If you are interested in an endodontic refresher lecture, come and join me next Thursday at the Pacific Dental Conference (PDC 2019). Two and a half hours lecture filled with pictures and videos demonstrating the initial endodontic treatment.
Patient presents with apparent sinus tract in quadrant 4. According to the patient, the sinus tract had been identified by a hygienist during a hygiene appointment. Subsequently, the endodontic treatment had been initiated in order to resolve the infection. Here is a clinical photo of the sinus tract-like tissue.
The above image shows what appears to be a non-draining sinus tract. If this is indeed the case, it means that there should be a necrotic tooth with a lesion in close proximity to the drainage site and one should be able to express exudate from the site by poking it with a sharp explorer tip. Upon palpation, the tissue felt like a fibrous nodule that can be easily displaced under the non-keratinized tissue and it could not be drained with an explorer. Evaluation of available radiographs confirms lack of apical lesion in this area. Furthermore, the radiographs show significant pulp recession and heavy coronal calcification in all teeth. This could have resulted in false negative pulp vitality test results.
In the absence of periapical radiolucency and pain symptoms, one should not feel pressured to rush into treatment. The diagnosis for the above tooth might have been healthy pulp with normal apical tissues which would have required no treatment. Instead, the overall treatment has resulted in some structural compromise.
Patient presented with #1.3 pulp necrosis and chronic apical abscess. Due to missing #1.2, mesially tilted tooth #1.3 had been restored as #13-#1.4 splinted crowns in the place of #1.2 and #1.3. The clinical picture shows a ceramic interdental papilla which covers the root of tooth #1.3.
The key aspects in treating such a case are as follows:
The only non-precious stone that I know is the pulp stone. One of the factors contributing to root canal failure is remaining infected pulp tissue and the pulp stones, if left behind unnoticed, are the main reason for trapping tissue and retaining infection. Pulp stone removal is therefore a crucial factor in achieving a successful result in endodontic treatment. The following case shows how a large pulp stone can result in failure of a reasonably well done root canal treatment by trapping infected tissue, hiding the MB2 canal and retaining infection.
Proper access cavity (i.e. adequately large and at the level of the CEJ) in order to visualize the outline of the pulp stone/chamber floor is the key in removing it completely. In the above example the pulp stone is easily dislodged by troughing around it using a large diamond-coated ultrasonic tip and applying the energy directly to the calcified tissue. For demonstration and documentation purposes, no water was used in this case; however, it is highly recommended to use water for its cooling effect and in order to facilitate the debris removal.
If you attended my lecture at the Pacific Dental Conference last month, I mentioned “The Laws” that allow us to safely and predictably locate canals without being worried about mishaps (i.e. perforations, over-enlarged access cavities, etc.). One of the scenarios that we have to always be prepared for is accessing through a crown that is placed on a rotated tooth. One of the key elements discussed was the use of a probe to gain a better appreciation of the root outline at the CEJ level. The “Law of Concentricity” then allows us to start our access cavity preparation in the right direction.
The case below shows a rotated tooth #1-4 under a PFM crown. Preparing a typical access cavity in the Buccal-Lingual direction would definitely result in mishaps. Understanding the orientation of the tooth prior to the start of root canal treatment can result in achieving a safe and a conservative access prep. Note that even the rubber dam clamp wings are not good guides for the orientation of the chamber floor and for locating canals.
Sometimes when the conventional endodontic access is not possible, the unconventional approach can save the day.
A clinician should always aim at establishing a straight line access (SLA) in order to properly instrument, irrigate and obturate the canal system. Depending on the initial challenges, establishing a SLA could mean accessing an anterior tooth through its buccal surface [example below], accessing an anterior tooth through its incisal edge, or accessing a molar tooth through its mesial marginal ridge or its MB cusp.