Should endodontists do the coronal buildup after root canal treatment? If the GP trusts the endodontist to do the root canal treatment, why would he or she not trust the endodontist to do the coronal buildup? Why would an endodontist not want to do coronal buildups? All of these are good questions with no one simple answer but are worth closer examination.
My perception as a full-time private practice endodontist is that the vital importance of a postendodontic coronal seal is not as appreciated as it should be, and the rubber dam is underutilized. The endodontic literature is clear that clinical success is correlated with the placement of an excellent coronal seal (buildup and restorative treatment) after the root canal. Teeth with the coronal access sealed properly heal better than the alternative.
I am in favor of placing the coronal seal at the time the root canal is completed. If the case is treated by an endodontist, in my empirical opinion, the core buildup should be placed at this time. This has met with opposition from some referring doctors, primarily for financial reasons. The real question is what is in the patient’s best interest. Clinically, I think early coronal seal is the answer.
Irrespective of the quality of the endodontic treatment, the case is most likely destined to fail if the cotton pellet is left and a crown placed over it. Early coronal seal by the endodontist can avoid this. My practice is about 75 percent retreatment of failed root canals. Finding wet and odorous cotton pellets (aside from teeth that have lost their temporary fillings) is a common occurrence in failure retreatment.
Patients are genuinely frustrated (and rightly so) if they have to pay a second time to have otherwise good root canal treatment redone because their teeth were not sealed correctly the first time. I wonder how much higher endodontic success rates would be if this simple issue were taken care of properly instead of having it often be a turf issue between clinicians.
If the patient does not have the needed follow-up treatment, there is no absolute protection for the obturation against microleakage. This is true even with the significant advances that have been made in bonded materials and technique, such as RealSeal (SybronEndo, Orange, Calif.). The best possible seal is a dentin-bonded composite placed at the time of the endodontic completion, and done so under the surgical operating microscope.
Placement of the dentin bonding agent, such as Optibond Solo Plus (Kerr, Orange, Calif.), or Core Paste (DenMat, Santa Maria, Calif.), under the surgical microscope can be placed with precision and flow into the various ramifications of the access and into the canal a short distance. Performing this under the rubber dam will make a significant difference in preventing contamination of the root canal.
From the perspective of the specialist, once the endodontic treatment is completed to place a temporary filling in the tooth - only to have the temporary removed with loupes or the naked eye and be done so without a rubber dam - defeats the purpose of the original aseptic technique.
Any marginal gaps, voids or lack of integrity of the buildup, if placed in less than optimal circumstances, certainly are preventable. As such, it begs the question, “Why should they be left in this manner?”
My preferred clinical technique is to place the coronal buildup, as described, and remove the interproximal walls in order to “rough prep” the tooth. Then the referring doctor need only finish the prep, take an impression, and fabricate the crown. It is efficient for the patient, supported by the literature as valid, saves time for all parties, and ultimately is cost-effective because fewer teeth will need to be retreated. In essence, it is treatment performed with the patient’s best interest in mind. As always, I welcome your questions and feedback.
Dr. Richard Mounce lectures globally and is widely published. He is in private practice in endodontics in Portland, Ore. Among other appointments, he is the endodontic consultant for the Belau National Hospital Dental Clinic in the Republic of Palau, Korror, Palau (Micronesia). He can be reached at Lineker@aol.com.