Case Report: Treatment of symptomatic apical periodontitis

Dr. Lydia Harris, the third-place winner in the 2013 Young Endodontist competition in the UK, develops her endodontic skills for S-shaped root canals

This patient attended in pain from the UL5, and a diagnosis was made of symptomatic apical periodontitis. I was aware that the presence of an apical radiolucency, curved roots, and a heavily restored crown meant that the tooth had a guarded prognosis, but since the patient was keen to keep the tooth, we began root canal treatment. I placed the rubber dam, accessed the tooth, located the canals, patency filed, and irrigated. 

At the university, I had trained by using the step-back technique with K-files, and ProTaper^® hand files. I had starting using rotary instruments in my DF1 placement, and I attempted to use the rotary files to my corrected working length, but struggled to do so due to the canal curvature. I had struggled to get to grips with using rotary instruments in more curved canals, and I therefore returned to using the step-back technique and K-files. 

Upon obturation, I noted that something was awry, as the Thermafil^® (Dentsply Tulsa Dental Specialties) would not seat to length. I was aware that the GP was unable to negotiate the canal curvature, and a radiograph showed that the gutta percha (GP) was not at length, and some had entered the second canal.

In order to achieve a satisfactory result, I needed to remove GP using DMZ-IV and ProTaper retreatment files. This was my first experience of removing GP, and I was careful to ensure complete removal of the GP before re-preparing the canals chemomechanically. As I had evidently failed to sufficiently prepare the canals for GP the first time round, I spent some time enlarging the orifice using hand files and using EDTA to ensure that I could use the ProTaper files to length prior to obturation. I then obturated using Thermafil and have subsequently restored the tooth using a porcelain onlay.

An S-shaped curvature or double curvature can make a canal very challenging to negotiate. I learned that using hand files initially can help prepare the canal sufficiently prior to using rotary files. I now know to approach curved canals like these with more caution and to take time preparing the canals ensuring adequate mechanical preparation. I had never used retreatment files before, and I learned to use a pecking motion and ensure visualization of GP on the files. I now feel more confident in doing this and, therefore, am more able to attempt re-root treatment in the future.

I chose a porcelain onlay to restore the tooth as it provided excellent esthetics and cuspal coverage, and also helped preserve more of the buccal and lingual tooth present, which would have been destroyed had I chosen to perform a crown preparation. The tooth was in the patient’s smile line, and she was very pleased with the esthetic result. Overall, I was pleased with the end result of this root canal treatment and hope that the patient is able to retain this tooth for many years as a result.

I feel that this case helped me develop my endodontic skills overall as it involved improving upon a myriad of skills. First, my assessment of a case: I had not previously spent a long time analyzing the curvature of the roots, and the effect this would have on my method of root filling the tooth. Since this case, I have become acutely aware of the need to tailor my technique to the type of roots present, including ensuring adequate access, the need for anti-curvature filing, and the advantages and disadvantages of using rotary instrumentation in these cases. Second, it made me realize the importance of establishing the etiology of any problems encountered. I realized that, as my GP had not seated to length, I had evidently not prepared the canals adequately; and by establishing this etiology, I could therefore improve the outcome by rectifying this problem. I have also realized that acknowledging my own limitations and competency is key in endodontics; I was aware that the initial treatment I provided was poor, but that rectifying it may be difficult. I therefore ensured I informed the patient that I would try my best to improve on the root treatment, but that should it be beyond my competency, we would have to consider alternative pathways.

This case helped me improve upon my endodontic planning and also, the techniques involved in S-shaped root canals. It has encouraged me to realize that if an ideal result is not achieved initially, things can be improved upon and should not just be accepted. 

REFERENCES

1.Bergenholtz G, Horsted-Bindslev, P, Reit C. Textbook of Endodontology, Second Edition. Oxford: Wiley Blackwell; 2010.

2.Chong, BS. Harty’s Endodontics in Clinical Practice, Sixth Edition. London: Saunders Elsevier; 2010.