A New Age in Endodontics

In January of this year the editor of the Journal of Endodontics, Dr. Ken Hargraves, announced the addition of a new category in the journal. Citing that 50% of the top 20 referenced articles in the last 5 years all came from the same topic, Dr. Hargreaves declared that Regenerative Endodontics will have its own section in the table of contents.  Recognizing the growing impact of a biological approach, there is tremendous hope that this will encourage the continued rapid research and enthusiasm comparable to that of the microsurgical advancements of the early 2000’s.

The inaugural article, Exploiting the Bioactive Properties of the Dentin-Pulp Complex in Regenerative Endodontics by Cooper et al (JOE 42:1 2016), was a comprehensive, synopsis of our current understanding and approach to regenerative endodontics.  In this article they cast the net of what defines regenerative endodontics around any procedure that is biologically based with the aim of pulpal wound healing.  The goal of regenerative medicine is complete replacement, in our case with a new neurovascular bundle capable of structural dentin formation.  Cooper suggests that a broader definition will allow for clinical patient-centered outcomes such as resolution of disease and tooth retention while developing more advanced treatments.  In other words, continuing the clinical practice of regenerative endodontics has been the foundation of our understanding and will be the source of our advancement even though we may not yet have achieved the narrow definition.

Cooper goes on to discuss how our understanding of dentin has moved beyond that of an inert connective tissue to that of a biologically active matrix.  We now know that there are over a dozen key growth factors that are embedded or “fossilized” within the organic matrix of dentin that play important regenerative roles.  Their liberation during early carious lesions is responsible for tertiary dentin formation.  This means we potentially have FREE autogenous growth factors, locally available, in the right proportions, if only we can predictably release them.

A major setback in the regeneration protocols has to do with the biological events required.  Cooper reminds us of the exquisite temporospatial control that is exercised during embryonic development.  Unfortunately during regeneration we not only lack this environment but we are also faced with pathologic agents and the associated immunoinflammatory sequelae that will undoubtedly disrupt signaling and, migration and differentiation. Throw into this problematic milieu the surgical intervention of irrigant and medicaments and the task before us certainly appears daunting.

Fortunately, stem cells appear to be “hardy” in so far as they appear to maintain their own microenvironment or niche.  It has been show extensively that there is a rich source of these stem cells in the periapical space in both adolescents and adults, and that they can be influenced, both in terms of chemotaxis and differentiation, by the growth factors in dentin.  Fully understanding, and perhaps promoting, chemotaxis and expansion of these stem cells will be a major focus of research going forward.

When it comes to differentiation of the stem cells, Cooper points out that this process is highly heterogenous.  Depending on the lineage of the stem cell, it has been seen that there are differences in the appearance and composition of the dentin that is deposited.  Determining the structural integrity and exercising control over differentiation to generate a more homogenous product will also be areas of intense future research.

Despite the formidable challenges that face true regeneration, the future appears bright.  At our current state we may possess an infantile understanding and application of this biological approach, but its power has captured our attention.  Successful endodontic therapy involves lowering intracanal bacterial levels to non-pathologic levels and retaining a functional tooth.  Exploiting the power of the immune system and harnessing the body’s ability to repair and regenerate opens the door to a new age in endodontics.

Dr. Jason Conn

Dr, Jason Conn, DMD, CAGS, FRCD(C)

ABOUT Dr. JASON CONN, DMD, CAGS, FRCD(C)LANGLEY ENDODONTICS

Dr. Conn was born and raised in Langley. He completed a Bachelors in Chemistry at Simon Fraser University before receiving his DMD and Certificate of Advanced Graduate Study in Endodontics at Boston University where he wrote a thesis in clinical decision making and another in odontogenic stem cell differentiation.

Dr. Conn has maintained an active practice alongside Dr. Bittner since 2012 while teaching as a part-time clinical assistant professor at the University of British Columbia.

In his free time, Dr. Conn is a Cub Scout leader, long distance runner, back-country hiker, snowboarder and yogi-in-training.

 

On April 25, 2016, posted in: News for Doctors by