Richard Mounce, DDS
Bonded obturation has arrived in endodontics with Resilon from Resilon Research, Madison, Conn., and RealSeal from SybronEndo, Orange, Calif. The means to deliver a bonded obturation material has never been more convenient, ergonomic, or efficient with the use of the Elements Obturation Unit from SybronEndo, Orange, Calif. In short, these developments (especially bonded obturation) represent a quantum leap forward for endodontic capability.
Gutta percha traditionally has suffered from a significant limitation involving its inability to prevent the migration of bacteria or fluids in a coronal to apical direction. The clinical byproduct of this fact is that even the best cleansing, shaping, and obturation could not stop coronal microleakage, if the restoration was not placed (or leaked), allowing the existing gutta percha to be exposed to bacterial contamination. This problem, though not completely solved by bonded obturation, has been addressed to a significant degree. It now is possible to clear the smear layer from canal walls, apply a self-etching primer, and then follow with a sealer and soft core obturation points that allow the creation of a "monoblock" of resin obturation contiguous from the adhesive in the tubules to the canal core (filled with a soft resin material). RealSeal points look, feel, and handle exactly like gutta percha. The material is retreatable, dissolvable in chloroform, and can be used with the clinician's present obturation technique, be that warm or cold.
Bonded obturation is not possible with carrier-based systems at this time. The material is nonallergenic, nonmutagenic, nontoxic, and has been approved by the FDA. Studies have shown that RealSeal, in a statistically significant manner:
1) Reduces leakage in vitro
2) Renders a root less susceptible to vertical root in vitro fracture after obturation relative to the gutta percha
3) Reduces apical inflammation in vivo in dogs (If leakage in a coronal to apical direction is reduced, it makes sense that less bacteria are allowed to exit the root, resulting in less apical inflammation.)
I use RealSeal exclusively. For more information on RealSeal, consult the July issue of Oral Health from Canada.
As pointed out earlier in this article, the Elements Obturation Unit from SybronEndo is a major step forward in obturation economy, efficiency, and ergonomics. The unit combines and enhances the best features of the System B heat source (SybronEndo) and the Obtura II from Spartan, Fenton, Mo. In essence, it is possible to have a heat source to facilitate the downpack of the System B continuous wave of condensation and its backpack in a single piece of equipment. While a complete technical description of the unit is beyond the scope of this column, suffice it to say that it is possible to activate the tip of the heat source for no more than four seconds, allowing a wide safety margin so that the risk of overheating the root is diminished. After both five and 10 seconds of activating the heat button, there is an audible beep to inform the clinician that it is time for the separation burst and commencement of the subsequent downpack.
In addition, the Elements Obturation Unit is the only such device which is solely designed to both extrude gutta percha and RealSeal. The RealSeal cartridges are self-contained and allow maximum use of the material with no mess and no waste. Once the material is extruded out of the cartridge tip into the canal during the backpack, the needle on the cartridge backs itself out of the canal effortlessly. This machine puts a tremendous capability into the hands of the clinician at a very reasonable price. It achieves excellent results with techniques of all types and does not require carriers to be left in the canals. It also reduces the cost per tooth relative to carrier-based systems.
I would encourage clinicians to explore and try these materials at dental meetings. Give them a chance wherever possible. Having been a beta tester for the Elements Obturation Unit and now using RealSeal exclusively, the alternatives seem antiquated. I welcome your questions and your feedback.
Dr. Richard Mounce is in private endodontic practice in Portland, Ore. Dr. Mounce is the author of a comprehensive DVD on cleansing, shaping, and packing the root canal system for the general practitioner. The material is also available as audio CDs and as a Web cast pay-per-view. He lectures worldwide and is a widely published author. For more information, contact Dr. Mounce via email at comfort@MounceEndo.com. Visit his Web site at www.MounceEndo.com.