▼ 23 N D

Transcription

▼ 23 N D

23
▼
NEUROMUSCULAR DISEASES
KATHARINE N. CIARROCCA, DMD, MSED
MARTIN S. GREENBERG, DDS
ADI GARFUNKEL, DDS
▼ CEREBROVASCULAR DISEASE
▼ CEREBRAL PALSY
Cerebrovascular Accident or Stroke
Transient Ischemic Attack
Oral Health Considerations
Clinical Manifestations
Treatment
▼ CAVERNOUS SINUS THROMBOSIS
▼ BELL’S PALSY
Treatment
▼ MULTIPLE SCLEROSIS
Etiology and Epidemiology
Diagnosis
Treatment
▼ GUILLAIN-BARRÉ SYNDROME
Treatment and Prognosis
▼ MYASTHENIA GRAVIS
▼ AMYOTROPHIC LATERAL SCLEROSIS
Treatment
Treatment
▼ MUSCULAR DYSTROPHY
▼ PARKINSONISM: PARKINSON’S DISEASE
(PARALYSIS AGITANS)
Treatment
Etiology and Pathogenesis
Treatment
▼ EPILEPSY
Classification of Seizures
Treatment of Seizures
▼ HUNTINGTON’S DISEASE (HUNTINGTON’S
CHOREA)
Treatment
592
593
Neuromuscular Disease
Diseases that affect both nerve and muscle tissue encompass
a broad range of symptoms that often have profound implications for the successful management of the dental patient.
The diseases discussed in this chapter include only those that
affect the orofacial region or that have a significant effect on
dental practice.
▼ CEREBROVASCULAR DISEASE
Cerebrovascular disease includes all disorders that cause damage to the blood vessels supplying the brain, thereby producing
neurologic damage. “Stroke” and “cerebrovascular accident”
(CVA) are terms used to describe an acute neurologic injury
resulting from a severe interruption in the flow of blood to the
brain. Complete cessation of the flow may render an irreversible
cerebral infarct within a period of 3 or 4 minutes. General
symptoms following stroke include variable motor paralysis,
sensory loss, visual difficulties, and speech impairment.
Epidemiologic studies have shown that cerebrovascular disease is the third leading cause of death in developed countries,
with a prevalence of 0.8% of the total population affected. It is
estimated that more than 400,000 individuals are affected by
stroke annually in the United States. The majority of patients
are over 60 years of age. The overall mortality rate following
stroke is 25% in the first month and 50% within 5 years.
Cerebrovascular Accident or Stroke
Approximately 80% of strokes are associated with the development of atherosclerosis leading to cerebral ischemia and
infarction. The remaining 20% of cases are caused by cerebral
hemorrhage.1 Deposition of atheromas in artery walls predisposes a patient to the development of thrombosis and embolus formation, which results in infarction of the area of the
brain supplied by the occluded vessel. A thrombus is a clot in
the vasculature that forms from the constituents of blood and
may be occlusive or attached to a vessel without obstructing the
lumen. An embolus is a clot, composed of a detached thrombus, mass of bacteria, or other foreign body, that originates
from a distant site in the body and occludes a vessel. Atheromas
commonly develop in the branching portions of the arterial
system, particularly at the origin of the internal carotid artery.
Additional sites of thrombus formation associated with stroke
include the vertebral, basilar, and middle cerebral arteries.
LACUNAR INFARCTION
Lacunar infarcts are small lesions (usually < 5 mm in diameter) that occur in the distribution of the short penetrating
arterioles in the basal ganglia, circle of Willis, pons, cerebellum,
anterior limb of the internal capsule, and (less commonly)
deep cerebral white matter. Lacunar infarcts are associated
with poorly controlled hypertension or diabetes. Symptoms
usually include unilateral motor or sensory deficit without
visual field deficit or disturbance of consciousness or language.
The neurologic deficit produced by the lacunar infarct may
progress over 24 to 36 hours before stabilizing; however, the
prognosis for recovery from the deficit produced by a lacunar
infarct is usually good, with partial or complete resolution
occurring over the following 4 to 6 weeks in many instances.
CEREBRAL INFARCTION
A cerebral infarction occurs when there is ischemia and necrosis of an area of the brain after a reduction of blood supply to
a level below the level necessary for cell survival. The two major
causes of cerebral infarction are thrombosis and embolism,
often the result of atherosclerosis. Emboli frequently originate
in atherosclerotic plaques in any vessel of the neck, such as the
carotid artery. The emboli break off, pass through the vasculature, and ultimately occlude an intracranial vessel, thus causing a stroke. Thrombosis of an intracranial vessel may also
lead to stroke.
The resulting deficit depends on the particular vessel
involved and the extent of any collateral circulation. Carotid
artery atherosclerosis, for example, will most frequently cause
infarction in the region of the brain supplied by the middle
cerebral artery. Occlusion of this artery results in contralateral
signs such as facial weakness, head and eye deviation, flaccid
hemiparesis or hemiplegia, and hemisensory loss.
Thromboembolic cerebral infarction also occurs as a complication of other diseases. Many of the emboli that occlude
intracranial vessels arise from thrombi that have formed in the
left side of the heart. Emboli originating from the heart are
often the result of thrombus formation after acute myocardial
infarction, chronic atrial fibrillation, or rheumatic heart disease. Hypertension is an important risk factor in the development of thrombosis, particularly at the carotid bifurcation.
Treatment of severe hypertension is essential for the prevention of stroke since it is estimated that the risk of stroke
increases sevenfold in individuals with uncontrolled hypertension. Septic emboli may result from bacterial endocarditis,
particularly when the mitral valve is involved.
Other causes of ischemia and infarction of the brain
include decreased blood flow secondary to sudden severe
hypotension, acute hypertension causing spasm of the cerebral
vessels, and hematologic abnormalities such as thrombocytosis, anemia, and cavernous sinus thrombosis.
CEREBRAL HEMORRHAGE
Hemorrhage of intracranial vessels may also cause stroke.
The two most common reasons for hemorrhage are (1) rupture of an aneurysm and (2) an arteriovenous malformation
(AVM) that hemorrhages spontaneously, often secondary
to hypertension or following the administration of anticoagulant medication.
The majority of cases are aneurysmal. Aneurysms are
localized dilations of arteries, caused by structural weakness
of vessel walls. True aneurysms are found in arteries with
normal wall structures that have been damaged by conditions
such as atherosclerosis, mycotic infections, and syphilis. False
aneurysms occur after the traumatic rupture of arteries and
their subsequent repair by fibrous tissue. The size of the
aneurysm is important in determining its tendency to rupture, a tendency that is aggravated by smoking, alcohol con-
594
sumption, or strenuous exercise. The sequelae of hemorrhage from ruptured aneurysms are usually sudden and
severe, ranging from seizures and coma to death. In the acute
situation, it is vital to distinguish ischemic stroke from hemorrhagic stroke by the use of computed tomography (CT)
without contrast.
CLINICAL MANIFESTATIONS AND TREATMENT OF STROKE
Strokes due to ischemia may be classified clinically either as a
stroke in evolution or as a completed stroke. “Stroke in evolution” is a descriptive term used to indicate a condition in which
symptoms associated with cerebral ischemia become progressively worse while the patient is under observation. The etiology is often related to the propagation of a thrombus in the
carotid artery. Treatment should be immediate and consists of
controlling severe hypertension (> 185/110). However, decreasing milder hypertension may actually increase infarction in a
patient with acute thrombosis. The use of thrombolytic agents
such as recombinant tissue plasminogen activator may decrease
the severity of a stroke in carefully selected patients, but
intracranial hemorrhage complicates this therapy. This regimen
attempts to minimize the extent of permanent neurologic damage due to ischemia. Anticoagulants (such as heparin) or
antiplatelet therapy with aspirin may also be used. Daily low
doses of aspirin are recommended to decrease the incidence of
thromboembolic strokes.2
A completed stroke caused by a thrombus often evolves
slowly, and the full neurologic picture may take hours or
even days to emerge. This clinical picture commonly includes
hemiplegia, aphasia, and cranial nerve defects involving
nerves V, VII, IX, and X. Symptoms of stroke caused by an
embolus develop suddenly. It is not preceded by transient
ischemic attacks (see below); rather, the stroke itself evolves
rapidly because the clot originates elsewhere and suddenly
blocks a cerebral vessel. Whatever the cause of the neurologic
damage, the resultant infarct may enlarge for a period of 4 to
5 days because of cerebral edema. Repair is dependent on
good collateral circulation and is accomplished by the formation of fibrogliotic scar tissue. Significant clinical
improvement may occur after 3 weeks, when the cerebral
edema has subsided.3
After a completed stroke, treatment focuses on the prevention of further neurologic damage, through the reduction
of underlying risk factors and by rehabilitation procedures,
including speech and physical therapy.
An intracranial hemorrhage should also be treated as a
medical emergency of airway maintenance and requires the
transfer of the patient to an intensive care unit with close monitoring. Blood pressure should be maintained in the 140/90
range. Fluid intake should be limited. Treatment with fibrinolytic drugs such as tranexamic acid might reduce new
episodes of bleeding. Cerebral edema may be treated with dexamethasone and diuretics. The surgical treatment of a hemorrhaging aneurysm or an AVM consists of closing off the
blood vessels that supply the area and removing the abnormality. This procedure has generally yielded high success rates.
Principles of Medicine
Transient Ischemic Attack
A transient ischemic attack (TIA) is a sudden but reversible
neurologic deficit that lasts from a few minutes to 24 hours.
Approximately 30% of individuals with a history of TIA experience a completed stroke within a 5-year period.4 The frequency of TIAs varies considerably, ranging from multiple
daily attacks over an extended period to only a few attacks
before a true stroke occurs.
ETIOLOGY
An important cause of transient cerebral ischemia is embolization. In many patients who experience these attacks, a source
is readily apparent in the heart or a major extracranial artery
to the head, and emboli sometimes are visible in the retinal
arteries. Cardiac causes of embolic ischemic attacks include
rheumatic heart disease, mitral valve disease, cardiac arrhythmia, infective endocarditis, and mural thrombi complicating
myocardial infarction. An ulcerated plaque on a major artery
to the brain may also serve as a source of emboli. Hematologic
causes of ischemic attacks include polycythemia, sickle cell
disease, and hyperviscosity syndromes.
CLINICAL MANIFESTATIONS
The symptoms of TIAs vary markedly among patients; however, the symptoms in a given individual tend to be constant
in type. Onset is abrupt and without warning, and recovery
usually occurs rapidly, often within a few minutes. During the
attack, a wide variety of neurologic signs and symptoms can
develop, depending on which site of the brain is affected by
ischemia. Repeated short periods of arm and hand weakness
are associated with focal ischemia in the contralateral frontal
lobe. If the vertebrobasilar arterial system is involved, short
episodes of dizziness, diplopia, dysarthria, facial paresthesia,
and headache are common symptoms.
TREATMENT
Treatment of TIAs should be initiated as soon as the diagnosis is established and should be directed toward the correction
of the immediate pathologic problem (eg, embolism). In addition, measures to control the primary underlying problem (eg,
hypertension or coagulopathy) should be undertaken.
Anticoagulant therapy with either heparin or coumadin is
often used, but there is little convincing evidence that anticoagulant drugs are of value. Treatment with aspirin, however,
significantly reduces the frequency of TIAs and the incidence
of stroke in high-risk patients. Dipyridamole is also used but
is not as effective; when added to aspirin, it offers no advantage over the use of aspirin alone for stroke prevention.5
Vascular surgical endarterectomy is now often used as an
alternative treatment of TIAs caused by carotid stenosis. After
surgery, a reduction in the frequency of TIAs and their progression to stroke has been observed.4
As the first line of medical management of stroke patients is
often anticoagulant therapy, the patient may have a predis-
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Neuromuscular Diseases
position to excessive bleeding. A thorough medical history
with an accurate medication list that includes dosages is essential. In addition, it may be necessary to confer with the
patient’s physician to obtain current coagulation values (ie,
PT, INR) so as to ensure that the patient is stable for more
invasive dental treatment.
Xerostomia is a common side effect of the medications
used in the management of cerebrovascular disease and related
disease processes. Patients who are thus affected can then be
susceptible to a higher caries rate. Meticulous oral hygiene,
more frequent recalls, saliva substitutes, and fluoride application can aid in the maintenance of the dentition.6
Stroke patients can also have physical disabilities, which
can affect the orofacial area and can alter the provision of
dental care. Patients with hemiplegia or hemiparesis may
need additional help in home care. Patients with weakness in
the muscles of the orofacial area may have poor control of
oral secretions, a reduced gag reflex, and changes in their
ability to masticate, leading to poor nutrition. Patients with
apraxia affecting the orofacial region may have impaired voluntary movements, such as protruding the tongue, expectorating, and lip puckering.
In general, dental treatment should not present major
problems for most poststroke patients. Careful history taking,
checking of blood pressure prior to treatment, avoidance of
lengthy appointments, and general reassurance are all important factors in the provision of dental treatment for patients
with a history of stroke.
▼ CAVERNOUS SINUS THROMBOSIS
Cavernous sinus thrombosis, usually secondary to dental,
nasal, or ocular infections, is a rare but severe complication
because of its possible fatal outcome. Infections of the maxillary dentition may spread to the cavernous sinus through
openings in the cranial bones or through emissary veins connecting the extra- and intracranial systems. Venous propagation begins with the facial vein and proceeds through the ophthalmic vein, which is an affluent of the cavernous sinus. In
most cases, patients experience rapid swelling of the face and
eyelids. The classic neurologic signs of acute cavernous sinus
thrombosis are exophthalmos, periorbital edema, retinal vein
thrombosis, and involvement of the ophthalmic division of the
trigeminal nerve and trochlear and abducent nerves, leading to
ptosis, dilated pupils, and lack of corneal reflexes. Treatment
consists of immediate antibiotic therapy and the removal of
the source of infection whenever possible.
▼ MULTIPLE SCLEROSIS
Multiple sclerosis (MS) is a chronic neurologic disease associated with the demyelination of axons within the central nervous system. The disease occurs more frequently among
women. The average age of onset is during the fourth decade
of life, but MS may occur at any age. The disease presents in
the form of recurrent attacks; in some cases, the attacks are
years apart. The most common symptoms following an acute
exacerbation include impairment of vision, muscular incoordination, and bladder dysfunction. The general histologic features are multiple disseminated plaques or areas of demyelination within the central nervous system.
Etiology and Epidemiology
The specific etiology of MS has not been clearly determined.
An immunologic basis is strongly suggested by the presence of
activated T lymphocytes and autoantibodies to glycoproteins
detected in MS lesions. In addition, it is considered probable
that both genetic and environmental factors are involved, with
infection as the major environmental agent. Both viral and
bacterial infections can initiate or precipitate attacks of MS.
Evidence that implicates certain viruses in the initiation of the
disease has been documented; increased antibody titers against
measles virus, rubella virus, mumps virus, Epstein-Barr virus,
herpes simplex viruses 1 and 2, and human herpesvirus 6
(HHV-6) have been found in the cerebrospinal fluid and
serum. To date, none of these viruses has been isolated from
the lesions of MS, and no specific relationship between MS and
a specific microorganism has been proven. Further data supportive of an infectious etiology for MS include the observation that MS has occurred in clusters in specific populations,
the prime example being the increased incidence of MS in the
population of the Faroe Islands following foreign troop occupation during World War II.7
Genetic influences also appear to play a significant role in
the development of MS. Studies of identical twins have shown
that if one twin suffers from MS, there is a 26% chance that the
other twin will also be affected by the disease. A preponderance
of specific human leukocyte antigen (HLA) types has also been
noted in MS patients.8,9
The most accepted general finding related to the etiology
of MS is the fact that disease prevalence increases with distance
from the equator; for example, MS is most common in northern Europe, Canada, and New Zealand. There are no obvious
reasons for this geographic difference in disease prevalence.
The clinical signs and symptoms of MS depend on the site of
the demyelinating lesion. The lesions may occur almost anywhere in the central nervous system, but they have a predilection for certain areas. More than 60% of individuals with MS
have visual disturbances caused by demyelinating lesions of
the second cranial nerve. The loss of vision usually occurs
over a period of several days, with partial recovery within 1
month. Other ophthalmic symptoms include “color blindness” and diplopia caused by involvement of the third, fourth,
and sixth cranial nerves. Uhthoff ’s sign, found in MS, is characterized by rapid vision loss following a body temperature
increase that is associated with strenuous exercise. Another
important sign of ocular disturbance associated with MS is
Marcus Gunn’s pupillary sign, which can be elicited in
patients with unilateral optic neuritis in the following manner: a bright light is shone into each eye separately; when this
596
light is moved from the normal to the affected eye, the pupil
of the latter dilates rather than constricts.
Weakness or paresthesia of the extremities, with an increase
in the deep tendon reflexes, is another common early finding
in cases of MS. An important feature of motor nerve function
in MS patients is the relative fluctuation of symptoms on a
daily basis. These symptoms may remit for long periods and
then suddenly reverse, leading to paraplegia. Other common
signs of the disease include bladder dysfunction, euphoria,
ataxia, vertigo, and generalized incoordination.
The majority of cases of MS are chronic and are characterized by exacerbations and remissions over a period of many
years. During acute episodes, severe neurologic involvement is
evident. This slowly resolves, but some permanent neurologic
involvement remains after each episode. The extent and severity of the permanent involvement varies considerably from
patient to patient. In mild cases, little permanent effect is
noted, and patients may have a normal life span. In severe
acute cases, total paralysis may occur within months. Overall,
it has been found that approximately 70% of patients with
MS live for more than 25 years after the onset of the disease.
Diagnosis
The diagnosis of MS is clinical and is based on the age of the
patient, the presence of neurologic signs that cannot be
explained by a single lesion, the progressive nature of the disease, and a history of exacerbations and remissions. There are
no definitive laboratory tests for MS, but demyelinating
changes can be seen on magnetic resonance imaging (MRI) in
more than 90% of cases.4 The presence of increased
immunoglobulins (specifically immunoglobulin G [IgG]) in
the cerebrospinal fluid without infection is another diagnostic indicator of the disease.
Treatment
Evidence suggests that high doses of intravenous corticosteroids may arrest the progress of MS; about 85% of patients
with relapsing-remitting MS show objective signs of neurologic improvement during treatment with intravenous corticosteroids. Long-term treatment with immunosuppressants
may reduce the frequency of relapse in patients with MS.
Azathioprine is probably the safest drug in this category and
has reduced relapse to 70% of study patients in 3 years, compared to 80% of patients in the placebo group. Administration
of methotrexate appears to be the best therapy for slowing
deterioration in patients with chronic progressive MS. The use
of interferon-γ-1b and -1a has shown promise; both have been
shown to reduce clinical attacks and lesions detectable by contrast-enhanced MRI by approximately 30% when compared to
placebo. Other nonpharmacologic measures, such as total lymphoid irradiation, plasmapheresis, and immunoglobulin therapy, have had marginal benefit.10
Certain clinical manifestations of MS affect the orofacial
region; three are of particular interest to the dentist: trigem-
inal neuralgia, sensory neuropathy of the trigeminal nerve,
and facial palsy.11
Trigeminal neuralgia (TGN) is present in about 2% of
cases of MS and is an initial manifestation in 0.3% of cases.12
In those cases in which MS is associated with TGN, there
appears to be an earlier age of onset, and symptoms are commonly bilateral. Pain is normally severe and lancinating, but
trigger zones may be absent. In time, the pain often becomes
less severe but more continuous. Effective drug therapy
includes the use of carbamazepine, baclofen, gabapentin, or
phenytoin. When medication proves inadequate, thermocoagulation, surgical sectioning of the nerve, or alcohol injection
may be considered.
Sensory neuropathy secondary to MS can be progressive
and difficult to diagnosis. It most often affects the second and
third divisions of the trigeminal nerve, has a sudden onset, and
is painful. Neuropathy to the mental nerve can cause numbness of the lower lip and chin.
Facial paralysis appears later in the course of the disease. It
may be difficult to distinguish between the paralysis caused by
MS and that due to Bell’s palsy, but up to 24% of MS sufferers
may experience facial paralysis.11
▼ AMYOTROPHIC LATERAL
SCLEROSIS
Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig
disease and motor neuron disease, belongs to a group of
degenerative diseases affecting both the upper and the lower
motor neurons of the central nervous system. The principal
symptoms are weakness and wasting, which normally begin in
the upper extremities and are invariably unilateral at onset.
The estimated prevalence of ALS in the United States is
reported as 2 to 7 per 100,000 persons, with slightly more
males than females affected. The average age of onset is
between the fourth and sixth decades of life. The etiology is
unknown, although the disease is familial in 10% of cases
when it is inherited as an autosomal dominant or autosomal
recessive trait.1 The degenerative changes of ALS can be seen
in the corticospinal tracts (upper motor neurons), the motor
cells of the brainstem, and the anterior horn cells of the spinal
cord (lower motor neurons).
In the most typical form of ALS, stiffness of the fingers, awkwardness in tasks requiring fine finger movements, and slight
weakness or wasting of the hand muscles are the first indications of the disease. Cramping and fasciculation of the muscles of the forearm, upper arm, and shoulder girdle also appear.
Before long, the triad of atrophic weakness of the hands and
forearms, light spasticity of the arms and legs, and generalized
hyperreflexia (in the absence of sensory changes) leaves little
doubt as to the diagnosis. After some time, the disease affects
all regions, including the muscles of mastication, facial expression, and tongue, leading to difficulties in mastication and
speech. Dysfunction of the temporomandibular joint and the
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development of malocclusion may also occur as the disease
progresses. Aspiration pneumonia is the cause of death in most
patients with ALS.
Treatment
There is no effective treatment for this disease, and the course
is one of progressive deterioration, with a mean survival of 3
years. Ceftriaxone, gabapentin, guanidine hydrochloride, gangliosides, interferons, and cyclophosphamide are a few of the
long list of agents that have all proven to be ineffective. Only
supportive measures can be used.13
Muscles of the orofacial area can be affected by the disease
process of ALS. The most striking physical effect of ALS relates
to the declining function of the muscles used for breathing. As
the patient may not be able to cough or clear the throat, a
reclining position for dental treatment is contraindicated due
to the increased risk of aspiration.14
In addition, a hyperactive gag reflex can pose a problem.
Although it provides assurance that no dental debris will be
aspirated, every effort must be made not to induce gagging or
vomiting. Topical anesthetics should be avoided, patients
should be nil per os (NPO) for 12 hours prior to treatment,
and the dentist should avoid contact with soft-tissue areas that
may induce gagging. Topical fluoride may also induce nausea.
Finally, patients with ALS may have difficulty with oral
hygiene. Not only will these patients be challenged with physical disabilities that limit their effectiveness in maintaining
oral hygiene, they are also faced with a loss of the natural clearing ability of the oral cavity because of decreased muscular
activity of the tongue and the perioral musculature.14
Mechanical toothbrushes, fluoride rinses, and more frequent
periodontal recall may benefit these patients greatly.
▼ PARKINSONISM: PARKINSON’S DISEASE (PARALYSIS AGITANS)
Parkinsonism is a neurodegenerative disorder characterized by
rigidity, tremors, bradykinesis, and impaired postural reflexes.
The most common form of parkinsonism is Parksinson’s disease (paralysis agitans), but parkinsonism is seen in a variety
of disorders such as postencephalitic parkinsonism, arteriosclerotic parkinsonism, and post-traumatic parkinsonism
following closed head injury. Parkinson’s disease was first
described by James Parkinson in 1817. It is an idiopathic disease that mainly affects adults in middle or late life. The
reported prevalence rate in the general population is 130 in
100,000 persons; however, among those who are older than 60
years of age, the rate is considerably higher.15,16
striatum. Experiments to reduce dopamine levels in animals
have clearly shown that the classic symptoms of Parkinson’s
disease can be observed following this procedure. Thus, a low
dopamine level will result in hypokinesia whereas a high level
will lead to hyperkinesia. Symptoms similar to parkinsonism
may also be induced by drugs that cause a reduction of
dopamine in the brain, the most common of the drugs being
phenothiazine derivatives. When drugs such as these are terminated, symptoms also quickly subside. Although a definite
etiology has not been established, the most likely explanation
is that the disease results from a combination of accelerated
aging, genetic predisposition, exposure to toxins, and an
abnormality in oxidative mechanisms.15,16
Tremor, rigidity, bradykinesia, and postural instability are the
cardinal features of parkinsonism and may be present in any
combination. The tremor is most conspicuous at rest, is
enhanced by emotional stress, and tends to be less severe during voluntary activity. Rigidity (an increase in resistance to
passive movement) is responsible for the characteristically
flexed posture seen in many patients. The most disabling
symptoms are due to bradykinesia, manifested as a slowness of
voluntary movement and a reduction in automatic movements
such as the swinging of the arms while walking.
The onset of the disease is generally insidious. Mild stiffness of the muscles of the extremities and tremor of the hands
are frequently early signs. The typical hand tremor is often
called a “pill-rolling” movement, characterized by the rubbing
of the thumb against the fingers, and is particularly pronounced when the patient is otherwise at rest. The general
stiffness progresses slowly until significant disability is noted
by the patient. Walking becomes more difficult, and the
patient develops a slow shuffling gait with a stooped position.
As the ability to perform voluntary movements decreases,
patients usually experience an inability to coordinate separate
or independent movements.
Many of the signs of Parkinson’s disease are found in the
head and neck. The typical “masklike” facial appearance with
infrequent blinking and lack of expression is caused by
bradykinesis. The muscle rigidity also causes difficulty in swallowing, resulting in drooling. Speech becomes labored because
of the lack of muscle control, and mandibular tremor results
in masticatory difficulties, especially in those with removable
dental appliances. Abnormalities in oral behavior, such as purposeless chewing, grinding, and sucking movements, are also
well recognized in patients with Parkinson’s disease and make
dental treatment especially difficult.
Treatment
Etiology and Pathogenesis
MEDICAL MEASURES
In idiopathic parkinsonism, dopamine depletion due to degeneration of the dopaminergic nigrostriatal system in the brainstem leads to an imbalance of dopamine and acetylcholine,
neurotransmitters that are normally present in the corpus
Drug treatment is often not required early in the course of
parkinsonism. Patients with mild symptoms but no disability may be helped by amantadine. This drug improves all of
the clinical features of parkinsonism, but its mode of action
598
is unclear. Anticholinergics are more helpful in alleviating
tremor and rigidity than in alleviating bradykinesia, but these
drugs have many side effects. Levodopa, a dopamine precursor that can cross the blood-brain barrier, improves all the
major features of parkinsonism. This drug is used solely as
replacement therapy for the underlying dopamine deficiency;
it will neither halt nor reverse the degenerative process affecting brainstem neurons. Side effects associated with this drug
therapy may be minimized by using a combination of levodopa and carbidopa. Carbidopa prevents the destruction of
levodopa in the bloodstream, enabling lower (and therefore
less toxic) dosages to be prescribed.
Dopamine agonists act directly on dopamine receptors,
and their use in the treatment of parkinsonism is associated
with a lower incidence of the response fluctuations and dyskinesias that occur with long-term levodopa therapy. The
two most widely used agonists are bromocriptine and pergolide, which are equally effective ergot derivatives.
Pramipexole and ropinirol are two newer dopamine agonists
that are not ergot derivatives; they are more selective, have
fewer side effects, and may produce a longer-lasting response
than the older ergot derivatives.17
▼ HUNTINGTON’S DISEASE
(HUNTINGTON’S CHOREA)
GENERAL MEASURES, SURGICAL MEASURES, AND BRAIN
STIMULATION
Treatment
Physical therapy or speech therapy can help many patients.
Surgical procedures, such as thalamotomy or pallidotomy, may
be helpful for patients who become unresponsive to medical
treatment or who experience intolerable side effects from medications. Finally, high-frequency thalamic stimulation is effective in suppressing the rest tremor of Parkinson’s disease.
Because electrical stimulation of the brain has the advantages
of being reversible and of causing minimal or no damage to the
brain, its use is being explored.17
Patients with Parkinson’s disease can pose a multitude of
challenges to the dental practitioner. Patients must often be
treated in the upright position, making access to certain
areas of the oral cavity difficult for the dentist. In addition,
anxiety in a Parkinson’s disease patient can increase both the
tremor and the degree of muscle rigidity. Due to dysphagia
and an altered gag reflex, special precautions must be taken
to avoid the aspiration of water or materials used during
dental procedures. In patients who suffer with hypersialorrhea, maintaining a dry field in procedures that require such
can be especially difficult.18 Xerostomia, on the other hand,
is a common side effect of antiparkinsonism medications;
the consequent root caries and recurrent decay must be diligently treated. Patients also often have difficulty maintaining their dentition because of their physical disability. For all
of these reasons, more frequent recall may be necessary.
When dental treatment is finished, the patient should be
warned to take care when moving from a supine position to
a standing position since levodopa has a significant orthostatic hypotensive effect.
Huntington’s disease is a hereditary degenerative disease of
the central nervous system, characterized by chorea (involuntary movements) and dementia. It is inherited in an autosomal
dominant manner and occurs throughout the world and in all
ethnic groups, with a prevalence rate of about 5 per 100,000.
Clinical onset is usually between 30 and 50 years of age. The
disease is progressive and usually leads to a fatal outcome
within 15 to 20 years The gene responsible for the disease has
been located on the short arm of chromosome 4.19
The earliest manifestation of the disease consists of depression
or irritability, coupled with a slowing of cognition. There are
subtle changes in coordination and minor choreiform movements appear. The main clinical manifestation is progressively
worsening choreic movements that can be observed in the
face, tongue, and head. With time, the hyperkinesia becomes
aggravated, and movements can become violent, with difficulty in speech and in swallowing.
There is no cure for Huntington’s disease; progression cannot
be halted, and treatment is purely symptomatic. Treatment is
usually dependent on dopamine receptor blocking agents such
as haloperidol and phenothiazines, which temporarily reduce
the hyperkinesis and the behavior disturbances.19
Dysphagia and choreic movement of the face and tongue will
make dental treatment especially challenging. Sedation with
diazepam may be considered. Whenever possible, dentures
should be avoided because of the danger of fracture or the accidental swallowing of the dentures.18
▼ CEREBRAL PALSY
The term “cerebral palsy” refers to a group of disorders with
motor manifestations due to nonprogressive brain damage
occurring before or after birth. The incidence of cerebral palsy
(CP) is 2 to 6 in every 1,000 live births. There are a multiplicity of causes of CP. Anoxia and ischemia during labor have
been implicated, but congenital infections such as toxoplasmosis, rubella, Cytomegalovirus disease, herpes simplex,
syphilis, and influenza have also been associated with CP or
mental retardation.1,20
The clinical manifestations of CP can be spastic, dyskinetic,
ataxic, or a combination affecting one or all four limbs. The
spastic forms of CP are the most common, and the legs are
most commonly affected. Speaking problems are prevalent,
with dysarthria, chewing, and swallowing difficulties. Drooling
is both a functional and esthetic inconvenience. In hemiplegic
599
cases of CP, the right side is more often involved. Sometimes,
there are seizures associated with mental retardation. The dyskinetic type is characterized by athetotic purposeless movement, involving both agonist and antagonist muscles, that is
increased by voluntary activity. During either natural or
induced sleep, the movements cease. Head movements and
facial grimacing are characteristic. One should not be misled
by the appearance of the patient since most CP patients are
intellectually normal.
Treatment
With improved perinatal care, both anoxia and perinatal infections have been markedly reduced, thus leading to a reduction
in the incidence of CP. The key to success in the management
of CP is teamwork and a planned approach to the individual
child’s problem. Many children with CP have normal intelligence and should not be penalized because of dysarthria or
involuntary movements. Physiotherapy should be instituted as
early as possible in order to prevent contractures, and orthopedic surgery has been used occasionally with some degree of
success.21 If the patient suffers from seizures, appropriate drug
therapy is instituted (see “Epilepsy,” later in this chapter).
Children with CP show an increased incidence of enamel
defects, the cause of which is not clear. A much more bothersome finding is the sialorrhea and drooling experienced by
CP patients. This develops in the absence of orofacial and
neck muscle coordination. One treatment, sialodocholoplasty (the relocation of salivary gland ducts into the tonsillar fossa and the removal of the sublingual salivary glands),
has been shown to be effective.22 Less invasive management
of sialorrhea includes a systemic medication such as glycopyrolate and anticholinergic agents.23
▼ BELL’S PALSY
Bell’s palsy is recognized as a unilateral paresis of the facial
nerve. The dysfunction has been attributed to an inflammatory
reaction involving the facial nerve. A relationship has been
demonstrated between Bell’s palsy and the isolation of herpes
simplex virus 1 from nerve tissues.24–26 Bell’s palsy must be differentiated from other causes of facial nerve palsy, including
Lyme disease, herpes zoster of the geniculate ganglion (Ramsay
Hunt syndrome), and tumors such as acoustic neuromas.27
Bell’s palsy begins with slight pain around one ear, followed by
an abrupt paralysis of the muscles on that side of the face. The
eye on the affected side stays open, the corner of the mouth
drops, and there is drooling. As a result of masseter weakness,
food is retained in both the upper and lower buccal and labial
folds. The facial expression changes remarkably, and the
creases of the forehead are flattened. Due to impaired blinking, corneal ulcerations from foreign bodies can occur.
Involvement of the chorda tympani nerve leads to loss of taste
perception on the anterior two-thirds of the tongue and
reduced salivary secretion.
Treatment
The only medical treatment that may influence the outcome
is the administration of systemic corticosteroids within the
first few days after the onset of paralysis, but this therapy
should be avoided if Lyme disease is suspected. Combining
steroids with antiherpetic drugs such as acyclovir may decrease
the severity and length of paralysis.28
It is also helpful to protect the eye with lubricating drops
or ointment and a patch if eye closure is not possible. When
paralysis-induced eye opening is permanent, intrapalpebral
gold weights are inserted, thus closing the upper eyelid. Facial
plastic surgery and the creation of an anastomosis between
the facial and hypoglossal nerves can occasionally restore
partial function and improve appearance for patients with
permanent damage.
▼ GUILLAIN-BARRÉ SYNDROME
Guillain-Barré syndrome (acute idiopathic polyneuropathy)is
an acute symmetrical ascending polyneuropathy, often occurring 1 to 3 weeks (and occasionally up to 8 weeks) after an acute
infection. The Guillain-Barré syndrome often follows a nonspecific respiratory or gastrointestinal illness but has also been
described after a few specific infections (such as with
Cytomegalovirus, Epstein-Barr virus, Enterovirus, Campylobacter
jejuni, or Mycoplasma) and after immunization. There is a
worldwide incidence of 1.6 to 1.9 cases per 100,000 population
per year.29 The disorder probably has an immunologic basis, but
the precise mechanism is unclear.
The syndrome often begins with myalgia or paresthesias of the
lower limbs, followed by weakness, which often ascends to
involve abdominal, thoracic, and upper-limb muscles. In
severe cases, respiration is compromised. Involvement of the
autonomic nervous system by the disease process may induce
changes in blood pressure and pulse rate. From an oral medicine perspective, the interesting feature of this disease is the fact
that impaired swallowing or paresthesias of the mouth and
face may be early signs of the disease. The seventh cranial
nerve is frequently involved, and bilateral facial weakness is
common. Involvement of other cranial nerves may result in
ptosis or facial myokymia. Dysarthria, dysphagia and diplopia
may develop in severe cases.
Treatment and Prognosis
The paralysis in Guillain-Barré syndrome may progress for
about 10 days and may then remain relatively unchanged for
about 2 weeks. The recovery phase is much slower and may
take from 6 months to 2 years for completion. Permanent signs
of neurologic damage can persist in some patients.
Treatment with prednisone is ineffective and may actually
affect the outcome adversely by prolonging recovery time.
600
Plasmapheresis is of value; however it is best performed within
the first few days of illness and is best reserved for clinically
severe or rapidly progressive cases.1
▼ MYASTHENIA GRAVIS
Myasthenia gravis (MG) is a disease characterized by progressive muscular weakness on exertion, secondary to a disorder at the neuromuscular junction. Acetylcholine normally transmits the impulse from nerve to muscle at the
neuromuscular junction, and cholinesterase hydrolyzes
acetylcholine. In patients with MG, autoantibodies that
combine with and may destroy the acetylcholine receptor
sites at the neuromuscular junction are present, preventing
the transmission of nerve impulses to the muscle. The origin of the autoantibodies is unknown, but other findings
linking MG to autoimmunity include the incidence of thymoma in MG patients, the improvement of symptoms after
thymectomy, and the association of MG with other diseases
involving abnormal immune phenomena, such as pemphigus, pemphigoid, systemic lupus erythematosus, and
rheumatoid arthritis. The disease occurs more frequently in
women than in men, particularly during the third and
fourth decades of life.30
The initial signs of this disease commonly occur in areas innervated by the cranial nerves (frequently, the eye muscles).
Patients present with ptosis, diplopia, difficulty in chewing or
swallowing, respiratory difficulties, limb weakness, or some
combination of these problems. In some patients, the disease
remains confined to the eye muscles, but in most cases, it progresses to other cranial nerves as well as to the shoulders and
limbs. MG follows an unpredictable course, and exacerbations
and remissions occur frequently. In severe advanced cases, respiratory difficulty arises.
Diagnosis is made initially on the basis of clinical presentation. The inability of a patient to continually blink the
eyes voluntarily is highly suggestive of MG. The clinical diagnosis can be confirmed by the dramatic improvement of
symptoms with the administration of a short-acting anticholinesterase; it will antagonize the effect of cholinesterase
on acetylcholine, allowing increased levels of this chemical at
the neuromuscular junction. Specific tests for detecting the
antiacetylcholine receptor antibody are now available for
confirmation of diagnosis.
Treatment
Anticholinesterase drugs such as neostigmine and pyridostigmine bromide provide symptomatic benefit without
influencing the course of the disease.30 In patients with more
severe disease, remission may be achieved by thymectomy. In
other cases, long-term cortico-steroids and immunosuppressive drugs are necessary. Plasmapheresis has been of
temporary value in patients with severe exacerbations
of MG.
Oral and facial signs are an important component of the clinical picture of MG. The facial muscles are commonly involved,
giving the patient an immobile and expressionless appearance. This has led to the incorrect diagnosis of psychiatric disease in MG patients. Tongue edema may also be present in
MG, making eating difficult for patients.31 Patients whose
muscles of mastication are weakened can also experience consequent difficulty in chewing; these patients will be unable to
finish chewing a bolus of food because of the easy fatigability
of the muscles. It is essential to be aware that this may be an
early sign of disease. The patient’s masticatory muscles may
become so tired that the mouth remains open after eating. An
important indication of MG is a patient who must hold his
jaws closed with his hand.
When treating known MG patients, the dentist must be
aware that a respiratory crisis may develop from the disease
itself or from overmedication. If a patient is at risk for developing a respiratory crisis, dental treatment should be performed in a hospital where endotracheal intubation can be
performed. The airway must be kept clear because aspiration
may occur in patients whose swallowing muscles are
involved. Adequate suction and the use of a rubber dam are
aids in these cases.
The dentist should avoid prescribing drugs that may affect
the neuromuscular junction, such as narcotics, tranquilizers,
and barbiturates. Certain antibiotics, including tetracycline,
streptomycin, sulfonamides, and clindamycin, may reduce
neuromuscular activity and should be avoided.
▼ MUSCULAR DYSTROPHY
Muscular dystrophy (MD) is a genetic disease characterized by
muscle atrophy that causes severe progressive weakness. The
primary biochemical defect has not been identified, but evidence is accumulating to implicate an enzymatic dysfunction
at the muscle surface membrane.
The various forms of MD are genetically determined
myopathies characterized by progressive muscular weakness
and the degeneration of muscle fibers. The muscular dystrophies are classified according to mode of inheritance, age at
onset, and clinical features.
DUCHENNE’S MUSCULAR DYSTROPHY
Duchenne’s muscular dystrophy is the most common form of
MD and is seen almost exclusively in young males. This type
of MD is a result of a mutation of the dystrophin gene located
on the short arm of the X chromosome.32 Clinical manifestations begin during the first 3 years of life. Affected children
appear normal at birth and may be extremely placid. Early
signs are difficulty in walking, frequent falling, and the inability to run. Symptoms progress as muscles continue to atrophy.
Initially, the atrophy is marked although muscles may appear
even larger than normal, primarily because of the fat deposi-
601
tion in the muscles. Pseudohypertrophy of muscles frequently
occurs at some stage. Intellectual retardation is common, and
there may be skeletal deformities, muscle contractures, and
cardiac involvement. Serum levels of the enzyme creatine
phosphokinase are elevated in affected males as well as in
female carriers.
At the end of the first decade of life, the child will be unable
to walk and will be bedridden. Respiratory muscles will begin
to be affected, and most patients die in the late teenage years
or early twenties. A better understanding of pulmonary problems and improved treatment of respiratory infections have
increased the life span of these patients. The muscles of the
pelvis and femoral region are most severely affected by the
Duchenne form of MD, but the muscles of the face, head, and
neck are not involved.
BECKER’S MUSCULAR DYSTROPHY
Becker’s MD is a milder expression of the disease, caused by
mutation of the dystrophin gene. There is a wide range of presenting symptoms that vary in severity from a slightly milder
form of the disease resembling Duchenne’s MD to an asymptomatic elevation of creatine kinase. The age of onset is
between 5 and 25 years, with a mean age of 11 years.32 The progression of Becker’s MD is slow, and patients may have a normal life span.
FACIOSCAPULOHUMERAL DYSTROPHY
Facioscapulohumeral dystrophy is inherited as an autosomal
dominant trait and affects both males and females. Symptoms
do not usually begin until the second decade of life. It is not as
universally devastating as the Duchenne form of MD, and
some patients may live a normal life span with minimal physical disability. The muscles of the face and pectoral girdle are
most severely involved, and these patients characteristically
exhibit weakness of the arms, winging of the scapulae, and
weakness of the muscles of the eyes and mouth.
LIMB-GIRDLE DYSTROPHY
Limb-girdle MD is inherited, usually as an autosomal recessive
trait; however, it may also be sporadically or dominantly inherited. It affects both sexes and has its onset in the second and
third decades of life. The weakness starts in either the shoulders or the pelvis but will eventually spread to both. This is
characteristically a slowly progressing form of MD. Facial muscles are not involved.
MYOTONIC DYSTROPHY
Myotonic dystrophy is a multisystem disorder inherited as an
autosomal dominant trait through a locus on chromosome
19.1 The signs and symptoms may appear at any time from
birth to the age of 40 years, and the disease is characterized by
progressive muscular weakness, myotonia, cataracts, cardiac
abnormalities, hypogonadism, and frontal balding. The most
severe involvement occurs in the muscles of the head and neck
and in the distal extremities. Myotonia is the persistence of the
contraction of muscles; in this form of MD, the patient is
unable to relax the muscles after contraction. This symptom
can be best observed in the forearm, thumb, and tongue.
Wasting of muscles and subsequent weakness are as prominent
as in other forms of MD. Involvement of the facial muscles and
hands is especially striking. Cardiac abnormalities may include
a prolapsed mitral valve and atrial flutter; patients with more
advanced cases have severe cardiac fibrosis.33
Treatment
All forms of MD are incurable, and no satisfactory method of
retarding the muscle atrophy exists. Corticosteroids have been
shown to decrease the rate of muscle loss, but only in the short
term. A physical therapy program will help to delay the development of joint contractures, and orthopedic procedures may
help to counteract deformities. The ultimate outcome in severe
forms of the disease is grave.34
Oral and facial signs are prominent in the facioscapulohumeral
and myotonic forms of MD. Patients with the myotonic-type
disease develop severe atrophy of the sternomastoid muscles,
with a resultant difficulty in the ability to turn the head. The
muscles of facial expression and mastication are also commonly affected, such that the patient has difficulty in chewing
or in pursing the lips. Weakness of the facial muscles and
enlargement of the tongue due to fatty deposits has been occasionally observed. Patients with the oculopharyngeal form of
the disease have significant difficulty in swallowing.
Occlusal abnormalities have also been reported in patients
with MD. This is thought to result from the lack of the proper
muscle tension necessary to keep the teeth properly aligned in
the dental arch. If the tongue is enlarged and the facial muscles are weak, the teeth will be pushed out. Other abnormalities include macroglossia, anterior open bite, and (occasionally) temporomandibular joint dysfunction.
OCULOPHARYNGEAL MUSCULAR DYSTROPHY
▼ EPILEPSY
A rare form of MD, oculopharyngeal MD is inherited as an
autosomal dominant trait and is characterized by the late onset
of chronically progressive ptosis and dsyphagia. Symptoms
may begin at any age and consist of progressive weakness of
levator palpebrae and chronic contraction of the frontalis
muscle. The patient will maintain a chin-up head position and
will have difficulty in swallowing solid food initially and liquids later. A late weakness of limb-girdle muscles may occur.
Epilepsy is a condition characterized by abnormal, recurrent,
and excessive neuronal discharges precipitated by many different disturbances within the central nervous system. These
aberrant discharges may cause episodes of sensory and motor
abnormalities as well as loss of consciousness. Each episode of
aberrant neurologic activity is referred to as a seizure. Epilepsy
is common, affecting approximately 0.5% of the population in
the United States.35 Although the disease may occur at any
602
stage of life, the age of the patient at the onset of seizures is
closely associated with the various causes of epilepsy. Infants
are much more likely to suffer from epilepsy after complications at birth, such as anoxia, intracranial injury, metabolic disorders, and congenital malformations. Predominant causes in
children and adolescents include trauma and acute or febrile
infections whereas young adults who have engaged in alcohol
or drug abuse commonly suffer from generalized seizures after
periods of severe abuse. Epilepsy in older adults may occur as
a complication of any of the previously mentioned causes but
is more often associated with cerebrovascular diseases such as
stroke and tumor.
Classification of Seizures
Seizures can be categorized in various ways, but the descriptive classification proposed by the International League Against
Epilepsy is clinically the most useful. Seizures are divided into
those that are generalized and those that affect only part of the
brain (partial seizures)36 (Table 23-1). Simple partial seizures
originate from one localized area of the brain and do not feature loss of consciousness. In contrast, complex partial
seizures, often referred to as temporal lobe or psychomotor
seizures, are associated with an impairment of consciousness.
The majority of generalized seizures are called either absence
(petit mal) seizures or tonic-clonic seizures (grand mal). The
remaining generalized seizure types described in the classification (ie, myoclonic or infantile seizures and clonic, tonic, and
atonic seizures) are usually found in childhood and carry a
poorer prognosis for normal childhood development. “Status
epilepticus” refers to a period of recurrent seizure attacks without recovery between each attack. All forms of seizure may
progress to a period of status epilepticus.
Nonspecific changes such as headache, mood alterations,
lethargy, and myoclonic jerking alert some patients to an
impending seizure hours before it occurs. These prodromal
symptoms are distinct from the aura that may precede a gener-
TABLE 23-1 International Classification of Epileptic Seizures
Partial (focal) seizures
Simple partial seizures
Complex partial seizures
Partial seizures leading to secondarily generalized seizures
Generalized Seizures
Absence seizures
Typical
Atypical
Myoclonic seizures
Clonic seizures
Tonic seizures
Tonic-clonic seizures
Atonic seizures (astatic seizures)
Adapted from Kelley WN, DeVita VT Jr, Dupont HL, Harris Ed Jr. Internal medicine
for dentistry. 2nd ed. Philadelphia: J.B. Lippincott; 1992.
alized seizure by a few seconds or minutes and that is itself a part
of the attack, arising locally from a restricted region of the brain.
The most common type of seizure is the tonic-clonic or
grand mal seizure; 90% of epileptics experience it alone or in
combination with another type of seizure. A grand mal seizure
characteristically begins with an aura. The aura may be experienced as epigastric discomfort, as an emotion, or as an hallucination of hearing, vision, or smell. The aura is followed seconds to minutes later by unconsciousness, a cry, and tonic
muscle spasms; this rigid phase lasts about 30 seconds. Because
of the spasm of the respiratory muscles, the patient does not
breathe and becomes cyanotic during this period. The tonic
phase is followed by a clonic phase composed of convulsive jerky
movements, incontinence, and tongue biting (Figure 23-1). The
patient may injure him- or herself seriously if he or she is near
hard or sharp objects.A postictal state characterized by headache,
confusion, lethargy, occasional temporary neurologic deficit, and
deep sleep usually follows a grand mal seizure.
The number, severity, and duration of grand mal seizures
vary considerably from one patient to another. Status epilepticus,
a severe form of the disorder, occurs when a series of seizures follow each other before the patient is able to regain consciousness.
Absence or petit mal seizure is the second most common
type of seizure, and it occurs without an aura and with few or
no clonic or tonic movements. Absence seizures present almost
exclusively in children and frequently disappear during the
second decade of life. A single seizure lasts just seconds. The
patient loses consciousness and appears to stare into space. He
or she continues normal activity immediately after the seizure
is over. Petit mal seizures may occur several times each day, and
severe cases may interfere with school and social activities.
Around puberty, approximately 50% of persons who experience petit mal seizures will develop tonic-clonic seizures.
Treatment of Seizures
For patients with recurring seizures, drug treatment is prescribed with the goal of preventing further attacks and is
usually continued until there have been no seizures for at
least 3 years.35
The drug with which treatment is best initiated depends on
the type of seizures to be treated. The dose of the selected drug
is gradually increased until seizures are controlled or until side
effects prevent further increase. If seizures continue despite
treatment at the maximal tolerated dose, a second drug is
added. The second drug’s dose is increased, depending on the
patient’s tolerance, and the first drug is then gradually withdrawn. In the treatment of partial and secondarily generalized
tonic-clonic seizures, the success rate is higher with carbamazepine, phenytoin, or valproic acid than with phenobarbital or primidone. Gabapentin, topiramate, and lamotrigine
are newer antiepileptic drugs that are effective adjunctive therapy for partial or secondarily generalized seizures. In most
patients with seizures of a single type, satisfactory control can
be achieved with a single anticonvulsant drug.37,38
The choice of medication is usually related to individual tolerance and efficacy, but it should be remembered that all of
603
A
B
FIGURE 23-1 A, Bilateral human bites of the upper lip, received during an epileptic seizure. B, Traumatic injury (bite) to tongue occurred during an
epileptic seizure.
these drugs produce significant but different side effects, including blood dyscrasias, anemia, and alteration of hepatic function.
Patients with epilepsy may be treated in the private dental setting. A thorough medical history should indicate what type of
seizures the patient has, how well the seizures are controlled,
the frequency and duration of seizures, the potential triggers
for seizures, and what to expect if the patient has a seizure.
Treatment planning may be altered, however, depending on the
status of the seizure disorder. As a general rule, it is better to
place a fixed prosthesis rather than a removable appliance
because of the potential for removable appliances to become
dislodged during a seizure.39
Patients who are taking anticonvulsant drugs are subject to
gingival overgrowth. This overgrowth is most often associated
with patients who are taking phenytoin (Figure 23-2). About
half of the patients placed on phenytoin will show evidence of
gingival enlargement, usually within 2 to 18 months after starting the medication. The etiology is still unknown, but there
appears to be an increase in the number of fibroblasts in the
A
connective tissues.40 Gingival overgrowth may occur at any age
but seems to affect younger patients to a greater degree than
adults. Men and women are equally affected. There does not
appear to be a correlation between dosage and the incidence
of gingival overgrowth. There is strong clinical evidence of a
correlation between poor oral hygiene and the amount of tissue enlargement.
Clinically, phenytoin gingival overgrowth starts in the interdental papillae and occurs only where teeth are present. The
papillae enlarge buccally and lingually. The enlarged areas are
firm, pink, and covered with normal mucosa. The severity of the
hyperplasia varies. In some patients, the enlarged gingivae may
involve just one or two papillae; in other cases, the crowns of the
teeth are completely covered with gingival tissue. The best treatment of phenytoin gingival overgrowth begins with prevention.
Little doubt remains that careful oral hygiene can prevent or at
least minimize the gingival enlargement. Soon after being placed
on anticonvulsant therapy, each patient should be referred to a
dentist for oral hygiene instruction and gingival curettage.
Patients who have not been properly managed and who develop
gross gingival enlargement will require gingivectomy. Curettage
B
FIGURE 23-2 A, Phenytoin gingival overgrowth in a 17-year-old girl. The enlarged tissues are light pink and fibrous, and they show no evidence
of edema, inflammation, or ulceration. B, Patient with phenytoin gingival overgrowth following electrocautery of enlarged gingival tissues. The excess
maxillary gingival tissue had been removed 10 days previously. The excess mandibular gingival tissue had just been removed. Fractures of the mesioincisal
angles of the maxillary first incisors occurred during a seizure.
604
and careful attention to oral hygiene must follow the surgery, or
the hyperplastic tissue will return.
It is known that side effects other than gingival overgrowth
also occur in patients taking phenytoin. This includes megaloblastic anemia, hirsutism, and lymphadenopathy. Changes in
connective tissue and bone (including osteomalacia, thickening of the heel pad and of the calvarium, and coarse facies)
have also been reported.40 Routine dental treatment for
patients with well-controlled epilepsy may be performed with
no change from normal treatment. There is no reason to
increase the dose of anticonvulsant therapy prior to dental
treatment, and routine use of sedation is not indicated.
▼ REFERENCES
1. Gilroy J. Basic neurology. 3rd ed. New York: McGraw-Hill;
2000.
2. Adams HP Jr, Brott TG, Furlan AJ, et al. Guidelines for thrombolytic therapy for acute stroke: a supplement to the guidelines
for the management of patients with acute ischemic stroke.
Stroke 1996; 27:1711–8.
3. Wolf PA, Clagett GP, Easton JD, et al. Preventing ischemic
stroke in patients with prior stroke and TIA: a statement for
healthcare professionals from the stroke council of the
American Heart Association. Stroke 1999;30:1991–4.
4. Victor M, Ropper AH. Adams and Victor’s principles of neurology. 7th ed. New York: McGraw-Hill; 2001.
5. Feinberg WM, Albers GW, Barnett HJ, et al. Guidelines for the
management of TIAs. From the Ad Hoc Committee on
Guidelines for the Management of Transient Ischemic Attacks
of the Stroke Council of the American Heart Association.
Circulation 1994;89:2950–65.
6. Ostuni E. Stroke and the dental patient. J Am Dent Assoc
1994;125:721–7.
7. Kurtzke JF, Hellested K. Multiple sclerosis in the Faroe Islands:
clinical and epidemiological features. Ann Neurol 1979;5:6.
8. Sadovnick AD, Ebers GC. Genetics in multiple sclerosis. Neurol
Clin 1995;13:99–118.
9. Mumford CJ, Wood NW, Kellar-Wood H, et al. The British
Isles survey of multiple sclerosis in twins. Neurology
1994;44:11–5.
10. Rudick RA, Cohen JA, Weinstock-Gutman B, et al.
Management of multiple sclerosis. N Engl J Med 1997;
337:1604–11.
11. Chemaly D, Lefrancois A, Perusse R. Oral and maxillofacial
manifestations of multiple sclerosis. J Can Dent Assoc 2000;
66:600–5.
12. Gale D, Prime S, Campbell MJ. Trigeminal neuralgia and multiple sclerosis, a complex diagnosis. Oral Surg Oral Med Oral
Pathol Oral Radiol Endod 1995;79:398–401.
13. Houde SC, Mangolds V. Amyotrophic lateral sclerosis: a team
approach to primary care. Clin Excell Nurse Prac 1999;
3(6):337–45.
14. Asher RS, Alfred T. Dental management of long-term amyotrophic lateral sclerosis: case report. Spec Care Dentist
1993;13(6):241–4.
15. Lang AE, Lozano AM. Parkinson’s disease. Part 1. N Engl J
Med 1998;339:1044–53.
16. Lang AE, Lozano AM. Parkinson’s disease Part 2. N Engl J Med
1998;339:1130–43.
17. Olanow CW, Koller WC. An algorithm for the management of
Parkinson’s disease: treatment guidelines. Neurology 1998;50(3
Suppl 3):S1–57.
18. Kieser J, Jones G, Borlase G. Dental treatment of patients with
neurodegenerative disease. N Z Dent J 1999;95(422):130-4.
19. Quinn N, Schrag A. Huntington’s disease and other choreas. J
Neurol 1998;245(11):709-16.
20. Bass N. Cerebral palsy and neurodegenerative disease. Curr
Opin Pediatr 1999;11(6):504–7.
21. Dabney KW, Lipton GE, Miller F. Cerebral palsy. Curr Opin
Pediatr 1997;9(1):81–8.
22. Becmeur F, Horta-Geraud P, Brunot B, et al. Diversion of salivary flow to treat drooling in patients with cerebral palsy. J
Pediatr Surg 1996;31(12):1629–33.
23. Bachrach SJ, Walter RS, Trzcinski K. Use of glycopyrrolate and
other anticholinergic medications for sialorrhea in children
with cerebral palsy. Clin Pediatr 1998;37(8):485–90.
24. Murakami S, Mizobuchi M, Nakashiro Y, et al. Bell’s palsy and
herpes virus: identification of viral DNA in endoneurial fluid
and muscle. Ann Intern Med 1996;124:27–30.
25. Sanchez Rodriguez A. Bell’s palsy in association with herpes
simplex virus infection. Arch Intern Med 1998;158(14):1577–8.
26. Nasatzky E, Katz J. Bell’s palsy associated with herpes simplex
gingivostomatitis: a case report. Oral Surg Oral Med Oral
Pathol 1998;86(3):292–6.
27. Billue JS. Bell’s palsy: an update on idiopathic facial paralysis.
Nurse Pract 1997;22(8):88,97–100,102–5.
28. Adour KK. Bell’s palsy treatment with acyclovir and prednisone compared with prednisone alone: a double-blind, randomized, controlled trial. Ann Otol Rhinol Laryngol 1996;
105:371–8.
29. Van der Meche FG, Aan Doorn PA, Meulstee J, et al. Diagnostic
and classification criteria for the Guillain-Barre syndrome. Eur
Neurol 2001;45(3):133–9.
30. Keesey J. Myasthenia gravis. Arch Neurol 1998;55(5):745–6.
31. Davison SP. Swollen tongue: a presentation of myasthenia
gravis. Otolaryngol Head Neck Surg 1997;116(2):244–6.
32. Ptacek L. The familial periodic paralyses and nondystrophic
myotonias. Am J Med 1998;104:58–70.
33. Arahata K. Muscular dystrophy. Neuropathology 2000 Sep; 20
Suppl:S34-41.
34. Urtizberea JA. Therapies in muscular dystrophy: current concepts and future prospects. Eur Neurol 2000;43(3):127–32.
35. Browne TR, Holmes GL. Epilepsy. N Engl J Med 2001;
344(15):1145–51.
36. Proposal for revised clinical classification of epileptic seizures.
From the Commission on Class and Terminology of the
International League Against Epilepsy. Epilepsia 1981; 22:489–501.
37. Bradie MJ, Dichter MA. Antiepileptic drugs. N Engl J Med
1996;334:168–75.
38. Mattson RH. Medical management of epilepsy in adults.
Neurology 1998;51 Suppl 4:515–20.
39. Sanders BJ, Weddell JA, Dodge NN. Managing patients who
have seizure disorders: dental and medical issues. J Am Dent
Assoc 1995;126:1641–7.
40. Perlik F, Kolinova M, Zvarova J, et al. Phenytoin as a risk factor
in gingival hyperplasia. Ther Drug Monit 1995;17(5):445–8.

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