Interradicular Root Canals in Mandibular First Molars: A Literature Review and Ex Vivo Study

Thomas Gerhard Wolf; Stefan Wentaschek; Richard J Wierichs; Benjamín Briseño-Marroquín

doi:10.1016/j.joen.2018.10.019

Interradicular Root Canals in Mandibular First Molars: A Literature Review and Ex Vivo Study

J Endod. 2019 Feb;45(2):129-135. doi: 10.1016/j.joen.2018.10.019.

Authors

Thomas Gerhard Wolf¹, Stefan Wentaschek², Richard J Wierichs³, Benjamín Briseño-Marroquín⁴

Affiliations

¹ Department of Restorative, Preventive and Pediatric Dentistry, School of Dental Medicine, University of Bern, Bern, Switzerland; Department of Operative Dentistry, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany.
² Department of Prosthetic Dentistry, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany.
³ Department of Operative Dentistry, Periodontology and Preventive Dentistry, Rheinisch-Westfälische Technische Hochschule Aachen University, Aachen, Germany; Department of Biohybrid and Medical Textiles, Institute of Applied Medical Engineering, Helmholtz Institute, Rheinisch-Westfälische Technische Hochschule Aachen University, Aachen, Germany.
⁴ Department of Restorative, Preventive and Pediatric Dentistry, School of Dental Medicine, University of Bern, Bern, Switzerland; Department of Operative Dentistry, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany. Electronic address: benjamin.briseno@zmk.unibe.ch.

PMID: 30711167
DOI: 10.1016/j.joen.2018.10.019

Abstract

Introduction: Successful endodontic treatment vastly depends to a high degree on an accurate knowledge of root canal system morphology. It is a prerequisite to be aware of all possible reservoirs where bacteria and/or toxins can persist, compromising the surrounding tissues; such knowledge results in endodontic success.

Methods: The presence of interradicular canals and diverticula between the pulp chamber floor and the bifurcation area surface of 117 mandibular first molars was investigated. Access cavities were prepared, the teeth were embedded in plastic, and the pulp chambers were flooded with methylene blue and then centrifuged. An average of 4.2 (0.145 ± 0.03 mm thickness) slices per tooth were obtained by means of a diamond band saw. The presence of interradicular canals and diverticula was investigated using a light microscope (125×).

Results: Interradicular canals were observed in 9 teeth. Seven teeth had 1 interradicular canal, and 2 teeth had 2 interradicular canals. Diverticula (blind interradicular canals) were observed in 11 teeth originating either on the pulp chamber floor or the bifurcation side. The number of diverticula per tooth varied between 1 and 5 and originated in 3 teeth in the pulp chamber floor and 8 teeth in the bifurcation area. Two teeth had both 1 interradicular canal and 3 diverticula. Of the 117 mandibular molars investigated, 18 had either 1 or 2 interradicular canals, 1 to 5 diverticula, or an interradicular canal and 3 diverticula.

Conclusions: Based on the results obtained with this ex vivo study and because of the difficulties involved in the clinical performance of mechanical cleaning of possibly existing interradicular canals, it is highly recommended to perform thorough chemical cleaning and disinfection of the pulp chamber floor area in order to enhance the sealing possibility of such structures and minimize treatment failure.

Keywords: Diverticula; internal morphology; interradicular canal; mandibular first molars.

Publication types

Review

MeSH terms

Dental Pulp Cavity / anatomy & histology*
Dental Pulp Cavity / pathology
Dental Pulp Cavity / ultrastructure
Humans
Mandible*
Microscopy
Molar / anatomy & histology*
Root Canal Therapy / methods