Over the past 30 to 40 years, endodontics has undergone a wholesale makeover. It has gone from a treatment mode in which success was uncertain, to a procedure whose long-term success rates are at least as good (if not better) than most dental therapeutics. This has come about through two different research avenues that have converged: (1) the clinical and (2) the biological.
After its certification as a recognized specialty, endodontics focused on attempting to combat the problems of the erroneous focal infection theory, the perception that treatment was painful and the need to elevate the level of clinical endodontics through the understanding of the anatomy of the root canal system. But just how "sterile" did the canal system need to be before the canal could be filled? The answer was unclear. Once it was understood that success could be achieved reliably and predictably by adhering to certain fundamental principles (the Rationale of Endodontics), our attention focused on the actual clinical methods of achieving those goals. It required clinicians to fully clean and shape and obturate the canal system while at the same time recognizing the role of asepsis in achieving those goals. Recognition of these factors demanded a higher standard of clinical care from clinicians. Less emphasis was placed on culturing and the need to prove to our physician friends that infected canal systems were not the cause of other systemic problems.
INFLUENCE #1 - PHILOSOPHIES OF TREATMENT
Better understanding and visualization of the anatomy of the canal system led to less missed canals and higher success rates. The movement toward thermoplasticized gutta percha methods of obturation led to better seal. More recently, more flexible Ni-Ti based instruments have allowed for easier negotiation of difficult canal systems. Different irrigating solutions and methods for activating them enhanced the effectiveness of these procedures by not only lubricating instruments and dissolving tissue; they also assisted in reducing the levels of bacteria present in the prepared canal space. Better-shaped canals were cleaner, easier to fill and more successful. As the reasons behind endodontic success became clearer, Endodontists began focusing less on why endodontics succeeds and more on why certain cases fail. Again, was it our lack of ability to clinically handle these cases (tissue/bacteria left in inaccessible spaces)? Or was it due to pure lack of "sterility" of the canal system (a particular bacteria in the canal system, bacteria in dentinal tubules etc)? As in many areas of dentistry, the cry arose for "Evidence Based Treatment". We could no longer use the "works for me" argument when discussing endodontics. Over the last 20 years or so, two groups emerged that had different answers to these questions.
On the ROOTS internet forum (see info on how to become part of ROOTS on the bottom of the page), the controversy has crystallized and these two groups have been given the name:
1. The Apical Barbarians - given that name because of their apparent lack of "sanctity" for the "holy" periapical space.
- Believe in the merits of clinically cleaning, shaping and sealing the canal space to its full length.- are not "afraid " of not having strict sterility in the canal because they believe in the adequacy of their overall clinical technique in rendering the canal space inhospitable to bacteria that cause Periradicular infection
- Appreciate but have less concern for the bacteriology. Consider medication such as CaOH an adjunct, but not necessary in treatment of all necrotic cases.
- Are primarily clinically influenced. Leading proponents are US based ie/ Ruddle, Buchanan, Schilder
- Favourite reaction to their opposing group is: "The research was poorly done. The human clinical cases were awful and not representative of proper endodontic clinical technique. They would heal if done properly. "
- Generally perform very high quality clinical endodontics (radiographically)
- Are comfortable with the ideas of apical patency (they believe it is important to prevent canals being blocked), they do not mind occasionally passing a small instrument through the apex to do this, some fill to the radiographic apex (which is technically "long") and have no qualms with limited sealer "puffs" during obturation.
- Have infrequent failures mostly associated with necrotic teeth. They don't mind doing surgery in these rare cases - and realize that these failures are likely due to the limits of the instrumentation in achieving the clinical goals of treatment (ie/ adequate cleaning and shaping).
- Many perform single appointment treatment on all vital teeth and occasionally even on necrotic teeth, depending on the case.
2. The Pulp Lovers - given that name because of their reverence for the "sanctity" for the "holy" periapical space.
- Believe in the merits of keeping instruments inside the confines of the root at all times.
- Are "afraid" of not having strict sterility in the canal because they believe it is impossible for any clinical technique (without the use of multiple appointment intracanal CaOH medication) to consistently render the canal space free of the bacteria that cause Periradicular infection. - Are very concerned about the bacteriology. So much so that they would NEVER consider treating a necrotic case without placing CaOH in the canal for weeks or months at a time prior to obturation. (depending on the case)
- Are primarily research influenced - have NO faith at all in non 'Evidence-Based" studies without controls and strict scientific protocol. Leading proponents are European (Primarily Scandinavian influenced) research based academics.
- Favourite expression - "Show me the research. Your perception of your clinical treatments is unsupported and wrong."
- Generally perform clinical endodontics that are radiographically "short" but justify this by saying that they prefer not to "violate" the periapex.
- Are uncomfortable with the idea of apical patency, they hate passing any instrument through the apex, never fill to the radiographic apex (which they consider to be extrusion of foreign material) and disdain those with even limited sealer "puffs" during obturation because these cause Periradicular inflammation and less healing than their "short" fills.
- Will never perform single appointment treatment on necrotic teeth but do believe that vital teeth can be treated in one appointment.
In time, I predict that there will be a convergence of these two groups. We have begun to see that on ROOTS. There may still be philosophical differences in the methods of treatment but the goals of treating Endodontic Periapical Periodontitis remain the same for both groups. The challenge will be to find a way of incorporating private practice clinical results in a manner that satisfies the research based protocol. Although private practitioners may never be able to use their daily cases in "pure research" (because they have no clinical "control cases" to compare them with), digital technologies and a standardized reporting format may offer a way to have them incorporated into a "super database" compete with images. This may allow for at least rudimentary comparison of clinical results on a huge scale.
INFLUENCE #2 - MONEY
Whether we choose to recognize it or not, Dentistry is big business. When the FDA in the United States allows a drug to be introduced, it must have undergone extensive animal and human tests before it can be distributed to the public. Unfortunately, many of the techniques, methods and materials in our profession are not as highly regulated as those in the drug industry. It is possible to introduce, market and sell virtually any technique to dentists, as long as it does NOT introduce a new material or drug. Many of these new products and techniques are introduced into the dental marketplace without any unbiased unaffiliated scientific studies to support them. One example is the new Kerr K3 rotary Ni-Ti Endo file. While there is no doubt that the file is different in design than others on the market, there is no currently published research to support the claims of the manufacturer as to its being "better". Yes, in time I am sure there will be lots of research on this file, but it will only come after millions of dollars worth will be sold both in N. America and around the world. " Launch first, research later" seems to be the rule in Dentistry. It is even more confusing when we find spokespersons/clinicians have been hired by or have spoken in favor of one product at one time, only to be lured away by better endorsement fees contracts, or financial arrangements with a competitor.
Be careful what you read. Dental trade publications (DPR, Dentistry Today, etc. aka bathroom reading) are not a good source for unbiased information because they are not refereed. (I suppose this publication could be classified as that as well!!) Be aware of the writer's financial affiliation with the product or company. Remember that Universities/Department Heads also have their own axes to grind and grants to receive. It is unlikely that a graduate student will be able to publish research that is not in agreement with the person signing the Thesis! The researcher's bias as an Apical Barbarian or a Pulp Lover will likely influence their methods and conclusions. The amount of truly "independent, unbiased, pure research" that deals with clinical topics is truly very small. When in doubt, check with your Endodontist. As a person who understands the money, politics and science of endodontics, he is in the best position to give you some perspective as to how a technique or product may benefit your practice. After all, should you have problems with that brand new "gizmo/method", he is the one who will have to deal with the retreatment scenario should you obtain less than optimal results with your patient.