Master Class

PART V: How and Why Substandard Endodontic Treatments Fail:
The Importance of Investigating and Ruling Out Cracks Prior to New Treatment Planning

Preview Only, Purchase Required For Full Program Access.

Effective Date: September 1, 2017
Expiration Date: August 31, 2020
Format: Self Instructional - Audio Visual Voice-Over with Slides
Estimated Completion Time: 4.5 hours
Credits: 4.5

Getting Started

Read all the information presented below. When ready select the Introduction or appropriate tab above.

Program Summary

In the introduction of the program, the author reveals an alarming 24%-60% global prevalence of Apical lesions in teeth with inadequate root canal treatment. The literature’s histopathologic term used in describing these lesions is Apical Periodontitis. (AP). The statistics are alarming because the “Standard Normal” prevalence of Apical lesions in endodontically untreated teeth is 1½% - 7%.

This program stands for the management of teeth with substandard endodontic treatment failures because of the evidence-based relationship between abusive endodontic treatment, and root structure cracks initiation and propagation. Abusive endodontic treatment is one form and a principal cause of substandard endodontic treatment. More on this relationship discussed in part III of the master class series.

The program is composed of seven chapters planned to include the most clinically relevant facets of the inadequate or sub-standard endodontic treatment.

Chapter One Tells the story of misdiagnosing of a failing substandard endodontic treatment as periodontitis. Analyzes the complications and shows the importance of proper diagnostic investigation.
Chapter Two Review of the current definitions and terminology used in describing endodontic apical translucencies.
Chapter Three Discuss the most important studies on the factors influencing endodontic treatment success or failure.
Chapter Four Identify the factors, materials, methods and clinical practices that promote quality treatment, prevent, and heal Apical Periodontitis.
Chapter Five Examine the factors, materials, methods and clinical practices that result in substandard endodontic treatment and development of Apical Periodontitis.
Chapter Six How to use the 4ROD protocol to investigate substandard endodontic procedures, identify the cause of the failure and rule-out cracks.
Chapter Seven Introduces nonsurgical and surgical interim endodontic therapy to eliminate large Apical Periodontitis Infections, regenerate native bone and prepare the sites of hopelessly fractured teeth for implant placement.

Pulpal necrosis and substandard endodontic treatment are the principal causes of Apical Periodontitis. Mechanical root canal preparation is an integral part of modern endodontic practice. The improper use of mechanical or manual endodontic instruments causes root canal ledging, stripping, perforating and instrument breakage. These errors cause incomplete root filling which is the leading cause of substandard endodontic treatment outcomes. Collectively about 80% of endodontic treatment failures are contributed to root canal preparation errors.

To correct canal preparation errors, the clinician uses manual, mechanical tools and gadgets to bypass a root canal ledge or broken instrument. The generated forces associated with these attempts may initiate within the root canal surfaces micro cracks or propagate existing ones. The clinical complications of these cracks usually manifest months or years following endodontic treatment and post placement completion.

Therefore, regardless of the patient signs and symptoms, the radiographic diagnosis of a tooth with substandard endodontic treatment, should be considered a dental treatment risk factor. The clinician should investigate the tooth when considering endodontic retreatment or plan to use the previous root canal filling as a foundation for a post placement or new restoration.

Chapter 6 outlines the procedural protocol to follow when treating patients with substandard endodontically treated teeth. The clinician’s objectives are:

  1. Establish a doctor–patient relationship based on considerate interaction especially when the patient is unaware of having an iatrogenic dental problem.
  2. Identify and correct the cause of the substandard treatment.
  3. Rule out the presence of line cracks in the pulp chamber or the clinical crown before endodontic or restorative retreatment.
  4. Prevent tooth crack propagation thru changing the treatment protocol to atraumatic endodontic and restorative retreatment.

The program contains advanced specialty knowledge that enhances the clinician diagnostic and treatment skills. The general practitioners need such knowledge because they perform 72%- 88% of endodontic treatments services provided in the USA and Canada.

Chapter five discusses the role of the dental school as an important influencing factor in resolving the problem of substandard endodontic treatment. Endodontic curricula must have additional instructional hours’ time. Need to focus on more relevant content presented by full-time endodontic faculty committed only to the undergraduate curriculum and advanced continuing education courses to the general practitioners.

This program offers concepts, methods and guiding principles based on evidence, and tested clinical practices. The goal is to enhance the clinicians understanding of endodontic treatment diagnostics and the relationship between endodontic treatment and tooth structure cracks.

Target Audience

The target audience for this course is Dentists and Dental Specialists from novice to advanced. No prerequisites required.


Marwan Abou-Rass DDS. MDS. Ph.D

Marwan Abou-Rass DDS, MDS, Ph.D

Professor Emeritus,
Herman Ostrow School of Dentistry
University of Southern California

Dr. Abou-Rass brings nearly fifty years of cutting edge innovations in the field of endodontics and dental education. He pioneered the concept teaching molar versus central teeth as the best sequence for learning endodontic skills and developed the critical error approach to clinical performance evaluation.

In clinical endodontics, Dr. Abou-Rass has made a number of significant new concept and methodology contributions including:

  • Stressed pulp concept
  • Anti-curvature filing method
  • 4R Operational Diagnosis Protocol
  • Composite Post and Core buildup protocol
  • Endodontic Treatment Finalization Protocol
  • Interim Endodontic Therapy for native bone regeneration before implant placement

In addition to his DDS, Dr. Abou-Rass holds a Master’s degree in Dental Science in Prosthodontics , a certificate in Endodontics and a Ph.D., in Higher Education from the University of Pittsburgh, Pennsylvania. Dr. Abou-Rass served as Endodontic Department Chairman and Director of the Advanced Endodontic program at the University of Southern California, School of Dentistry (1971-2000). Dr. Abou-Rass moved to Riyadh, Saudi Arabia in 2000, where he directed the AEGD program at PAADI from 2000 to 2012.

Currently he is USC Professor Emeritus and publisher of Dental Economics MENA Journal and

Educational Objectives

Chapter One
  1. Recognize the complications of Overlooking or Misdiagnosing substandard Endodontic Treatment failure.
  2. Show the importance of Positive patient – doctor rapport especially whenTreatment difficulties or complications occur.
  3. Avoid using the cracked tooth excuse to conceal a diagnosis or treatment error.
Chapter Two
  1. Use the endodontic specialty definitions and terminology in describing the different clinical endodontic apical translucencies.
  2. Identify Apical Periodontitis (AP) as a destructive bacterial disease.
Chapter Three
  1. Discuss the findings of the three most significant success and failure studies in endodontics.
  2. List the pre, per and post treatment factors that influence Endodontic Treatment outcomes.
  3. Classify substandard Endodontic Treatment failure factors into endodontic and non-endodontic.
Chapter Four
  1. List the factors that promote quality Endodontic Treatment.
  2. List the principal endodontic anatomy structures essential for StandardTreatment outcome.
  3. Discuss the concept of compliance with the endodontic specialty standards.
Chapter Five
  1. List methods and material that cause substandard Endodontic Treatment.
  2. Describe the failure mechanism of methods and material.
  3. Discuss the role of “wait and see” practice in AP development.
  4. Cite examples of noncompliance with endodontic specialty standards.
Chapter Six
  1. Use the 4ROD protocol to investigate substandard Endodontic Treatment.
  2. Explain to the patient the 4ROD findings before, during and after performing.
  3. Provide examples of the crown, pulp chamber, and canal findings.
Chapter Seven
  1. Define Interim Endodontic Therapy.
  2. Describe advantages of surgical elimination of AP Infections.
  3. Recognize the importance of native Bone regeneration for Implant Placement.

Recognition and Credits

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PennWell Corporation is an ADA CERP recognized provider.

ADA CERP is a service of the American Dental Association to assist dental professionals in identifying quality providers of continuing dental education. ADA CERP does not approve or endorse individual courses or instructors, nor does it imply acceptance of credit hours by boards of dentistry.

Continuing education credits awarded for participating in the CE activity may or may not apply toward license renewal or specific license requirements in all states. It is the responsibility of each participant to verify the requirements of his/her state licensing board(s).

PennWell designates this activity for 4.5 credit hours of continuing education credits.

Concerns or complaints about a CE provider may be directed to the provider or to ADA CERP at

AGD PACE LogoThe PennWell Corporation is designated as an Approved PACE Program Provider by the Academy of General Dentistry. The formal continuing dental education programs of this program provider are accepted by the AGD for Fellowship, Mastership and membership maintenance credit. Approval does not imply acceptance by a state or provincial board of dentistry or AGD endorsement. The current term of approval extends from (11/1/2015) to (12/31/2019) Provider ID# 320452.

Dental Board of California: Provider 4527, course registration number 01-4527-15160.
“This course meets the Dental Board of California’s requirements for 4.5 unit of continuing education.”

Requirements For Successful Completion

To receive credit for your participation in this webinar you will be required to complete the online program examination. To complete the online examination participants must be registered and signed-in to this website and have reviewed the program in its entirety. At the end of the program a link will be provided directing you to the program course exam. Once completed and submitted an immediate grade report will be displayed. All participants scoring at least 70% on the examination will receive a CE Verification Form verifying 4.5 CE credits. Verification forms may be viewed and printed immediately as well as accessed anytime in the future (24/7) from within the user records page of this website.

Not enough time to complete your online examination? No problem, online examinations may be completed anytime during the effective period of the program. Participants requiring more time to complete an examination may return to this website, sign-in and complete the online examination.

Disclosure Declaration

Presenter Disclosure: Dr. Abou-Rass, has no financial interest in any of the products or manufacturers mentioned

Commercial Support: This course was developed without commercial support.

Provider Disclosure: PennWell does not have a leadership position or a commercial interest in any products or services discussed or shared in this educational activity, No manufacturer or third party has had any input into the development of course content.

CE Planner Disclosure: Heather Hodges, CE Coordinator does not have a leadership or commercial interest with any commercial supporter, or with products or services discussed in this educational activity. Heather can be reached at

Image Authenticity: No images in this educational activity have been modified or altered.

Scientific Basis: All content has been derived from references listed and/or the author’s clinical experience.

Known Benefits and Limitations: Information presented in this educational activity represents best practices in evidenced based dentistry with potential benefit for the patient and clinician. No off label or experimental treatments are discussed.

Educational Disclaimer: Completing a single continuing education course does not provide enough information to result in the participant being an expert in the field related to the course topic. It is a combination of many educational courses and clinical experience that allows the participant to develop skills and expertise.

Viewing Information

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