Unconventional Access Helps Save Tooth (Tricky Case)
A Case From Dr. Cameron Currie
A general dentist referred a patient to me because of deep carious cavities and the appearance of periapical radiolucency in tooth #26 FDI (tooth #14 using the US/Universal system).
Upon examination, I saw no soft tissue signs of infection/inflammation, and the tooth was not tender to percussion. It didn't respond to a cold test or electric pulp test, either. The periapical radiograph showed mesial and distal carious cavities very close to the pulp chamber that had been temporarily restored with glass ionomer. There was a large periapical radiolucency.
My eventual diagnosis was pulpal necrosis and asymptomatic chronic apical periodontitis.
The main challenge I saw from the radiograph was trying to preserve as much coronal structure as possible. A conventional endodontic access would de-roof the pulp chamber and remove the last bit of tooth structure joining the buccal and palatal tooth structure, weakening the structure significantly and increasing the risk of future fracture.
Straight-line access was achievable, but not in the conventional sense, because I used the mesial cavity as a large access cavity. The effective curvature in the distobuccal canal could have been reduced by using a more conventional access cavity geometry, but this would have been at the cost of precious tooth structure, and I was confident in the files I was using to overcome these challenges.
I located 4 canals: MB1, MB2, DB, and palatal.
In this case, I used size 6, 8, 10, and 15 hand files for initial scouting, working length determination, and early glide path development.
I used a hybrid system for the rest of the case – ProTaper Gold S1 for coronal flare and further development of a path – all in preparation for the WaveOne Gold Primary file, which I used as the master apical file in MB1, MB2, and DB canals. I used a size 25 hand file to confirm the apical size. The palatal canal was large and was prepared up to a ProTaper Gold F5. Apical gauging confirmed the master file.
I feel great confidence in these files while using my hybrid system. I love the coronal flaring achieved with S1 and its ability to negotiate curved canals easily. This makes the job of the highly efficient WaveOne Gold Primary file even more predictable. Using S1 first means I don't need the Primary file to prepare the whole canal, which would put more stress on the instrument and require more cleaning of flutes, more re-irrigation, and more recapitulation. Therefore, I feel I have established a highly efficient protocol.
Irrigation & Obturation
I used 5.25% NaOCl during canal preparation. 17% EDTA solution helped to remove the smear layer (activated by EndoActivator), followed by further NaOCl, and again activated by EndoActivator.
I obturated using matched GP cones for the master apical file. So for the buccal canals, I used the WaveOne Gold Primary Gutta-Percha cones as the master cone. In the palatal canal, I used a ProTaper Gold F5 Gutta-Percha cone. I used a warm vertical compaction technique for obturation.
By the end of the treatment, all caries had been cleared. The tooth was restored with a posterior composite restoration.
Finally, I referred the patient back to his GP for provision of a cuspal coverage restoration.
About Dr. Cameron Currie
Dr. Cameron Currie graduated from Bristol Dental School in 2007. Following further study and examination, he was awarded Membership of the Faculty of Dental Surgeons by the Royal College of Surgeons, Edinburgh in 2011.
In 2013, he successfully completed a two-year diploma in Endodontic Sciences at the world-renowned UCL Eastman Dental Institute. He continues his studies in this area and has completed training in the U.K. and abroad.
Cameron's clinical practice is limited to endodontics and he takes referrals from dentists within the practice and also the surrounding area.
Cameron is an empathetic dentist who does his utmost to put patients at ease and ensure they are comfortable and relaxed throughout all stages of treatment.