clinical management of a mandibular first molar with supernumerary distal root radix entomolaris

Journal of Taibah University Medical Sciences (2014) 9(1), 81–84 Taibah University Journal of Taibah University Medical Sciences www.sciencedirect.com Case Report Clinical management of a mandibular first molar with supernumerary distal root (radix entomolaris) Mothanna Alrahabi, PhD Department of Restorative Dentistry, College of Dentistry, Taibah University, Medina, Kingdom of Saudi Arabia Received 14 August 2013; revised 28 October 2013; accepted November 2013 ‫ﺍﻟﻤﻠﺨﺺ‬ ‫ﻳﻌﺘﺒﺮ ﺍﻟﺠﺬﺭ ﺍﻟﺮﺣﻮﻱ ﺍﻟﺰﺍﺋﺪ ﻓﻲ ﺍﻟﺠﻬﺔ ﺍﻟﻠﺴﺎﻧﻴﺔ ﺍﻟﻘﺎﺻﻴﺔ ﺃﺣﺪ ﺍﻻﺧﺘﻼﻓﺎﺕ ﺍﻟﺘﺸﺮﻳﺤﻴﺔ ﻓﻲ‬ ‫ ﻭﻳﺤﺘﺎﺝ ﻫﺬﺍ ﺍﻻﺧﺘﻼﻑ ﺍﻟﺘﺸﺮﻳﺤﻲ ﺇﻟﻰ ﻋﻨﺎﻳﺔ ﺧﺎﺻﺔ‬،‫ﺍﻟﺮﺣﻰ ﺍﻷﻭﻟﻰ ﺑﺎﻟﻔﻚ ﺍﻟﺴﻔﻠﻲ‬ ‫ ﺗﺼﻒ ﻫﺬﻩ‬.‫ﻭﺫﻟﻚ ﻟﻠﺤﻔﺎﻅ ﻋﻠﻰ ﻣﺴﺘﻮﻯ ﻧﺠﺎﺡ ﻋﺎﻝ ﻟﻤﻌﺎﻟﺠﺔ ﺃﻧﻔﺎﻕ ﺟﺬﻭﺭ ﺍﻷﺳﻨﺎﻥ‬ ‫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 ‫ﻣﻌﺮﻓﺔ ﺗﺸﺮﻳﺢ ﺍﺍﻟﻘﻨﻮﺍﺕ ﺍﻟﺠﺬﺭﻳﺔ ﻭﺃﻫﻤﻴﺔ ﺍﻟﺘﺼﻮﻳﺮ ﺍﻟﺸﻌﺎﻋﻲ ﻗﺒﻞ ﻣﻌﺎﻟﺠﺔ ﺍﻟﺠﺬﻭﺭ‬ ‫ﺟﺮﺍﺣﻴﺎ‬ ‫ ﺍﻟﺠﺬﺭ ﺍﻟﺮﺣﻮﻱ ﺍﻟﺰﺍﺋﺪ; ﺍﻟﺮﺣﻰ; ﺍﻟﻔﻚ ﺍﻟﺴﻔﻠﻲ; ﻗﻨﺎﺓ ﺍﻟﺠﺬﺭ; ﻋﻠﻢ ﺍﻟﺘﺸﺮﻳﺢ‬:‫ﺍﻟﻜﻠﻤﺎﺕ ﺍﻟﻤﻔﺘﺎﺡ‬ Abstract Radix entomolares, a supernumerary root on a mandibular molar, located distolingually, is an anatomical variation of the mandibular first molar This variation requires special care in order to maintain a high success rate of root canal treatment This paper describes the procedure for treatment of a mandibular first molar with three roots (one mesial and two distal) and four canals (two mesial and one in each distobuccal and distolingual root) This case report reveals the importance of anatomical knowledge of root canals and preoperative radiographs Keywords: Anatomy; Mandibular; Molar; Radix entomolares; Root canal Ó 2014 Taibah University Production and hosting by Elsevier Ltd All rights reserved Introduction Thorough knowledge of root canal anatomy, both normal and abnormal, is essential for successful root canal treatment.1 The 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 usually straight with a wide oval canal or two round canals.2 Sometimes, however, the morphology and number of roots of the mandibular first molar vary; the major variant is the presence of supernumerary roots distolingually This variant, mentioned for the first time by Carabelli,3 is known as radix entomolaris.4 The prevalence of supernumerary roots is less than 3% in African populations, 4.2% in whites, less than 5% in Eurasian 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: mrahabi@taibahu.edu.sa (M Alrahabi) Peer review under responsibility of Taibah University Production and hosting by Elsevier 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 cervical 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-separate 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 tooth for a few days The pain kept him awake at night and was radiating up the side of his 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 noncontributory 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 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 locate the other distal canal, on the lingual side The root canals were explored with a precurved K-file ISO number 15 (Dentsply Maillefer) The working length was determined electronically with an apex locator (Root ZXII JMorita, Suita City, Osaka, Japan) and confirmed by periapical radiography (Figure 4) Figure 2: Diagnostic X-ray Figure 3: Diagnostic X-ray with horizontal angulation The root canals were shaped with ProTaper rotary instruments (Dentsply Maillefer) During preparation, Glyde (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 gutta-percha master cone was confirmed radiographically (Figure 5) Then, the canals were obturated (Figure 6) by vertical compaction 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 referred to an operative clinic for permanent restoration Discussion Figure 4: Working length confirmation by periapical radiography Figure 5: Master cone confirmation by periapical radiography There have been several reports of the occurrence of supernumerary roots (an extra distolingual root) in permanent mandibular molars The anatomical variant radix entomolaris 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 access 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 working length It is preferable to use nickel–titanium rotary instruments and copious irrigation to improve cleaning and shaping the root canal system.13 Prior treatment should be strict to avoid procedural accidents Conclusion In conclusion, to ensure successful root canal treatment, three factors should be considered: thorough knowledge of root canal anatomy and treatment procedures, accurate diagnosis and good skill Conflict of interest We have no conflict of interest to declare References Figure 6: Final root obturation X-ray canals were disinfected with NaOCl solution (2.5%) The canals were prepared with an F1 instrument and then dried and filled with CaOH2 paste (Metapast, Meta Biomed Co., Seoul, Republic of Korea) The access was closed with a cotton pellet and temporary restoration Two weeks later, the patient returned for completion of endodontic therapy Local anaesthesia was again administered, Segura-Egea JJ, Jimenez-Pinzon A, Rios-Santos JV Endodontic therapy in a 3-rooted mandibular first molar: importance of a thorough radiographic examination J Can Dent Assoc 2002; 9: 541–544 Skidmore AE, Bjorndal AM Root canal morphology of the human mandibular first molar Oral Surg Oral Med Oral Pathol 1971; 5: 778–784 Carabelli G Systematisches Handbuch der Zahnheilkunde 2nd ed Vienna: Braumuller and Seidel; 1844, p 114 Bolk L Bemerkuăngen uăber Wurzelvariationen am menschlichen unteren Molaren Zeit Morphol Anthropol 1915; 17: 605–610 De Moor RJ, Deroose CA, Calberon FL The radix entomolaris in mandibular first molars: an endodontic challenge Int Endod J 2004; 37: 789–799 Carlsen O, Alexandersen V Radix entomolaris: identification and morphology Scand J Dent Res 1990; 5: 363–373 84 M Alrahabi Curzon ME, Curzon JA Three-rooted mandibular molars in the Keewatin Eskimo J Can Dent Assoc (Tor) 1971; 2: 71–72 Walker RT Root form and canal anatomy of mandibular second molars in a southern Chinese population J Endod 1988; 7: 325–329 Walker RT, Quackenbush LE Three-rooted lower first permanent molars in Hong Kong Chinese Br Dent J 1985; 9: 298–299 10 Klein RM, Blake SA, Nattress BR, Hirschmann PN Evaluation of X-ray beam angulation for successful twin canal identification in mandibular incisors Int Endod J 1997; 1: 58–63 11 Ingle JI, Heithersay GS, Hartwell GR, Goerig AC, Marshall FJ, Krasny RM Endodontics 5th ed Hamilton, Ontario: BC Decker Inc.; 2002 p 218–258 12 Krasner P, Rankow HJ Anatomy of the pulp-chamber floor J Endod 2004; 1: 5–16 13 Calberson FL, De Moor RJ, Deroose CA The radix entomolaris and paramolaris: clinical approach in endodontics J Endod 2007; 1: 58–63