Biocompatible Though Unretrievable

I have received a few calls and emails recently asking about sealers, particularly the “new” EndoSequence® BC Sealer. It has been marketed as “a revolutionary premixed bioceramic sealer which chemically bonds to both dentin and our bioceramic points.” So should you use it? Will it make your endodontic therapy better? And is it worth the additional cost? To answer these questions we should review what sealers do for us and what an ideal sealer would look like.

Sealers are the weak link of an obturation. They fill the space between the obturation core and canal wall. They also fill additional and irregular anatomy (unless warm vertical is used) and act as a lubricant. Leo Grossman outlined in his original text book the properties of an ideal sealer which seeks to add some additional properties to make our sealer a less of a weak link. These properties include tackiness (good adhesion), forming a hermetic seal, radiopaque, no shrinkage, no staining, bacteriostatic, biocompatible, slow setting, and retrievable.

To date no sealer available accomplishes all of these properties so when we evaluate a sealer we must prioritize. Among the top would be hermetic seal, bacteriostatic, biocompatible and retrievable. At first glance the ability to retrieve a material may seem less important until one considers leaving a fragment of a rotary file behind. As one of my great instructors would remind me, “we are imperfect in our treatment. Never put something you cannot easily remove if improvements are needed.” Additionally, obturations can become contaminated by recurrent decay or leaking restorations. If we cannot remove our obturation or sealer, then we limit our treatment options to surgery or extraction when non-surgical retreatment may have been very easy with a high prognosis.

I stress this point because while the BC Sealer is excellent in almost every category of an ideal sealer, it does not hermetically seal (though no sealer does) and there is no known solvent for its retrieval. It is Micro CThighly biocompatible and bacteriostatic, has good working properties, does not shrink or stain and forms a chemical bond to dentin to assist in sealing. However, this last point is also its pitfall. Use of this product makes non-surgical retreatment all but impossible weather it is to locate additional anatomy or re-clean an exposed obturation.

Alternatively, zinc oxide-eugenol sealers are biocompatible (will resorb if extruded with minimal periradicular irritation), are moderately antimicrobial, have low shrinkage, and is easily dissolved and retrievable. While there are more sealer types than time to review each one, each attempted improvement may yield higher scores in one area or another but “classic ZOE sealers” have the highest cumulative score and continue to be the gold standard of sealers.


Dr. Conn grew up in Langley where both his parents practiced dentistry. He completed a Bachelors in Chemistry at Simon Fraser University prior to receiving his DMD and Certificate of Advanced Graduate Study in Endodontics at Boston University where he wrote a thesis in clinical decision making and another in odontogenic stem cell differentiation. Dr. Conn maintains an active practice alongside Dr. Bittner while teaching as a part-time clinical assistant professor at University of British Columbia.

In his free time, Dr. Conn likes to attend the Seattle Seahawks games as well as participates in many outdoor activities.

On June 3, 2015, posted in: News for Doctors by