Sir, a new patient recently presented with a draining sinus between the 12 and 13 apices although they did not report any symptoms and were unaware of its presence. Sensibility testing confirmed a non-vital 12 and a periapical radiograph revealed what appeared to be two roots, surprising as there was no evidence of abnormal anatomy (Fig. 1). A further periapical was taken using the parallax technique which confirmed this.

Fig. 1
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Pre-op

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The patient was made aware of the guarded prognosis of the tooth, based on the bone loss and unusual root morphology. A CBCT was taken to assess the canal morphology and assess the viability of carrying out root canal treatment (RCT). This revealed one main root with one central canal with an additional root fused in the apical third, this did not contain any canals or communicate with the central canal. The scan also showed a palatal invagination in the coronal third. Based on these findings the patient was presented with the options of attempting RCT or extraction and they opted for the first.

The tooth was accessed, and one canal was found located centrally in the crown. Pus was found to be draining through the canal; necrotic pulp tissue was removed and copious irrigation with sodium hypochlorite was used throughout. Calcium hydroxide was placed between visits.

On return a few weeks later the patient reported no pain or problems and that the sinus was now gone. On re-access the canal was found to be dry, with no evidence of infection. It was cleaned and shaped to full working length using Wave One Gold rotary files, before a final flush through with EDTA. Elements Obturation Unit and AH plus sealer was used for warm vertical and backfill obturation. The post-obturation radiograph shows a well condensed root filling with flow of GP into the start of a lateral canal and sealer through the apical delta (Fig. 2).

Fig. 2
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Post-obturation

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The diagnosis was dens in dente, type 3a. Dens invaginatus has been defined as an invagination of the cingulum pit, with maxillary lateral incisors being the most common tooth affected. Prevalence has been reported between 0.3-10%.1 Oehlers classification system is widely used to classify dens in dente; type 2 and 3 often are challenging to manage with complex root canal morphology and should be referred to secondary care.

In this case, as we were able to take a CBCT which revealed simple root canal morphology, we were able to successfully treat in primary care. This report highlights the importance of looking out for dens invaginatus, prevention and early intervention and acknowledging that some of these cases may be less complex than anticipated, therefore may be able to be managed successfully by GDPs in primary care.