What is root canal treatment?

Root canal treatment is a procedure whereby the diseased pulp tissue of the tooth is removed and the resultant space filled with an inert root filling material which seals off its communication with the bone. It prevents the spread of infection from the tooth to the bone.

The process of root canal treatment involves the following steps:

A. Evaluation for treatment

The dentist examines the tooth to ensure its structure is not too weakened for biting. An x-ray of the tooth is taken to assess the extent of the decay and the degree of infection in the supporting bone.

If the tooth is deemed restorable, the dentist will discuss with you the risks and benefits of treatment and obtain your consent before proceeding with treatment.

B. Root canal treatment

The tooth is isolated by draping a rubber sheet over it to prevent secretions in the mouth from contaminating the area. The rubber sheet also helps to prevent cleansing solutions used during treatment from entering your mouth and causing irritation to your oral tissues.

An access cavity is made in the tooth through which cleaning and shaping of the root canals of the tooth is carried out with the use of rotary or hand held instruments.

The resultant cleaned root canal space is filled with a rubber-like material called “gutta-percha”. It seals the internal part of the tooth from the bone.

Root canal treatment is now completed. However, the tooth has been “cored out” and is hence structurally weaker.

C. Restoration of the tooth structure

There are 2 portions, the internal and the external structures. A filling restores the internal and external structures in continuity. A post may be inserted into the canal of the tooth to aid retention to the filling. Where there is a possibility that the tooth may fracture under the constant stress of biting, restoring it with a crown externally provides an all-round protection that reduces the possibility of it fracturing.

Commonly Asked Questions

1. What are potential risks and complications of root canal treatment?

The treated tooth may have some pain and tenderness to biting/touch for a few days to a week after treatment.

Possible complications that may happen during root canal treatment include instrument fracture and root perforations. Chemicals and medications may also escape out of the root and cause irritation to surrounding tissues, which could result in pain, sensitivity, swelling or numbness.

2. Is root canal treatment always successful?

Success rate of non-surgical root canal treatment is around 90%. It is lower in cases where pre-existing infection has extended into bone surrounding the root apex, and in cracked teeth. Failure is usually the result of continued infection, loss of bone support, propagation of cracks in the tooth and root fracture.

3. What will be the next step if root canal treatment fails?

In the event of failure of non-surgical root canal treatment, surgical treatment (apical surgery) may be considered if conditions are feasible. Otherwise, the tooth will have to be extracted. There are various replacement options such as a denture, bridge or implant which you may like to discuss with your dentist.

When is root canal treatment required?

Our teeth are vital structures nourished by an internal core of tissue consisting of nerves and blood vessels. It is called the "pulp" of the tooth.

Root canal treatment is needed when the pulp tissue of the tooth becomes damaged or infected when bacteria is allowed to penetrate into the pulp. This can happen due to deep decay, cracked tooth or tooth fracture. Dental trauma may also disrupt the nerve and blood supply to the pulp, causing the tooth to become "dead". A tooth with an inflamed or infected pulp may cause pain, swelling and pus discharge through the gums.

What is root-end or apical surgery?

In certain cases of failed non-surgical root canal treatment, apical surgery can be performed to help eliminate the persistent root-end infection. A surgical flap is raised to move the overlying gums away and the infected root tip is resected and removed together with the surrounding infected tissues. The resected root end is then cleaned up and a biocompatible root-end filling is placed.

Post-surgery, some pain and swelling around the surgery site may be expected for a few days to a week. Painkillers and antibiotics will be prescribed as necessary. A review is scheduled usually about one week later to remove the stitches and check that the surgery site is healing well.

Whitening of discoloured root-treated teeth

A tooth with a necrotic pulp or a previously root-treated tooth may be discoloured and patient can find this unsightly if it involves a front tooth. Compared to a full-coverage crown, internal or non-vital bleaching serves as a more conservative and less expensive method to correct tooth discolouration.

Root canal treatment or re-treatment is performed to treat root-end infection if it is present. Thereafter a bleaching agent is placed inside the tooth and sealed with a temporary filling to allow it to gradually exert its effect and whiten the tooth. Multiple applications of the bleaching agent may be required as the amount of bleaching agent that can be placed inside a tooth is limited.

A small degree of reversal of the discolouration may be expected a few years after internal / non-vital bleaching of the tooth.

What can I expect after root canal treatment?

Root canal treatment has been performed on you.

You may experience some discomfort from the tooth after the treatment. This usually comes in the form of biting pain and tenderness to touch/pressure, and may last for a few hours to a few days.

Swelling of the gums and/or mild swelling of the face may occasionally occur, but this should resolve over the next few days.

Remember to take medications if they have been prescribed.

It is important for you to know that the tooth following root canal treatment is structurally weak.

To avoid fracturing the tooth or the temporary filling, you are advised to refrain from biting on the tooth.

You are advised to contact the clinic if the filling dislodges or you experience severe pain or swelling.

Otherwise, please keep to your appointment. Should you require a change in appointment, please call 66022828 at least 48 hours in advance.