Restor Dent Endod.  2020 Feb;45(1):e1. 10.5395/rde.2020.45.e1.

The prevalence of radix molaris in the mandibular first molars of a Saudi subpopulation based on cone-beam computed tomography

• AL-Alawi H
• Al-Nazhan
• Al-Maflehi N
• Aldosimani MA
• Zahid MN
• Shihabi GN

• KMID: 2470337
• DOI: http://doi.org/10.5395/rde.2020.45.e1

Abstract

OBJECTIVES
The purpose of this study was to determine the incidence of radix molaris (RM) (entomolaris and paramolaris) in the mandibular first permanent molars of a sample Saudi Arabian subpopulation using cone-beam computed tomography (CBCT).
MATERIALS AND METHODS
A total of 884 CBCT images of 427 male and 457 female Saudi citizens (age 16 to 70 years) were collected from the radiology department archives of 4 dental centers. A total of 450 CBCT images of 741 mature mandibular first molars that met the inclusion criteria were reviewed. The images were viewed at high resolution by 3 examiners and were analyzed with Planmeca Romexis software (version 5.2).
RESULTS
Thirty-three (4.5%) mandibular first permanent molars had RM, mostly on the distal side. The incidence of radix entomolaris (EM) was 4.3%, while that of radix paramolaris was 0.3%. The RM roots had one canal and occurred more unilaterally. No significant difference in root configuration was found between males and females (p > 0.05). Types I and III EM root canal configurations were most common, while type B was the only RP configuration observed.
CONCLUSIONS
The incidence of RM in the mandibular first molars of this Saudi subpopulation was 4.5%. Identification of the supernumerary root can avoid missing the canal associated with the root during root canal treatment.

Keyword

Cone-beam CT; Mandibular first molar; Radix entomolaris; Radix molaris; Root canal morphology

MeSH Terms

Cone-Beam Computed Tomography*
Dental Pulp Cavity
Female
Humans
Incidence
Male
Molar*
Prevalence*

Figure

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  Figure 1. (A) Cone-beam computed tomography (CBCT) images of mandibular first molar showing 4 canals (arrow). (B) CBCT showing disto-buccal root with one canal (arrow). (C) Separated distal roots with one canal each (arrow).

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  Figure 2. (A) Cone-beam computed tomography (CBCT) images of mandibular first molar showing disto-lingual root bilateral entomolaris (arrow). (B) Bilateral separated roots with one canal (arrow).

Reference

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