Desperation Isolation by Martin B. Goldstein DMD

Occasionally, we’re called upon to perform a last ditch effort to salvage a badly decayed tooth. Such a restoration often involves performing endodontics on little more than a partially submerged root. Still, for whatever reason, the remaining fang offers some strategic advantage to justify the effort.

Perhaps it will prevent your patient from settling for a free end partial or it could be needed to lend added support to a fixed bridge. Whatever the reason for saving it, you could be faced with an endodontic candidate that presents a difficult isolation problem. Simply put, there’s no place for even your most angled rubber dam clamp to grab onto. A typical scenario might find you getting a clamp to “kind of” grab on, only to pop off as soon as a modicum of tension is applied when engaging the rubber dam. In the interim, you’ve managed to tear the gingivae sufficiently to bleed into your treatment zone, further clouding the issue. Now the signs of frustration begin to emerge as you become a bit frustrated with your assistant and your patient begins squirming a bit and begins to give you the ‘I’m worried about this’ look. And so, you begin considering to scuttle the rubber dam and attempt the root canal while managing an ever-present tongue, excessive saliva flow and bleeding tissue. In addition to all of this, you know you’re possibly running the risk of dropping a file. I’m sure you know the rest as unfortunately we’ve all been in a similar situation at some point in our careers.

In truth, there hasn’t always been a quick solution to this problem. I take pleasure in assuring you that this issue can definitely become a thing of the past due to the current crop of dentin bonding agents available to us today. Particularly useful, are the self-etching types that offer the convenience of lightening fast application. Currently, I use J. Morita’s One-Up F but you may have one that you feel more comfortable using. Combined with a stiff hybrid composite such as Caulk’s Esthet-X, relief is just moments away. (See figure 1) Here are the steps I take in this type of situation.

First, remove all tooth decay sans rubber dam. I prefer to use Ultradent’s Seekâ; a caries staining liquid that is easily applied from its syringe/brush applicator. You definitely need to make sure all remnants of decay are removed. (See figure 2) Bonding agents have little use for left over denatured protein. It’s convenient to complete your basic endodontic access prep while enjoying the unobstructed view.

Next, while cotton and mirror retraction keep the movable parts out of the way, I apply a generous coating of a self-etching bonding agent such as J. Morita’s One-Up Bond F. Self etching just means you won’t have to rinse and risk re-contaminating the bondable surface as is necessary when a two or three component system is employed. In addition, your patient won’t be exposed to the unpleasant taste of a conventional etching gel. The self-etching agent takes care of the etching and bond application in a single step that requires only one light cure. One-Up also changes color from pink to clear letting the operator know for sure that a cure has been effected. After twenty seconds of etch time, pop it with the light to set the bonding agent and you’re now ready for your hybrid.

As shown in Figures 3 and 4, syringe a wall of hybrid around the circumference of the remaining tooth, making sure to keep your access prep free of composite. The stiffness of Esthet-X makes this possible without the use of a matrix band. Just pat it into place with your favorite composite placement instrument. Esthet-X will not flow into an amorphous shape. It will retain whatever shape it was left in. It’s simply incredible!! You don’t need to get too fancy during placement, as you’ll be prepping this creation shortly.

Once in place and cured, you’re good to go. (See Figures 5 and 6) Amazingly, even a new rubber dam clamp (the kind that’s tough to spread) will not dislodge your wall as long as you did a reasonably good job of bonding to the tooth. Once your endo is complete, your isolation wall can serve as the matrix for a post and core buildup or you can level it and replace the buildup if desired. I typically retain it as part of my crown buildup.

While electro-surgical root exposure may also aid the cause, the method outlined here will usually get the job done in the shortest amount of time (and the least amount of bleeding). The time it takes to place the isolation wall will be more than offset by not having to deal with the oral distractions previously mentioned. You’ll also be free of the “what if I drop something” anxiety that occurs when working without a net.

When the root canal is completed, just throw some cotton “down the hole” and seal the wall with your favorite temporary material until the next time. Pictured here is Centrix’s Temp-It. (See Figure 7) If time allows, you can go on to complete the post and core in one sitting.

Thanks to today’s incredible bonding technology, “isolation desperation” is a thing of the past. One last thing, “if you haven’t tried Roeko’s Flexi-Dam, (the purple dam), you’ve yet to experience how easily a rubber dam can be placed. It redefines the word “stretch”. They are simply a “must have!”

Dr. Goldstein is a 1977 graduate of the University of Connecticut School of Dental Medicine and practices general dentistry in a group setting in Wolcott, Connecticut. He enjoys promoting the cosmetic side of his practice and has found it helpful to incorporate high tech methodology into his daily routine to accomplish this. Dr. Goldstein serves on the staff of Contributing Editors at Dentistry Today. He also contributes to Parkell Today, DentalTown and Dentistry, the UK’s version of Dentistry Today. Martin can be contacted at martyg924@home.com or at his office at 203-879-4649. He is available for speaking engagements on both digital imaging in dentistry and the use of high tech methodology to further the cosmetic practice.