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provided by Elsevier - Publisher Connector Journal of Taibah University Medical Sciences (2014) 9(1), 81–84

Taibah University Journal of Taibah University Medical Sciences

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Case Report

Clinical management of amandibular first with supernumerary distal root (radix entomolaris)

Mothanna Alrahabi, PhD

Department of Restorative , College of Dentistry, Taibah University, Medina, Kingdom of Saudi Arabia

Received 14 August 2013; revised 28 October 2013; accepted 1 November 2013

ﺍﻟﻤﻠﺨﺺ Keywords: Anatomy; Mandibular; Molar; Radix entomolares; Root canal ﻳﻌﺘﺒﺮ ﺍﻟﺠﺬﺭ ﺍﻟﺮﺣﻮﻱ ﺍﻟﺰﺍﺋﺪ ﻓﻲ ﺍﻟﺠﻬﺔ ﺍﻟﻠﺴﺎﻧﻴﺔ ﺍﻟﻘﺎﺻﻴﺔ ﺃﺣﺪ ﺍﻻﺧﺘﻼﻓﺎﺕ ﺍﻟﺘﺸﺮﻳﺤﻴﺔ ﻓﻲ ﺍﻟﺮﺣﻰ ﺍﻷﻭﻟﻰ ﺑﺎﻟﻔﻚ ﺍﻟﺴﻔﻠﻲ، ﻭﻳﺤﺘﺎﺝ ﻫﺬﺍ ﺍﻻﺧﺘﻼﻑ ﺍﻟﺘﺸﺮﻳﺤﻲ ﺇﻟﻰ ﻋﻨﺎﻳﺔ ﺧﺎﺻﺔ Ó 2014 Taibah University. Production and hosting by Elsevier ﻭﺫﻟﻚ ﻟﻠﺤﻔﺎﻅ ﻋﻠﻰ ﻣﺴﺘﻮﻯ ﻧﺠﺎﺡ ﻋﺎﻝ ﻟﻤﻌﺎﻟﺠﺔ ﺃﻧﻔﺎﻕ ﺟﺬﻭﺭ ﺍﻷﺳﻨﺎﻥ. ﺗﺼﻒ ﻫﺬﻩ .Ltd. All rights reserved ﺍﻟﻤﻘﺎﻟﺔ ﺍﻹﺟﺮﺍﺀﺍﺕ ﺍﻟﻌﻼﺟﻴﺔ ﻟﻠﺮﺣﻰ ﺍﻷﻭﻟﻰ ﺑﺎﻟﻔﻚ ﺍﻟﺴﻔﻠﻲ ﺑﺜﻼﺛﺔ ﺟﺬﻭﺭ (ﺟﺬﺭ ﺇﻧﺴﻲ ﻭﺟﺬﺭﺍﻥ ﻗﺎﺻﻴﺎﻥ) ﻭﺃﺭﺑﻌﺔ ﻗﻨﻮﺍﺕ (ﻗﻨﺎﺗﺎﻥ ﻓﻲ ﺍﻟﺠﺬﺭ ﺍﻹﻧﺴﻲ ﻭﻗﻨﺎﺓ ﻓﻲ ﺍﻟﺠﺬﺭ ﺍﻟﻠﺴﺎﻧﻲ ﺍﻟﻘﺎﺻﻲ ﻭﻗﻨﺎﺓ ﻓﻲ ﺍﻟﺠﺬﺭ ﺍﻟﺸﺪﻗﻲ ﺍﻟﻘﺎﺻﻲ) ﻳﻈﻬﺮ ﺗﻘﺮﻳﺮ ﻫﺬﻩ ﺍﻟﺤﺎﻟﺔ ﺃﻫﻤﻴﺔ Introduction ﻣﻌﺮﻓﺔ ﺗﺸﺮﻳﺢ ﺍﺍﻟﻘﻨﻮﺍﺕ ﺍﻟﺠﺬﺭﻳﺔ ﻭﺃﻫﻤﻴﺔ ﺍﻟﺘﺼﻮﻳﺮ ﺍﻟﺸﻌﺎﻋﻲ ﻗﺒﻞ ﻣﻌﺎﻟﺠﺔ ﺍﻟﺠﺬﻭﺭ ﺟﺮﺍﺣﻴﺎ. Thorough knowledge of root canal anatomy, both normal and ﺍﻟﻜﻠﻤﺎﺕ ﺍﻟﻤﻔﺘﺎﺡ: ﺍﻟﺠﺬﺭ ﺍﻟﺮﺣﻮﻱ ﺍﻟﺰﺍﺋﺪ; ﺍﻟﺮﺣﻰ; ﺍﻟﻔﻚ ﺍﻟﺴﻔﻠﻲ; ﻗﻨﺎﺓ ﺍﻟﺠﺬﺭ; ﻋﻠﻢ ﺍﻟﺘﺸﺮﻳﺢ abnormal, is essential for successful .1 The Abstract mandibular first molar typically has two well-defined roots: a mesial root characterised by a flattened mesiodistal surface and widened buccolingual surface, and a distal root, which is Radix entomolares, a supernumerary root on a mandibular 2 molar, located distolingually, is an anatomical variation of usually straight with a wide oval canal or two round canals. the mandibular first molar. This variation requires special Sometimes, however, the morphology and number of roots care in order to maintain a high success rate of root canal of the mandibular first molar vary; the major variant is the treatment. This paper describes the procedure for treatment presence of supernumerary roots distolingually. This variant, mentioned for the first time by Carabelli,3 is known as radix of a mandibular first molar with three roots (one mesial and 4 two distal) and four canals (two mesial and one in each dis- entomolaris. tobuccal and distolingual root). This case report reveals the The prevalence of supernumerary roots is less than 3% in importance of anatomical knowledge of root canals and African populations, 4.2% in whites, less than 5% in Eurasian preoperative radiographs. and Asian populations and greater than 5% in populations

Corresponding address: Department of Operative Dentistry & Endodontic, College of Dentistry, Taibah University, Medina, Kingdom of Saudi Arabia. Tel.: +966 597674522. E-mail: [email protected] (M. Alrahabi) Peer review under responsibility of Taibah University.

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1658-3612 Ó 2014 Taibah University. Production and hosting by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.jtumed.2013.11.001 82 M. Alrahabi with Mongolian traits.5 Radix entomolaris was classified by Carlsen and Alexandersen6 according to the location of its cer- vical part, resulting in four types. A and B refer to a distally located cervical part of the radix entomolaris with two normal and one normal distal root components, respectively; C refers to a mesially located cervical part, while AC refers to a central location between the distal and mesial root components. This classification allows identification of separate and non-sepa- rate radix entomolaris. This report describes endodontic therapy on a three-rooted mandibular first molar.

Case report

A 22-year-old Syrian male patient presented to the clinic of the dental school at Taibah University with a history of severe pain in the lower-right posterior for a few days. The pain kept him awake at night and was radiating up the side of his Figure 2: Diagnostic X-ray. face. Clinical examination revealed bad amalgam restoration on tooth no. 30 with recurrent caries on the mesial (Figure 1). The tooth was very sensitive to percussion and was nonresponsive to Endo Ice (Hygienic Corp., Akron, Ohio, USA). The medical history of the patient was non- contributory. A diagnosis of necrotic pulp with acute apical periodontitis was performed. Emergency treatment involved access cavity preparation, irrigation with NaOCl and placement of a dry cotton pellet for temporization. The patient was then referred to an endodontic specialty clinic. Diagnostic X-rays were taken from various horizontal angles (Figures 2 and 3), which showed an additional distal root. Local anaesthesia was administered, and the tooth was isolated by a rubber dam. Access was prepared with an endo access bur no. E0123 and Endo Z (Dentsply Maillefer, Ballaigues, Switzerland). As the first distal canal was buccal, access was modified to lo- cate the other distal canal, on the lingual side. The root canals Figure 3: Diagnostic X-ray with horizontal angulation. were explored with a precurved K-file ISO number 15 (Dents- ply Maillefer). The working length was determined electroni- cally with an apex locator (Root ZXII. JMorita, Suita City, The root canals were shaped with ProTaper rotary instru- Osaka, Japan) and confirmed by periapical radiography ments (Dentsply Maillefer). During preparation, Glyde (Figure 4). (Dentsply Maillefer) was used as the lubricant, and the root

Figure 1: OPG X-ray reveal recurrent caries under amalgam restoration on tooth No.30. Clinical management 83

and the tooth was isolated under a rubber dam. The CaOH2 paste was removed by irrigation, and the canals were shaped with F2 and F3 instruments. The canals were dried, and a gut- ta-percha master cone was confirmed radiographically (Figure 5). Then, the canals were obturated (Figure 6) by vertical com- paction with an Obtura III device and AH26 Sealer (Dentsply Maillefer), and the access was closed with glass ionomer cement (Ketac Fil, 3M ESPE, Seefeld, Germany). The patient was re- ferred to an operative clinic for permanent restoration.

Discussion

There have been several reports of the occurrence of supernu- merary roots (an extra distolingual root) in permanent man- dibular molars. The anatomical variant radix entomolaris Figure 4: Working length confirmation by periapical radiography. has been considered by some authors to be a genetic trait rather than a developmental anomaly.7,8 Radix entomolaris is commonly found distolingually. It may be a short conical extension or a full-length root. In this case, the supernumerary root was distolingual, full length and contained pulpal tissue. A third root can be detected radiographically in 90% of cases,9 but sometimes additional X-rays from different horizontal angles are required.10,11 In a distolingually located orifice of a radix entomolaris, the access cavity should be modified to establish straight-line ac- cess. Following orifice location will help in conserving the tooth structure,12 and using an electronic apex locater with X-ray to determine the increases in the accuracy of the work- ing length. It is preferable to use nickel–titanium rotary instru- ments and copious irrigation to improve cleaning and shaping the root canal system.13 Prior treatment should be strict to avoid procedural accidents.

Conclusion Figure 5: Master cone confirmation by periapical radiography.

In conclusion, to ensure successful root canal treatment, three factors should be considered: thorough knowledge of root ca- nal anatomy and treatment procedures, accurate diagnosis and good skill.

Conflict of interest

We have no conflict of interest to declare.

References

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