Dentistry
Introduction Dental
disease is potentially life threatening as a defect in a tooth from a dental cavity
or from periodontal disease or from neglected decay (caries) can lead to tooth
infections that worm their way into the blood stream and can lead to dental abscesses
and to sepsis. In people with heart valve problems this can lead to bacterial
endocarditis, which has the potential to become a life threatening infectious
condition. When people are in their thirties or forties, it is not uncommon to
develop the first root canal problem. When a cavity gets deep enough to affect
the blood supply of the nerve that supplies the tooth with sensory fibers, the
nerve dies off and the person may not feel that there is anything wrong with the
tooth unless it is checked out by a dentist. Eventually the deeper nerve fibers
or the neighboring nerves of the adjacent teeth get irritated and the patient
feels a deep gnawing pain. This is when the patient is usually seen by the dentist
and a root canal followed by a crown is often required. Before a number of common
dental conditions are described in more detail, here is a brief description of
the anatomy of a tooth.
A tooth has a crown and a root. The crown is coated with a very hard enamel layer
and is what we see when a person smiles. The root is buried in the mandibular
or maxillary bone, which gives the tooth a very solid footing. The pulp chamber
is surrounded by a hard, but porous dentin layer, which is coated with enamel
on top and with the bone-like cementum over the root. Gingiva is part of the supportive
tissue of the teeth and together with the periodontal ligaments and connective
tissue attaches the teeth firmly within the alveolar bone where the teeth are
anchored. The pulp contains the nerve endings and blood and lymphatic vessels
that enter the pulp cavity through the root canal. The other important ingredient
in the oral cavity is the constant secretion from the salivary glands that bathe
the teeth in saliva and keep the bacterial flora diluted. The tongue with its
very sensitive nerve endings helps to spot remaining food particles on top and
between the teeth, which helps to clean and protect the teeth from decay.
Tooth Decay Tooth decay occurs mostly on top of the
enamel coating, which can occur in the crown of any tooth. In elderly persons
where there is less saliva for protection and the root is more exposed because
of gingiva retraction, severe tooth decay at the root level can cause the loss
of several teeth. As early tooth decay, called caries, is painless in the first
few months, the only rational approach is to have regular check-ups with the dentist
every 6 months. The dentist will use a sharp instrument to probe for soft spots
in the enamel. These usually start around micro fissures in the tooth that can
extend down to the dentin level. Other tests such as X-rays will also show the
extent of the tooth decay. When dental cleaning has not been done every 6 months,
a thin coat of plaque from old decayed food and bacteria is on top of the enamel.
The bacteria produce acids that burn holes into the enamel. Mutans streptococci
with varies subspecies specialize in growing in plaque. Cola drinks with phosphoric
acid, sugar and other sweets that feed the mutans bacteria all contribute to the
tooth decay process.
Signs and symptoms Sometimes there is a discoloration
of the enamel, but as long as the tooth decay involves only the enamel layer,
there is no pain. Pain starts when the cavity invades the dentin level of the
tooth. Sensitivity with cold and hot foods and beverages indicates that there
is a defect in the enamel that reaches down to the dentin level. This is a late
sign telling the patient to quickly see a dentist. If this does not happen, chewing
becomes painful as well and the patient may awake in the middle of the night with
a tooth ache. As the dentin is porous, bacteria find it easy to invade into the
pulp cavity leading to a pulpitis and root canal infection.
Treatment The dentist needs to assess the depth of the
tooth decay and remove anything that is decayed. This is done by drilling. More
severe cavities need to be X-rayed to determine the depth of the decay. If the
pulp has been affected, a root canal treatment with a crown is the treatment of
choice. If the decay involves only the superficial enamel, a filling will preserve
the tooth with its root intact. There has been a heated debated about the use
of silver amalgam, which contains silver, mercury, tin, copper, zinc and other
traces. Over the years this has been providing fillings that lasted on average
of 14 to 15 years. Newer materials have been developed and are now very popular
because of the fear of systemic mercury blood poisoning. For those of you who
may be skeptical about the effects
of mercury from fillings, here is a You tube link to convince you otherwise.
Mercury poisoning has been first detected in children with autism, but lately
more and more evidence has accumulated regarding Parkinson's disease and Alzheimer's
disease as neurological disorders that can be directly linked to mercury fillings
(the more fillings, the more severe the disease). Books like "Breakthrough"
(Ref.1) by Suzanne Somers have reviewed newer insights of antiaging medicine.
This points out the importance of detoxifying the body from heavy metals like
mercury, lead and cadmium. This can be done using a non-drug method stimulating
the body's own glutathione and carnosine detoxification system (Y-Age
patches from Lifewave). This link tells you more about this detoxification
method (click "products"). These patches are FDA approved and based
on nanotechnology, a newer technology, which is involved in the manufacturing
of these patches. Infrared (heat) waves from body heat are utilized to energize
an acupuncture point, which in turn stimulates the production of either glutathione
or of carnosine in the body. These two patches are applied on alternating days
(for more info see Lifewave link). Composite resins that have a more pleasing
appearance and have been used in the past for repairs of the visible front teeth,
are now used more and more for molar teeth, even though they last only half as
long as the traditional silver/mercury amalgam fillings. Newer porcelain or ceramic
inlays are now being used as well, but it is not known yet how long these will
last. The "gold standard" is the use of gold inlays and gold crowns
as they last 30 to 40 years. However, this needs to be combined with an aggressive
prevention program consisting of dental cleaning and fluoride treatment every
6 months and daily brushing with a soft tooth brush after every meal and flossing
once every 24 hours. Flossing prevents gingivitis and periodontal disease. It
takes only 24 hours for soft tartar to form (=plaque) and within a few days this
gets calcified and becomes hard plaque that will not be removed with regular brushing.
Personally, I would recommend that you ask your dentist to replace all silver
amalgam fillings (they contain mercury) with these latter materials.
Gingivitis The middle third of the tooth is imbedded
in gingiva. Without flossing the gingiva forms pockets that are colonized with
the acid forming bacteria (mutans streptococci mentioned under tooth decay above).
This leads to a pH of less than 5.5 and subsequent decalcification of enamel and
cementum where the gingiva has retreated and the neck of the teeth has been exposed.
The next step is tooth decay and cavity formation. Chronically inflamed gingiva
is called gingivitis, a painful gum disease, which can cause bleeding after minor
mechanical impact such as chewing food. A lack of dental hygiene (not brushing,
not flossing) leads to gingival pockets harboring even more bacteria and accelerating
tooth decay. Gingivitis
occurs commonly also during puberty, during menstruation, pregnancy and if a patient
is on the birth control pill. Some medical conditions such as diabetes and AIDS
are known to be associated with a higher incidence of gingivitis as are severe
vitamin C and niacin deficiency. Patients with Crohn’s disease also are more
susceptible to develop gingivitis. A severe form of acute necrotizing ulcerative
gingivitis is also called a “trench mouth” or “Vincent’s infection or
angina”. This can occur in smokers or debilitated persons under extreme stress.
Other contributing factors are poor oral hygiene, sleep deprivation and nutritional
deficiency.
Treatment of gingivitis Gingivitis can be almost completely
prevented by regular dental hygiene consisting of regular tooth brushing and flossing.
By removing plaque every 6 month (in high risk conditions mentioned above more
often, perhaps up to 4 times per year) the mouth flora changes into a more caries
resistant flora with much less likelihood of gingivitis developing. The dentist
may decide to intervene with minor surgery, if the pockets have an excessive depth,
severe infection or abscess formation. More severe cases may need antibiotics
and debridement by a dentist or oral surgeon.
Periodontitis When gingivitis is worsening, it can
affect the periodontal support tissues, the gingiva, the alveolar bone, the periodontal
ligament and the cementum layer. When these structures are inflamed, periodontitis
has begun. Without acute intervention with the help of a dentist this leads to
chronic periodontitis. Often this develops in patients with chronic diseases such
as Crohn’s disease, diabetes, immune deficiencies, connective tissue weaknesses
like Ehlers-Danlos syndrome and others. HIV associated periodontitis is particularly
aggressive and requires close attention and treatment. This is similar to acute
necrotizing ulcerative gingivitis, but with this progressive periodontitis 9 to
12 mm of attachment of gingiva to the teeth gets lost in only 6 months. This allows
mouth bacteria and pathological bacteria to cause accelerated decay
of the roots.
Signs and symptoms There is surprisingly little in terms
of symptoms. However, with meals the periodontal pockets cause pain and trigger
a check-up with the dentist who readily diagnosis periodontal disease as there
are pockets of more than 4 mm depth. Dental X-rays show loss of alveolar bone.
Treatment of periodontitis Periodontal disease is treated
by close follow-up with the dentist. Initially the patient may have to be seen
every two weeks with increasing intervals between visits when the condition improves.
In the beginning the dentist will do scaling and root planning. This consists
of removing diseased dentin. The root needs to be smoothened to make it difficult
for pathological acid producing bacteria to grow. Plaque and calcium deposits
are removed; any defects have to be restored. The patient supplements this periodontal
disease treatment program by doing frequent tooth brushings at home with a soft
tooth brush and by flossing. When the pockets remain less than 4 mm, the only
maintenance treatments required are regular cleanings by the dentist. If deeper
pockets persist, a more vigorous treatment program is utilized involving antibiotics
and periodontal surgery. Occasionally pocket reduction surgery and tooth splinting
for loose teeth are required.
Pulpitis and Root Canal Infection Pulpitis is an inflammation
of the dental pulp that develops when tooth decay (caries) is left untreated.
It can also follow untreated trauma to a tooth or after extensive restorative
work has been done for tooth decay. When a cavity reaches deep into the dentin
layer of the tooth or when trauma affects the lymphatic flow or the blood vessels
within the root and the pulp of the tooth, pulpitis develops as a reversible condition.
When the cavity is repaired by the dentist, the inflammation of the pulp often
subsides and the tooth may survive unharmed. If the swelling inside the rigid
dentin layer is not subsiding, the circulation through the narrow root canal comes
to a stop and the pulp inside the tooth dies off. This is known as irreversible
pulpitis and is very susceptible to infection. Dental x-rays help the dentist
to assess the extent of the tooth
decay and whether or not the alveolar bone has been eroded.
Signs and symptoms With reversible pulpitis there is
hypersensitivity to cold food products or to sweets. When the stimulus is removed
by rinsing out the mouth cavity, the pain is gone within 1 to 2 seconds. With
irreversible pulpitis the condition is much more difficult to pinpoint as the
symptoms are more subtle and confusing. First, there is often a spontaneous onset
of pain, but the tooth ache is less well localized. If there is aggravation by
cold or hot food, this lingers on for much longer, even when the stimulus is removed.
The patient has sometimes difficulties to localize the root canal pain as it is
more diffuse in nature and the tooth pain may even switch between the upper and
lower teeth, which are either supplied by the maxillary nerve or the mandibular
nerve. Interestingly, there is never confusion between right and left. When the
nerve is dead, the pain can disappear for a few days, but new pain symptoms arise
as complications of super infection set in. As the infection spreads through the
apical foramen from inside the tooth to the apex of the tooth, the whole tooth
gets lifted from the tooth abscess, which is sensed by the patient as the tooth
being “too high” and being painful with every bite. This is an emergency and
requires intervention by the dentist. At this late stage the tooth may need to
be extracted. If this condition is left untreated this can lead to cellulitis,
osteomyelitis, parapharyngeal abscess, mediastinitis, pericarditis and even to
a brain abscess or to sepsis.
Treatment As already discussed, treatment for reversible
pulpitis consists of a repair of the cavity and tooth restoration. With irreversible
pulpitis root
canal treatment (endodontic treatment) is required. This involves the
reaming out of the dead pulp including the root canal nerves. Next the root canal
is filled with a rubber like substance, called gutta percha, and the tooth is
topped with a crown (out of gold or porcelain). When all is done, the patient
should no longer have pain and x-rays a few months later would show that all of
the radiolucency of the apical bone has normalized.
Tooth Fracture The severity of a fractured tooth
can vary from a crack in the crown to a crack lengthwise in the entire tooth (split
tooth) to a broken off tooth. A bad habit of grinding the teeth (bruxism) predisposes
the person to tooth fractures. If the patient is able to present with the avulsed
tooth within an hour of the accident, the dentist may be able to re-implant the
tooth. However, the tooth should be kept moist in milk (or 0.9% saline solution)
without manipulations of the root where the vital periodontal ligament remnants
will help increase the chance of tooth survival when re-implanted. Antibiotics
are usually also given for a period of time.
Abscessed Tooth and Tooth Infection Even though
a tooth abscess often comes on suddenly and leads to a tooth pain that is unbearable,
there is usually a long history of neglect of dental hygiene and a lack of regular
check-ups with the dentist, which eventually leads to this dental emergency. This
can come from a crack in the crown of a tooth that allows infection to go into
the pulp and the root of the tooth. Any defect in the dentin encasing of the pulp
and the root canal will allow mouth bacteria to cause an infection of the pulp
and the apex of the tooth (located at the bottom of the tooth).
Symptoms This leads to swelling of the gum tissue around
the abscessed tooth. There may be a foul odor, throbbing pain and pain with chewing.
Hot or cold food items will make the pain worse and the pain will linger on even
later. There can also be a fever and the regional lymph glands may be swollen.
The dentist confirms the presence of an abscessed tooth by inspecting, palpating
and tapping. An x-ray confirms the abscess at the bottom (apex) of the tooth.
Treatment Antibiotics
and pain medication is given initially. If the abscess is too far gone, the dentist
will have to do a tooth extraction. However, if the tooth can be preserved, the
cause of the infection has to be identified and treated. This could have come
from a defective filling with further tooth decay or from a crack in the crown
of the tooth from grinding the teeth. At any rate, the infected pulp and nerve
in the root canal has to be removed as described under “pulpitis and root canal
infection”. After the systemic infection has been cleared, the dentist likely
will suggest attaching a crown of gold or porcelain to add stability to the top
of the tooth. More
info on abscessed tooth Bruxism Clenching
or grinding of teeth is medically called “bruxism”. It leads to grinding down
of the enamel of the crowns of the opposing teeth. Often grinding of teeth is
done while the person is asleep at night. If left alone, there can be micro cracks
in the enamel and cavities that can cause infection of the pulp and lead to tooth
loss. The support tissues in the periodontal area can also be damaged leading
to loose teeth. Tense people who may have obsessive compulsive disorders, anxiety
disorders and other psychological or psychiatric problems would be at a higher
risk of developing bruxism. Treatment Bruxism
is treated by concentrating on not grinding the teeth during waking hours. This
will spill over to a certain extent into the nighttime hours. If not, a bruxism
guard at night may have to be worn, which are available over the counter in drug
stores and some sporting goods stores. Occasionally anxiolytics can be prescribed
for a short period of time, but on the long term this is not acceptable as they
are addicting.
Temporomandibular Disorder (TMJ disorder) The temporomandibular
joint (TMJ) is a joint between the jaw and the temporal bone of the skull. As
this image shows the mandibular condyle does not articulate directly with the
glenoid fossa of the temporal bone, but there is a donut like disc or meniscus
in between, which separates the TMJ
into an upper and lower joint component. Several conditions can cause jaw
pain (TMJ pain) such as osteoarthritis, rheumatoid arthritis, infectious arthritis
and several other medical conditions. Usually TMJ
pain or dysfunction is associated with pain centered around the TM joint
and in the teeth. But this image shows that it tends to radiate into the adjacent
areas of the head and neck. It tends to be multifactorial. There are dentists
who specialize in this very complicated field. The patient would be advised to
see one of these specialists, if the dentist has no readily available answers.
A myofascial pain syndrome can develop out of TMJ dysfunction, if it is not treated.
Symptoms There
is tenderness just below the external ear canal on the affected side. In pronounced
cases the jaw may move to the affected side when the mouth is opened. There may
be clicking and sometimes catching in the affected jaw joint. The patient may
get muscle spasm in the night from nocturnal bruxism. Myofascial pain syndrome
can occur in patients with normal temporomandibular joints. This syndrome is more
common in women that in men and has a peak in women ion their early 20s and again
around the time of menopause. More info: Temporomandibular
joint pain
Tooth Whitening and Cosmetic Surgery There is a branch
of dentistry that deals with cosmetic issues. Teeth are very visible when a person
smiles (particularly the front teeth). There can be gaps between the teeth that
are genetically determined. Other factors are from lifestyles such as smoking
that is one of the most common causes of discoloration of the enamel of teeth.
But aging and exposure to food pigments also leads to a yellowing of teeth. In
children whose mothers were exposed to tetracycline during the tooth forming period
in their pregnancy will have darkened teeth in the first set of teeth until the
age of 9 years. It is rare that the permanent teeth are affected. What are the
methods used? Tooth
whitening This can be used in the office
setting supervised by a dentist or at home by home treatment. Not every person
is a candidate for this and if you can afford the cost, the professional approach
may be best for you. Both approaches are very effective and are about equal in
the final result. If you had a lot of dental work done with different types of
fillings, the dentist supervised whitening may be best for you or the dentist
may advise that you are not a candidate at all. Keep in mind that any dental work
including crowns, fillings or repairs with porcelain, amalgam etc. will not whiten.
You may end up looking spotty as the normal enamel will whiten but the previous
dental work will stay with its color shade. A dentist will whiten your teeth for
upward of 1000$. The dentist uses 15 to 35 percent hydrogen peroxide gels and
combines this usually with high intensity light to expedite the bleaching process.
On the other hand the home whitening kits range between 10$ and 35$ per kit. The
over the counter preparations contain 10% of carbamide or hydrogen peroxide. Carbamide
breaks down in the mouth into hydrogen peroxide and urea, so essentially all of
the whitening action comes from the hydrogen peroxide. The stains from smoking,
from consumption of stained foods like red wine, black tea, coffee etc. or some
of the yellowing from aging will be bleached by putting the shine back on the
enamel crystals. Regardless of the method employed of the tooth whitening, the
effect will lasts for about 5 years. Long term studies have shown that the home
bleaching method using 10% of carbamide or hydrogen peroxide is the safest method
causing no harm to the enamel of the tooth. The more concentrated bleaching in
the dentist’s office can lead to porous enamel, which may cause dental decay
down the road, and it also tends to irritate the gums more. The dentist can counteract
the gum irritation with fluoride additions. Other products are whitening strips,
which are very effective and whitening toothpaste, which is about moderately effective.
Paint-on whitening, which consists of titanium dioxide is not very effective and
you may perhaps consider this a waste of your money.
Cosmetic Dentistry Some people were born with less
attractive looking teeth than others. There may be unsightly irregular gaps between
the front teeth or partially rotated teeth. Whitening will not take care of these
structural changes, but they often affect the owner’s emotional wellbeing significantly.
The cosmetic dentist can make a difference here. This has been well publicized
in TV series as “extreme makeovers”. No wonder, as the difference between
before and after tooth appearances can be as impressive as a facelift! Porcelain
veneers are the most popular ones of the cosmetic dentistry procedures. If teeth
are discolored or stained or if there are unequal gaps, these can all be remedied
with this procedure. It consists of porcelain wafers that are custom-made and
fitted usually for the upper six teeth. They are matched in color and shape to
the lower front teeth. The dentist removes the upper enamel layer of the teeth
to be veneered. Within two weeks during which the patient wears temporary veneers,
the custom made veneers are ready to be placed permanently. The cost per veneer
application is about 500 to 900 dollars per tooth, so for six teeth the bill could
be 3000$ to 5400$. Tooth
shaping When there are minor inequalities of height of neighboring
teeth, this can be equalized by shaving a small amount of enamel off the tooth
that is too long. This is tolerated well and only rarely leads to a slight hypersensitive
for a period of time, but this responds to prescription strength fluoride for
a period of time. The cost per tooth is about 30$ to 80$.
Tooth colored fillings There is more demand now than
in the past for tooth colored fillings. Technically this has become possible as
resin fillings now last a lot longer than in the past. It is particularly useful
in front teeth because of the appearance that blends into the natural tooth color
and because the pressures on a front tooth are not as high as on molars. However,
even in the back teeth resin fillings can be used for a period of time until a
porcelain crown is needed. Resin fillings are about 100$ to 400$ per tooth and
last about 5 to 7 years. They can be put in place within one hour (during the
same visit when the defect was assessed). Porcelain crowns likely last 15 years,
but are a lot more costly.
Resin-bonded bridge When there is a missing tooth
in the front row of teeth, a resin-bonded bridge may be the solution. Here is
a link that shows that the gap can be filled in with an artificial tooth made
of resin or porcelain and attached to the neighboring teeth from behind with wings
out of metal or resin. This dental bridge works well for front teeth where the
pressures are less than for back teeth where the forces from biting are too high,
so that there a regular dental bridge would be required. A resin bonded bridge
is about 1000$, a regular bridge about 2000$ to 3000$ and a tooth implant about
3000$ to 3500$. Illustration
of bridge |
