Restor Dent Endod.  2014 May;39(2):132-136.

Endodontic management of a mandibular second molar with radix entomolaris: a case report

• Hannah R
• Kandaswamy D
• Jayaprakash N

Abstract

The presence of radix entomolaris (RE) in a mandibular first molar is a common occurrence in certain ethnic groups, but the presence of RE in a mandibular second molar is a rare occurrence. In the present case, RE was identified from preoperative radiographs and confirmed using cone-beam computed tomography (CBCT). The access cavity was modified to locate the RE. Cleaning and shaping were performed with nickel-titanium rotary instruments. Obturation was completed with gutta-percha cones using AH Plus (Dentsply Detrey GmbH) as sealer. From the CBCT axial images, the RE was determined to have a Type III curvature by the De Moor classification, Type B separate RE by the Carlsen and Alexandersen classification, and radiographically, a Type i image by the Wang classification. The presence of RE in the mandibular second molar makes it essential to anticipate and treat the distolingual root canal. This case report highlights the usefulness of CBCT for assessing RE in the mandibular second molar, which can help the clinician in making a confirmatory diagnosis and assessing the morphology of the root canal.

Keyword

Cone-beam computed tomography; Radix entomolaris; Second molar

MeSH Terms

Classification
Cone-Beam Computed Tomography
Dental Pulp Cavity
Diagnosis
Ethnic Groups
Gutta-Percha
Humans
Molar*
Gutta-Percha

Figure

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  Figure 1 (a) Preoperative radiograph of #37; (b) Access opening showing the presence of RE, MB, ML, and DB canal orifices; (c) Working length radiograph; (d) Postoperative radiograph. RE, radix entomolaris; MB, mesio buccal; ML, mesio lingual; DB, disto buccal.

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  Figure 2 CBCT images of #37 confirming the presence of a separate RE (arrow) (a) At the cervical level; (b) At the apical level. (c) The CBCT enlarged section at cervical level. (d) CBCT sagittal section showing type III curvature.

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