What is root canal retreatment?

Why a tooth may sometimes need further treatment after a root canal

If you’ve already had root canal treatment, being told that the tooth may need treating again can be particularly disappointing.

You might reasonably wonder:

Why didn’t the first treatment work?

Does the whole root canal have to be done again?

And is it worth trying to treat the tooth again?

Root canal retreatment – sometimes called endodontic retreatment – means treating the root canal system of a tooth that has previously undergone root canal treatment.

It can sometimes provide another opportunity to deal with a persistent or new problem and retain the tooth.

But it isn’t appropriate for every previously treated tooth.

Assessment comes first.

Why might a root-treated tooth develop another problem?

Teeth and root canal systems can be complicated.

The British Endodontic Society explains that further problems may occur for reasons including anatomy that was not treated during the original procedure, difficulties associated with the original treatment, or problems developing later.

Possible factors can include:

• complex root canal anatomy
• areas that could not previously be accessed
• changes affecting an existing restoration
• new decay
• cracks or other damage
• another problem affecting the tooth or surrounding tissues

This does not automatically mean that somebody carried out the original treatment badly.

The reason needs to be established in your individual case.

What happens during root canal retreatment?

Retreatment has similarities to initial root canal treatment, but there is an important difference:

The tooth has already been treated.

Before the root canal system can be treated again, Alex may need to gain access through or around existing dental work.

Treatment may involve:

1. assessing the tooth and previous treatment
2. accessing the root canal system
3. removing existing root-filling material where appropriate
4. locating and assessing the canals
5. cleaning, disinfecting and reshaping the root canal system
6. addressing appropriate findings where possible
7. refilling and sealing the canals
8. planning an appropriate restoration

The exact procedure depends on what is already present in the tooth and what Alex finds.

Why can retreatment be more complex?

Previous treatment changes the starting point.

There may already be:

• root-filling material
• a crown or other restoration
• a post
• altered tooth structure
• difficult or previously untreated anatomy
• an obstruction within a canal

Removing or working around these can make retreatment technically more involved than treating an untreated tooth.

This is one reason specialist endodontic assessment may be recommended.

What if there is a post in my tooth?

A post may have been placed inside part of a root-treated tooth to help support a restoration.

In some retreatment cases, a post may need to be removed to access the root canal system.

Alex provides file and post removal where clinically appropriate.

Whether removal is possible or sensible depends on the individual tooth.

What if there is a broken instrument in the canal?

Occasionally an instrument or part of an instrument may be present within a previously treated root canal.

This doesn’t automatically tell us what needs to happen next.

Alex will consider factors such as its position, the anatomy of the tooth and the reason further treatment is being considered.

In selected cases, file removal may form part of treatment.

In others, a different approach may be appropriate.

How does a microscope help during retreatment?

Alex carries out endodontic treatment using a dental operating microscope.

The microscope provides magnification and illumination, which can be particularly useful when working within a previously treated tooth and dealing with small structures or existing materials.

It is an important clinical tool.

It is not a guarantee that retreatment will be possible or successful.

Will I need a CBCT scan?

Possibly, but not automatically.

CBCT can provide three-dimensional information about a tooth and surrounding structures.

Alex may recommend a scan where that additional information is useful for diagnosis or treatment planning.

Evolve has CBCT scanning available within the practice.

Does retreatment mean the tooth will definitely be saved?

No.

Retreatment is an attempt to address the problem and retain the tooth where this is clinically appropriate.

No dentist or endodontist can guarantee that a particular tooth will be retained.

Before recommending treatment, Alex will consider whether retreatment represents a reasonable option.

Sometimes it doesn’t.

What are the alternatives to retreatment?

Depending on the tooth and the problem, alternatives might include:

• monitoring where appropriate
• apical microsurgery
• another restorative approach
• extraction

Not all of these will be suitable in every case.

The purpose of assessment is to work out which options actually apply to you.

What is apical microsurgery?

Apical microsurgery is a surgical endodontic procedure involving the end – or apex – of a tooth root.

It may be considered in selected situations where addressing the problem through conventional retreatment is not appropriate or where another endodontic approach is indicated.

It isn’t simply “the next treatment” after retreatment.

Read: My root canal hasn’t worked – can my tooth still be treated?

Do I need a referral for retreatment?

No.

At Evolve you can:

be referred by your dentist

or

self-refer directly.

Specialist endodontic care is provided by Dr Alex Brett, Specialist Endodontist, GDC no. 244328.

If you already have a dentist, you can remain with them for your routine dental care.

How much does root canal retreatment cost?

Specialist endodontic consultation – £x

Root canal retreatment – from £x

The cost depends on the tooth and complexity of the treatment required.

Following assessment, we’ll explain the treatment options and associated fees before you decide whether to proceed.

Questions patients often ask

Is retreatment the same as having another root canal?

It involves treating a root canal system that has already been treated, but it may be more technically complex because existing materials and restorations are already present.

Does needing retreatment mean my first dentist did something wrong?

Not necessarily. Problems can develop for several reasons and cannot be attributed to the original treatment without understanding the individual case.

Will my crown have to come off?

That depends on the tooth, the restoration and how the root canal system can appropriately be accessed. Alex will explain the anticipated approach after assessment.

Can a root canal be treated more than once?

Further treatment may sometimes be possible, but whether it is appropriate depends on the individual tooth and previous treatment.

What happens if retreatment isn’t possible?

Alex will explain the alternatives that apply to your situation. These may include another endodontic approach or extraction.

Key takeaways

• Retreatment means treating a previously root-filled tooth again.
• A problem after root canal treatment doesn’t automatically mean the original treatment was poor.
• Retreatment can be more technically complex than initial treatment.
• Existing posts, restorations and root-filling material may affect treatment.
• Specialist assessment helps establish whether retreatment is reasonable.
• Retreatment cannot guarantee that a tooth will be retained.

Concerned about a previously root-treated tooth?

You can arrange a specialist assessment with Dr Alex Brett without needing a referral.

Speak to our team about an endodontic assessment

Or read:

My root canal hasn’t worked – can my tooth still be treated?

For independent information, visit the ⁠British Endodontic Society.