Steve Thompson presents a recent case study.
All too often patients present to the practice with infected pulp as a result of dental caries, cracked teeth or a loose filling. Luckily root canal therapy has a 90 per cent success rate if the patient is diagnosed early enough and the treatment is carried out to a high standard. Furthermore, the advent of high-performance products along with effective techniques means that dentists can more easily, safely and effectively treat patients.
This was the case with a patient with heavily restored dentition who presented to the practice for a routine examination after having not been to the dentist for several years. An examination revealed that the patient had cracks and secondary caries in multiple molar teeth, which had been treated with amalgam restorations 20 years previously. The UR7 was the worst affected with dental caries, so we decided to treat that tooth first. The plan was to create a core restoration in composite resin placed under rubber dam and then to consider a cast restoration due to the cracks and lack of tooth structure.
However, after the restoration the patient suffered from sensitivity to cold, so we decided to delay the cast restoration and the patient was monitored for further symptoms. Then, three months after the restoration was placed, the patient began to experience tenderness on the bite following a weekend of waves of pain in the area, signaling a complication. Through radiographs and an extensive examination, which revealed that the UR7 was tender to percussion and responded negatively to both Endo Frost and an electric dental pulp vitality test, the patient was diagnosed with irreversible pulpits followed by apical periodontitis.
One of the treatment options discussed was extraction followed by a possible implant, though further investigation revealed that the process would be very complex due the proximity of the roots to sinus. Alternatively, the space could have been left empty, but again this would have been less than ideal due to the risk of movement from surrounding teeth. The other possibility was root canal therapy followed by cast restoration, which both the patient and I agreed was the least invasive and more predictable treatment pathway with the highest chance of success.
Consequently, root canal therapy was carried out at a single visit under rubber dam with three per cent medical grade sodium hypochlorite used as the main irrigant. Preparation was completed using hand files and the size 25 tip variable taper HyFlex EDM one file system from Coltene. I chose to use the Hyflex files due to the moderately curved canals in this case. I used the ability to pre-bend to aid in accessing the canals of this upper second molar tooth without removing unnecessary coronal dentine. I particularly enjoy the feel of the files whilst they conservatively remove tooth structure.
Once the apical position was confirmed using an apex locator, a final rinse with ethylenediaminetetraacetic acid was carried out along with sonic activation and the canals were obturated with matched gutta-percha points and AH plus sealer. Finally, the access cavity was successfully sealed with a bulk fill composite, and the tooth is now ready for preparation for cast restoration.
All in all, I am very happy with the result and the outcome of the treatment, particularly as the curved and part-sclerosed canals, access difficulties and previous restorations and caries could have hindered endodontic success. The patient too was extremely pleased and relieved to hear that the prognosis is looking very positive, as they were made aware beforehand that it might not have been possible to save the tooth.
It just goes to show that while previous restoration issues and dental caries can lead to pulpal infection, the right approach using quality tools and an early enough diagnosis can ensure the affected tooth remains pain free and functional.
Fig 1. Pre-operative radiograph.
Fig 2. Post-operative radiograph.