- Root Canal Therapy
canal treatment is a dental procedure that replaces a tooth’s
damaged or infected pulp with a filling. The pulp consists mainly
of blood vessels, tissue fibres and some nerve fibres within the
hollow centre of a tooth. The procedure is also known as endodontic
for endodontic treatment are generally good. About 90 to 95 per
cent of patients who undergo root canal treatment can expect a
functional tooth after the treatment. The treated tooth should
last as long as the other teeth provided the person maintains
good oral hygiene and generally looks after their teeth.
Treatment: Preserving the Tooth
In the past, injured
or diseased teeth frequently had to be removed. Today, they often
can be saved through endodontic treatment. Also known as a root
canal treatment, this procedure may be performed by a general
dentist or a specialist called an endodontist. More than one practice
visit usually is required.
A root canal treatment
generally involves the removal and replacement of a tooth’s pulp.
The pulp is soft tissue containing blood vessels, nerves and connective
• The pulp is found in a canal that runs through the centre of
the hard tissue on the inside of the tooth (the dentin).
• The pulp extends from the pulp chamber in the crown down through
the root canal to the tip of the root in the jawbone.
• A tooth has only one pulp chamber but many have more than one
root and several root canals.
If pulp becomes damaged through injury or disease and can not
repair itself, bacteria and their products can leak into the pulp
and cause the pulp to die. If a root canal procedure is not performed,
an abscess can form at the tip of the root and cause considerable
pain. Even if there is no pain, the bone anchoring the tooth in
the jaw can be damaged. Without treatment, the tooth may have
to be extracted.
Treatment – What to Expect
Here is what you
can expect when you schedule endodontic treatment.
On the initial visit:
• Local anesthetic usually is given to maintain patient comfort.
• The affected tooth is isolated from saliva with a rubber-like
sheet called a dam.
• An opening is made through the crown of the tooth. The pulp
is removed and then the root is cleaned and shaped. Medication
may be added to the pulp chamber and root canal(s) to help eliminate
• A temporary filling is placed in the crown opening to keep saliva
out. Antibiotics may be prescribed if an infection is present
and has spread beyond the end of the root(s).
• The temporary
filling is removed.
• The root canal is filled and permanently sealed. (A metal or
plastic rod or post may be placed in the root canal for structural
If an endodontist performs the procedure, he or she usually will
send you back to your general dentist for preparation of a crown
to be placed on the tooth. Crowns are made from a variety of materials,
depending on the location of the tooth, the colour of the tooth
and the amount of natural tooth remaining. Discuss with participating
dentists which option is best for you.
is Up to You
The restored tooth
can remain healthy as long as its roots are nourished by the surrounding
tissues. Good oral hygiene at home and regular dental visits can
help prevent tooth decay and gum disease. If you take good care
of it, the restored tooth could last a lifetime.
A tooth is mainly
made of a hard material called dentine. Enamel is the surface
layer that protects the visible part of the tooth (crown). The
part of the tooth that sits beneath the gum-line is called the
root. The root is the ‘prong’ that helps anchor the tooth into
the jaw. Generally, front teeth have only one root, while molars
have several. There may be several root canals in one root.
The hollow centre
of a tooth is called the pulp chamber. This area contains the
blood vessels, nerves and pulp. The pulp is a sensitive tissue
that provides oxygen, nutrients and feeling to the tooth. The
main function of the dental pulp is to regulate the growth and
development of the tooth during childhood. The pulp extends from
the roof of the pulp chamber down into the bottom of each root
Once the tooth
is fully formed, nutrition for the tooth comes from the tissues
surrounding the root. Therefore, a tooth can function without
its pulp and, in the majority of cases, can be kept indefinitely.
After endodontic treatment, the tooth is ‘pulpless’, but it is
not a dead tooth.
A diseased tooth
pulp may cause inflammation or infection. The symptoms of a damaged
or diseased tooth pulp may include:
• Sensitivity to hot and cold drinks and foods
• Pain when biting or chewing
• Loose tooth
• Swelling of the gum surrounding the affected tooth
• Oozing of pus surrounding the affected tooth
• Facial swelling.
Sometimes, tooth pulp may become damaged or diseased without presenting
any symptoms. In these cases, the problem is usually diagnosed
by x-rays during a dental check-up or treatment for other dental
Some of the events
that can damage tooth pulp include:
• Deep-seated and untreated dental decay
• Decay beneath a filling
• Trauma to the face that damages a tooth
• Habitual tooth grinding (bruxism)
• Large and deep fillings
• Gum disease.
Research has also
found a link between cigarette smoking and root canal treatment.
A smoker is significantly more likely to need root canal treatment
than a non-smoker, but the reason for the higher risk is unclear.
dental treatment, complications could include:
• Spreading infection – once the pulp becomes infected, it loses
its ability to fight the spread of the infection. If bacteria
find their way into the pulp chamber, the bacteria will multiply
unchecked. This can cause a severe infection or an endodontic
abscess (a pocket or ‘blister’ of pus).
• Bone loss – the infection may spread around the tip of the infected
root canal and cause bone loss in the jaw.
• Loss of tooth – the tooth may have to be removed, which interferes
with the person’s ability to bite and chew. Tooth replacements
such as dentures or dental implants often require a lot more work
than root canal fillings.
The dentist examines
the tooth and takes x-rays. These x-rays also help the dentist
to plan for the root canal treatment by revealing the number,
size and depth of the roots.
You may need one
or more visits to complete the endodontic treatment, depending
on the complexity of the root canals in your tooth. The exact
procedure chosen by your dentist may differ from the procedure
outlined here. Ask your dentist for further information. Generally,
the typical root canal treatment includes:
• The procedure can be performed using local anaesthetic. If the
pulp is infected, anaesthesia may not always be necessary because
the tooth no longer has any feeling.
• The affected tooth is wrapped in thin rubber (called a ‘rubber
dam’) to keep the treatment area dry.
• The decayed portions of the tooth and any affected filling are
• The pulp or pulp remnants are extracted.
• The dentist uses a drill and small files to thoroughly clean
and shape the root canals to rid the canals of bacteria, pus and
debris. The root canals may need to be shaped or hollowed out
to ensure a smooth interior surface.
• The interior of the tooth is flushed with cleaning liquids and
• If infection is still present, the tooth is packed with special
medications and sealed with a temporary filling. You may have
to wait a few weeks, or even months, before the pulp canal is
filled. If the dentist feels bacteria are still present at your
next appointment, the cleaning procedure may be repeated and the
tooth once again packed with medication. This stage will continue
until the dentist feels the tooth is free from bacteria.
• The infection-free root canal is packed with a permanent filling
made of various materials. This is usually a rubber-based material
called ‘gutta percha’.
• The artificial biting surface of the tooth is fashioned out
of regular filling material.
• In severe cases where considerable amounts of dentine are removed,
the dentist may fit the tooth with a gold or porcelain crown to
help prevent breakage or cracking.
A tooth with a
healthy pulp is yellowish-white in colour. A pulp-free tooth may,
in time, turn grey. The dentist can advise you on appropriate
cosmetic dentistry procedures.
dentists can perform endodontic treatment
All dentists are
trained to carry out endodontic treatment. Some dentists will
refer complicated and emergency cases to an endodontist. Endodontists
are dentists who are specialists in root canal treatment.
care is needed, your dentist will discuss this with you. If you
would like a specialist opinion, ask your dentist for a referral
to an endodontist.