CBCT: Is “Big Brother” Watching Us?

There’s a new sheriff in town. And its name is the CBCT; (Cone Beam Computed Tom­og­raphy (CBCT)) the ultimate critical evaluator of quality endodontics.

For the past 100 years, the objective of dentistry has always been and always should be to maintain the natural dentition wherever possible. The objective of endodontic treatment has never wavered since root canal treatment was first performed; that being to prevent or treat apical periodontitis, such that there is complete healing and an absence of infection, while the overall long-term goal is the placement of a definitive, clinically successful restoration and preservation of the tooth.

The criteria for endodontic success is clear. The clinician must first find the canals and access the anatomy of the root canal system. Once found, the canals must be negotiated to their apices, the smear layer and biofilm removed and subsequent obturation and restoration must be achieved in a timely and effective manner.

With the emergence of exciting technologies, clinical endodontics is seeing higher successes never seen before.

Perhaps the greatest boon to our profession and a pivotal tool in the practice of endodontics is the use of cone beam computed tomography (CBCT). It is an accepted fact that conventional two-dimensional imaging has its limitations. Interpretation of a two-dimensional image of a three-dimensional object can make the interpretation of radiolucencies, complex dental anatomy and surrounding anatomic structures very difficult. CBCT technology, with its three-dimensional rendering ability, has allowed detection rates of root canal anatomy and detection of periradicular pathology to be dramatically increased. Although the detection of vertical root fractures is difficult at best with both conventional radiology and CBCT, CBCT has been shown to be an excellent supplement to conventional radiography in the diagnosis of root fractures. The differentiation between internal and external resorption, location and size, has allowed diagnosis and subsequent treatment to be more decisive and predictable. Unnecessary investigative treatment may now be avoided since three-dimensional evaluation of these ‘lesions’ can be achieved. The same pertains to the precise nature of a perforation and the role that CBCT plays on its subsequent treatment. Post-operative healing can be monitored more accurately with CBCT due to its superior resolution compared to conventional radiology and more ‘informed’ decisions can be made with respect to treatment planning.

But just because a CBCT, when interpreted, relays a ‘missed canal’, it doesn’t mean that it can be found or suggest that the clinician is inept, even with the use of the dental operating microscope and a sharp DG 16 endodontic explorer. Just because a CBCT, when interpreted relays the existence of a ‘lateral canal’, doesn’t necessarily mean that one exists – when in fact a vertical fracture may portray a similar bony pattern.

With all the technology available, we must still recognize that we are performing a biologic procedure on a human being. There are no guarantees. All that can be done is to reduce the possible technological variables that exist and provide our patients with the benefits of the latest and greatest in technique and technology. The only variable we have no control over is the human variable.

Will the information that the CBCT provides force the clinician to exhaust all efforts to find all the canals and subsequently address the anatomy? Will it force the clinician to elevate their efforts to provide a better debrided canal and a more thorough obturation? Is “Big Brother” watching?  I believe the answer to all of the above is a resounding “YES”!!

The future of endodontics is bright and holds incredible promise as we continue to develop new techniques and technologies that will allow us to perform endodontic treatment painlessly and predictably.

Research and development in the past has allowed us to be predictable in the present and has created opportunities for greater successes in the future. OH

Dr. Gary Glassman is the endodontic consultant on Oral Health’s editorial board. He maintains a private practice, Endodontic Specialists in Toronto, Ontario, Canada. He can be reached at gary@rootcanals.ca.