How to Manage a Dead Permanent Anterior Tooth - Thinking Long-Term

Severely damaged anterior permanent teeth in children and teens is somewhat common. This can be from a range of possible causes; such as trauma, developmental issues, macrodont teeth etc. In children and teens, these issues are far more complicated to manage, compared to adults, as commonly the anterior tooth is immature and only part way through its full development. This post will look at what options you have to consider when necrosis occurs in an immature permanent tooth.

Necrosis in an Immature Permanent Tooth

There are several possible causes for necrosis in anterior teeth, with trauma being the dominant cause. Proper initial diagnosis and management is paramount in ensuring that the tooth has the best chance of survival. However, despite our best efforts, some traumas have very high risks of necrosis.

A necrotic immature permanent tooth has many challenges and this includes;

  • Thin dentinal walls

  • Increased risk of root or cervical fractures (weaker)

  • Large open apex

  • Long-term requirement for success

    • 40 yr old VS 7 yr old

  • Compliance

  • Costs

So how can we manage this problem? Can we regrow the tooth? How do we obturate with an enormous apex? To treat a necrotic anterior tooth, we have 3 options.

  • Gutta Percha obturation (lateral condensation)

  • Regenerative Endodontic Procedures

  • MTA Apexification

Each option has pros and cons and this post will briefly review when it is best to do each one.

Traditional Obturation (Warm Lateral Condensation)

Anyone that commonly performs root canals is familiar with gutta percha obturations. An issue in an immature permanent tooth is how to obturate (A) with a HUGE apex and (B) with such a wide canal. Generally, we will do WARM lateral condensation when the apex is around #50 or less. Anything more than this commonly warrants a MTA apexification.

Necrotic #11 with PA pathology. How could you obturate this with GP?

Warm lateral condensation can help to avoid voids forming between the GP points in such a wide canal. It also saves you many accessory points! You do need a warm plugger and there is a particular technique to do it which we cannot cover in this post.

Prime point, this would be hard to condense well with cold lateral condensation

Post obturation with warm lateral condensation

Regenerative endodontic treatment/procedure

Regenerative endodontic treatment (RET or REP) is a more ‘experimental’ way to manage necrotic immature teeth. It aims to bring stem cells INTO the canal to ‘regrow’ the tooth .

This seems like such a great option! By regrowing the tooth, we can increase the strength of the tooth and avoid the possible fracture and failures that can develop in really immature teeth. Although the aims are really good, for a range of reasons, the evidence for its use in trauamatised teeth is relatively low. We think this is because the stem cells usually come from HERS, which are damaged in the dental trauma. Also from histological assessment, the ‘regrown’ tissues seen on radiographs are not actually tooth structure but a disorganised mass of cementum, bone and periodontal ligament tissues. So… does this actually improve the strength???? Until more evidence comes out, we wouldn’t advise this treatment at this stage.

Mineral trioxide aggregate (MTA) apexification

An apexification procedure aims to stimulate hard tissue at the apex of the tooth. Nowadays we use MTA over CaOH which was the only material we used to have available. It is technically a bit challenging as there are several steps involved. However, it is a very predictable procedure with high success rates.

Broadly speaking, the steps are:

  • Extirpation, chemo-mechanical preparation and dress with CaOH. Ensure your access is ‘straight line’ and NOT via the cingulum,

  • Ensure the infection has resolved with the CaOH dressing,

  • Re-access and irrigate and dry the canal,

  • Place MTA into the apex of the tooth with a small amount of bioceramic sealer,

    • Can use pluggers or paper points and try to condense several 2 - 3mm into the apex,

    • Take a CHECK PA and assess density. Repack if required,

    • Place at least 5mm of MTA into the apex and ensure it is well condensed,

  • Once you have the MTA placed, you can move on to thermoplastic obturation. You could do lateral condensation, but it is substantially quicker to do thermoplastic here.

    • Ensure the GP is below the CEJ to allow room to bleach the tooth down the track

  • Restore with GIC and CR!

Working length established. Take care with irrigation and such a large canal!

Initial MTA placed into the canal. Far from ideal placement and we need to get it further down to the apex.

MTA and thermoplastic GP. There has been a small amount of extrusion of the bioceramic sealer. I have finished the GP below the CEJ

Completed restoration. There are a few voids in the restoration, which is more of an ego bruise for me than a reduced prognostic outcome for the patient.

Conclusion

Necrotic immature permanent teeth can be a challenge to manage. There are a few options available to us to treat these quite successfully. Generally, an MTA apexification is a predictable and successful procedure when used in the correct cases. We are running an awesome online and in-person trauma course shortly in Sydney where we provide you with a step-by-step guide for how to do the above procedures.

Tim Keys