Don’t Want to Hear That!
IN THE WORLD of endodontics, there are certain words that you really don’t want to hear. You know, for example, when your wife says on a Sunday afternoon, “Honey, it’s your service on the phone!” Or when a patient sees the rubber dam and says “Oh no, you can’t possibly use that. I am an extreme gagger.” Or “Do you accept insurance, and what do you mean there’s a copayment?”
Now from a practical and clinical standpoint, endodontically speaking of course, the words calcified canal bring up a few primordial feelings. The term calcified canal in reality is a general catch phrase that has come to have multiple meanings. Does it mean that you can’t see the canal on the radiograph? Sure, why not! Ah, yes, but is the canal totally calcified or partially calcified? If it’s partially calcified and actually clinically negotiable, then it’s really a calcifying canal, not actually a calcified canal. Not being able to visualize a canal on a radiograph or CT scan does not necessarily mean that the canal is not negotiable to the apex. It just means that access and treatment might be a bit nightmarish, particularly for those not equipped with the proper instrumentation to do the job properly.
So what equipment do we need to arm ourselves with? To do the case properly, you first need an adequate road map to plan your trip. Obviously, you have taken a periapical radiograph. Certainly a CBCT of the tooth couldn’t hurt. A three-dimensional scan of the tooth will certainly give you insight into anatomy that you never could have assessed from a two-dimensional radiograph—insight that will be invaluable both preoperatively and, sometimes more importantly, during the treatment. Using the CAT scan, you can look at root angulations and cross-sectional anatomy that you could never see before unless the extracted tooth was sitting on the countertop in front of you! During treatment, the CT will show you where your buccal-lingual excavation is heading in relation to the tooth anatomy and canal location. OK, what else? Well, you better have good magnification. Loupes, illumination, and a microscope are a must. Magnification is the only way to see the calcific deposits on the pulpal floor.
It is important to understand the dento-legal and standard-of-care expectations that you are subject to as a general practitioner. Standard of care is set by the specialist, and that is the dento-legal expectation. Since that is the case, if the endodontist has a microscope to look for calcified canals, then you also should have one. If as a GP you assume dental responsibility for the diagnosis and treatment of a calcified tooth, then in this day and age of dentistry not using a scope and just stating that the canals are calcified will not justify your not getting to the apex.
Enough of the medico-legal B.S. and reasons to refer a case with calcified canals. On to the clinical nitty gritty.
Let us say that you have access to a scope and CT and you’re ready to roll. What’s next? Based on the road map you’ve plotted, it’s time to gain access. When doing so, it is so important to be aware of external anatomy and how deep you can drill before you violate it. So measure the distance to the furcation in molars and keep the cervical profile of the tooth clearly in mind. Use the PulpOut Bur® if you need to, which will help in the process. Be very careful that the rubber dam and clamp don’t obscure your orientation. If you’re gaining access through a crown, watch out for skewed angulations and rotations. To make sure you stay on target, don’t be shy about taking radiographs—take an additional two or three if you have to. You can use a sharp explorer placed in the tooth to mark the point of excavation more accurately on the radiograph. Sometimes it is necessary to continue the access process without the rubber dam in place just to maintain orientation. At other times, you can clamp a tooth behind and drag the dam to a tooth in front to have a clearer view in your mind’s eye.
Once you have achieved the chamber-floor level, look for the calcified canals. Under scope light, they will appear white surrounded by darker dentine; under transillumination, they will appear darker. Excavate with an ultrasonic file, or use a Muntz bur in a slow-speed handpiece. Use ETDA in the chamber to clear it of debris and provide a clearer picture of what the pulpal floor actually looks like. As the excavation gets deeper into the roots, a second CT scan may be necessary to make sure that you are properly aligned within the buccal-palatal or buccal-lingual dimensions of the root. Look for one canal at a time. Many times finding the first canal will give you the orientation that leads to finding the second and so on and so on.
Unfortunately, a severely calcified case can be frustrating and certainly economically not as rewarding due to the fact that they usually involve multiple visits or much longer appointments. Hey, it comes with the territory. Thus, if you feel that you want to give up and say “Done, finished and calcified,” think twice. If the patient has a problem and ultimately seeks a retreatment and the “calcified” canals are treated, that may eventually become a liability if the stuff hits the fan. If you choose to embark upon the proposed treatment path, the standard of care is “if the specialist can do it, then you should be able to do it.” Everything must be considered when it comes to planning our patients’ treatment. Making the decision to refer a complicated case emphasizes the general dentist’s treatment expertise and understanding of what may be best for the patient. This in turn can and certainly will enhance the relationship between patient and dentist, which I am sure we all know is invaluable in every way.
Thus, I now present some “calcified, tough, multiple visit, not too economically productive, back ache producing, oy vey do I wish I could be doing a simple bicuspid” root canals. Hope you enjoy the show.
April - June 2012