deep & superficial pain which varies in intensity & usually continuous although there are a rare remission &frequent exacerbation
* there are associated objective signs of interruption of continuity of the nerve
* tend gradually to spread to contiguous area


The category of neuralgia (symptomatic ) can
A- Extra cranial :
* localized facial pain : include diseases of the teeth &their supporting structures such as pulpits , periodentitis ,dry socket & ulcer
* diseases of the sinus :
* diseases of the ear
* diseases of the TMJ
* referred & radiating pain
* vascular pain
1- giant cell arteritis : temporal arteritis occur most frequently in older persons usually between the ages of ( 55-80) , it is usually affect women more than men .the pain may be localized first in teeth ,TMJ ,scalp or occipital . nearly one half of the patients complain of tiredness , fatigue and pain on repetitive chewing (jaw claudication -stopping of the mandible )
Usually there is localized inflammation over the swollen ,nodular ,tortures artery . Diagnosis is confirmed
by an arterial biopsy & early diagnosis is essential to prevent sever consequence (blindness).

2- migraine syndrome : pain characterized by the sudden onset of recurrent violent unilateral but sometime bilateral ,paroxysmal attack of cephalgia a companied by visual disturbance , irritability , nosia & vomiting ( preheadache phase ) .There are tow type of migraine , classic {prodromal sensory &visual symptom }& common {no prodromal sensory & visual symptom }
The classic theory is that migraine is caused by vasoconstriction of intracranial vessels followed by vasodilation .Newer research techniques suggest a series of factors, including the triggering of neurons in the midbrain that activate the trigeminal nerve system in the medulla, resulting in the release of neuropeptides such as substance P. These neurotransmitters activate receptors on the cerebral vessel walls, causing vasodilation and vasoconstriction..
The allack usually begins during the second decade of life , there is family history & common in professional person . It may be triggered by foods such as nuts, chocolate, and red wine (which is rich in tyramin which is the precursor of the serotonin ) ; stress ; sleep deprivation; or hunger. Migraine is more common in women.
The headache phase consist of sever pain in the temporal ,frontal &retro-orbital areas.

Treatment
The preheadache phase usually respond to aspirin (300-900mg).paracetamol (1g).with or without antiemetic such as metaclopromide (plasi 100mg) or prochlorperazine (stemetil 5mg).

If migraine attacks occur frequently enough to disturb work & social life , prophylactic drugs are indicated such as propanalol ( inderal 40-80mg tid) , pizotifen (sandomigrain 1.5-3 mg) &antidepressant such as amitriptaline ( tryptizol 25-100 mg) also may be helpful . All these agent have some blocking activity on 5 hydroxy tyramin .


Migraine is treated by giving ergotamine tartarate (cafergot) the maximum daily does (6mg) & up to(10 mg)
per week .
In resistance cases methysergide (1-2mg) is often effective but should be given for course of three months & renal function should be monitored.

3- Horten syndrome , cluster headache ,migranous neuralgia , histamine cephalgia :

The attack occur in cluster & the pain is unilateral ,sever ,knife like which may last from 10 mint to 3 hours .
The recurrent attack of knife like pain effect the temporal area unilaterally passing into the forehead , the side of the head &the shoulder , it may radiate to the mandible but not to the tongue or lip . The intensity of the pain is so sever that during which the patient can not laying down but prefer to seat or walk .

This symptom occur chiefly in male over 40 year of age , it is usually nocturnal in nature .The attack may be precipitated by alcohol beverages or histamine injection , these material induce autonomic effects manifested as nasal congestion , lacrimation & edema of the eyelid &face .

Treatment

Drug which is used in treatment of cluster headache are ergotamine , serotonine antagonist (methysergide which causes retroperitoneal fibrosis ) ,cyproheptadine (periactine ), pizotifen ,amitryptalin , steroid (predinsolone) & indocide .
Inhalation of oxygen may shortened attack of symptom .
Surgical intervention have been tried ,it includes trigeminal sensory rhizotomy, gamma knife radio surgery & decompression of the nervus intermedius .

* nasopharyngeal tumor , retropharyngeal tumor , Trotter,s syndrome:

Pain is experienced in the mandible , side of the tongue , with headache in the affected side , unilateral deafness , deviation of the palate , defective mobility of the soft palate.There are cervical lymphoadinopathy.
It is a carcinoma situated in the lateral pharyngeal fossa , they grow beneath the mucosa &extend below the skull involving the maxillary nerve ( at very early stage ), then other 5th cranial nerve division , then 9th nerve , 10th nerve & upper cervical root . These tumor are highly radiosensitive .

* Frey,s syndrome ( aurico temporal syndrome ):

This is associated with chronic parotitis , &surgery in the parotid gland . The condition is thought to arise fallowing damage to aurico temporal nerve which contain postganglionic parasympathetic fibre from otic ganglion , this damaged fiber become united to the sympathetic nerve from the superior cervical ganglion which supply the sweat gland . clinically there are sweating & flushing of the skin over the distribution of the aurico temporal nerve take place fallowing stimulation of salivary secretion .
.

Tension Headache :

It s the most common type of headache &is often associated with anxiety state ,the pain is constant ,dull felt in frontal &occipital like a tight band around the head . The etiology of this headache is muscle tension .

Diagnosis : history &evidence of anxiety state

Treatment : reassurance & simple analgesia like aspirin & paracetamol

B- Intracranial :

This group consist of tumors including
* those of pituitary
* aneurysms as of the carotid in the cavernous sinus
* brain stem lesions ( multiple sclerosis , vascular malformation )
In such cases pain is intermittent at first & then become sever . later on it is accompanied by other manifestation such as disturbance of vision , restricted movement of the eye balls , defective hearing & cervical lymph node enlargement .
This group also includes cranial base lesion ( injury to the cranium , Paget's disease ) in this group the pain continues &may be bilateral & associated with loss of hearing & disturbance of vision .

Primary neuralgia:

Primary neuralgia is associated with paroxysmal pain ( shock like ,stabbing ) which last seconds with complete or almost complete remission between spasms . The pain is usually so sever that the face is distorted with anguish , the eye fixed , speech & mastication are involuntarily arrested .
There are areas which will precipitate a paroxysmal of pain when superficially stimulated by brushing or touching .Trigger zones are commonly well localized & as they are less likely to be stimulated during sleep , there are nocturnal freedom of pain . Pain is usually limited to the distribution of one nerve or branch of it . Spontaneous remission for months or years are a feature of primary neuralgia .
The cranial nerves in which primary neuralgia are found
* trigeminal nerve ( trigeminal neuralgia – tic douloureux )
* glossopharyngial nerve
* facial (geneculated neuralgia )
* superior laryngeal
* greater auricular
All of these have sensory ganglion , the frequency of occurrence of neuralgia is directly proportion to the size of the ganglia .
Etiology :
There are no known pathology for the primary neuralgia . however there are (2) exception
1-Tic like pain of primary neuralgia may occur in the early stage of progressive lesion which involve , invade or compress the ganglion for example ( tumor , inflammation or aneurysm) but this stage is transient & it soon fallowed by destruction of the ganglionic cell which lead to sensory & motor paralysis .
2-primary neuralgia may persist for a long period with slowly progressive lesion for example ( multiple sclerosis , tapes dorsalis , Paget's disease)
The characteristic of primary neuralgia :
1- nature of the pain is sudden attack of bright pain
2-presence of trigger zone
3- The presence of refractory period , an interval of( 2-3 ) mints must elapse before a further paroxysmal pain can be induced by stimulation of the same area .
4- only temporary relief is obtained by interrupting the peripheral nerve pathway either surgically or by injection of alcohol .
5- destruction of the ganglion itself by hot water or alcohol may effectively cure the pain , but if the destruction is incomplete , regeneration occur &the pain will return .
6- preganglionic root section cure the vast majority of cases , but if the operation is delayed (2-3) years higher station will become unstable by repeated bombardment from the lower cell station & thus preganglionc root section may be ineffective .
7- It has been shown that 10% of patients with trigeminal neuralgia are found with vascular abnormality
8- There are evidence that primary neuralgia are benefited by anticonvulsant drugs , the patient may need (200-1200) mg \ day then dose should reduced gradually until reach the maintaince dose , which is usually range between (400-800) mg \ day.


All primary neuralgia have the above characteristic only the pain distribution &site of trigger zone are different.

Trigeminal neuralgia : Trigeminal neuralgia (TN), also called tic douloureux, is the most common of the cranial neuralgias and chiefly affects individuals older than 50 years of age. When younger individuals are involved, suspicion of a detectable underlying lesion such as a tumor, an aneurysm, or multiple sclerosis must be increased.
It affecting the elderly patient , the maxillary or mandibular division usually involved but rarely the ophthalmic nerve involved . 10% of cases have detectable underlying pathology
The pain may be precipitate by : Touching the trigger zone , washing the face , cold wind blowing on the face, chewing or even talking . The majority of patients with TN present with characteristic clinical features, which include episodes of intense shooting stabbing pain that lasts for a few seconds and then completely disappears. The pain characteristically has an electric shock–like quality and is unilateral except in a small percentage of cases. Treatment: *Carbamazepine (tegretol) in small dose 100-200 mg \ day & gradually increase the dose over 2-3 weeks to 200-400 mg three times daily .
*phenytion 200-400 mg \ day
* clonazepam 1-2 mg three times daily
* topical capsaicin cream
* However permanent cure could be achieved by surgical sectioning of the affected nerve but this should be done in the early stage .
* Injection of pure alcohol in the affected ganglion lead to temporary relief of pain for about 6 months to 2 years
* 5% 0f phenol in glycerin causes partial sensory loss of pain
*electro coagulation of ganglion
*microvasculer decompression
* gamma knife radio surgery

Glossopharyngeal neuralgia :

The trigger zone is either tonsiller fossa , posterior 1\3 of the tongue , side of the soft palate , posterior part of the conches or auditory canal
The pain precipitated by :
Swallowing , yawing , coughing or food touch the tonsiller area

Treatment is similar to that for TN,with a good response to carbamazepine and baclofen. Refractory cases are treated surgically by intracranial or extracranial section of CN IX, microvascular decompression in the posterior cranial fossa,


Post herptic neuralgia :
It is usually felt deep in the ear , it may mistaken with TMJ pain &pain from teeth . However the severity of pain & the association of previous herpes infection could help in diagnosis Pain that persists longer than a month is classified as postherpetic neuralgia . PHN may occur at any age, but the major risk factor is increasing age. The varicella-zoster virus injures the peripheral nerve by demyelination, wallerian degeneration, and sclerosis & changes in the CNS, including atrophy of dorsal horn cells in the spinal cord lead to this neuralgia . the use of antiviral drugs, particularly famciclovir, along with a short course of systemic corticosteroids during the acute phase of the disease may decrease the incidence and severity of PHN

Superior laryngeal neuralgia :

This is usually felt deep in the throat occasionally in the lower part of the face & gum

Great auricular neuralgia :

It is often felt at the angle of the jaw , this may be differentiated from dental pain by giving inferior alveolar nerve block to exclude the dental pain .

Nervous intermedius (geniculate) neuralgia:

Nervous intermedius (geniculate) neuralgia is an uncommon paroxysmal neuralgia of CN VII, characterized by pain in the ear and (less frequently) the anterior tongue or soft palate. The location of pain matches the sensory distribution of this nerve (ie, the external auditory canal and a small area on the soft palate and the posterior auricular region).

Atypical facial pain:

It refers to a mixed group of condition which are defined & diagnosed by exclusion of the other typical patterns of facial pain . it is usually psychogenic & occurs in patients who suffer from depressive reaction , hysteria or schizophrenia .It is more common in women in sixth decade .The pain is deep , poorly localized , vaguely described by the patient & often spread not only to the other side of the face but to the neck & mastoid region
Treatment:
* tricyclic antidepressant ( amitriptyline , nortriptylin