Webinars > Treatment Resistant Lesions

Treatment Resistant Lesions

Saturday, November 21, 2015 | Time: 11:00 AM - 1:00 PM PST

CDE Credits: 2.00 Teaching Methods: Lecture; Live Online or Self-Instructional Video Length: 2 hours

PDL is an ADA CERP recognized provider. PDL designates this activity for 2.00 hours continuing dental education credit.

Webinar Title: Treatment Resistant Lesions

Presenter: Dr. Frederick Barnett

Date Recorded: November 21, 2015

Duration: 2 hours

CDE Credits: 2.00 CDE credits will be issued by Pure Dental Learning



Pulp and periapical diseases are initiated primarily by microbial factors. Healing, therefore, occurs when the infection is properly controlled and the host-parasite relationship is made favorable for the host. This lecture will outline the etiology and clinical features of refractory endodontic disease. Extra-radicular endodontic infections (microbial and virus), 'sulfa-granules' and periapical biofilm will also be reviewed.

Course Outline

  1. Clinical and radiographic features of post-treatment endodontic disease.
  2. The role of intraradicular and extraradicular root surface biofilm in treatment failures.
  3. The role of extraradicular infections (ie: sulfa granules, etc.)


  1. Describe the etiological factors responsible for treatment-resistant PA disease.
  2. Understand the role of microorganisms/biofilm in post-treatment endodontic disease.
  3. Understand the significance of extra-radicular infection, periapical "sulfa-granules" and periapical plaque.

Course Evaluation

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Resources and References

See Below

Supplementary Material

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Dr. Frederick Barnett has no relevant commercial relationships.

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Dr. Frederick Barnett

Dr. Frederick Barnett


131 Fairview Road
Penn Valley, PA 19072, USA


Dr. Barnett received his DMD degree in 1978 and his Certificate in Endodontics in 1981, both from the University of Pennsylvania, School of Dental Medicine. He received his Board Certification in Endodontics in 1988, has served as the Director of Postdoctoral Endodontics at the University of Pennsylvania, and is currently the Chairman of the Department of Dental Medicine and Chairman and Program Director of the IB Bender Postdoctoral Endodontic Program at Albert Einstein Medical Center in Philadelphia. Dr. Barnett has written numerous scientific and clinical papers and has lectured nationally and internationally on the Treatment of Endodontic Infections, Revascularization, Dental Trauma and Contemporary Endodontic Treatment. He currently serves on the Advisory Board of the Dental Traumatology Journal, is a Director of the International Association of Dental Traumatology and is an Associate Editor of the Journal of Endodontics. Dr. Barnett has also been in private practice in Endodontics from 1981-2011.

Resources and References

  1. Tronstad L, Barnett F, Riso K, Slots J. Extra-radicular endodontic infections. Endod Dent Traumatol 1987; 3: 86-90.
  2. Tronstad L, Barnett F, Cervone F. Periapical bacterial plaque in teeth refractory to endodontic treatment. Endod Dent Traumatol 1990; 6: 73-77.
  3. Sunde PT, Olsen I, Debelian GJ, Tronstad L. Micro biota of periapical lesions refractory to endodontic therapy. J Endod. 2002 Apr;28(4}:304-10.
  4. Sunde PT, Olsen I, Gobel UB, Theegarten D, Winter S, Debelian GJ, Tronstad L, Moter A. Fluorescence in situ hybridization (FISH) for direct visualization of bacteria in periapical lesions of asymptomatic root-filled teeth. Microbiology. 2003 May;l49(Pt 5):1095-102.


Original Release Date: November 21, 2015
Review Date: TBD
*Expiration Date: November 21, 2018

CDE Credits

PDL 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.

Concerns or complaints about a CDE provider may be directed to the provider or to ADA CERP at cerp@ada.org

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