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Year : 2021  |  Volume : 11  |  Issue : 3  |  Page : 418-422

Endodontic treatment of a hypertaurodont mandibular second molar with C-shaped canal: A case report

Department of Conservative Dentistry and Endodontics, Dr. Z.A. Dental College, AMU, Aligarh, Uttar Pradesh, India

Date of Submission29-Jun-2020
Date of Decision26-Jul-2020
Date of Acceptance05-Oct-2020
Date of Web Publication3-Sep-2021

Correspondence Address:
Dr. Shaikh Shahbaz
Department of Conservative Dentistry and Endodontics, Dr. Z.A. Dental College, AMU, Aligarh, Uttar Pradesh
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/sej.sej_168_20

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Taurodontism is a variation in tooth anatomy characterized by an enlarged pulp chamber with hypertaurodont being its most severe presentation. The complexity of endodontic treatment of hypertaurodont tooth may be compounded by coexistent C-shaped canal anatomy. A 26-year-old patient reported with spontaneous and lingering pain due to a deep carious lesion in the right mandibular second molar. Clinical and radiographic examinations were done. A diagnosis of symptomatic irreversible pulpitis with symptomatic apical periodontitis in a hypertaurodont with an associated C-shaped canal configuration was made. The cone-beam computed tomography image guide together with microscopic magnification was utilized to negotiate, clean, and shape the root canal system. The isthmus of the C-shaped canal was prepared with ultrasonic tips, while Endoactivator sonic irrigant activation was employed for effectively disinfecting of the uninstrumentable intercommunications, apical splits, and ramifications. The apical root canals were obturated by lateral condensation technique, while warm vertical compaction of gutta-percha was utilized to fill the remaining pulp chamber. A 1 year follow-up of the case reveals a functional tooth with no signs of periapical infection, indicating a successful treatment outcome.

Keywords: Cone-beam computed tomography, C-shaped canal, endodontic treatment, hypertaurodont, taurodontism

How to cite this article:
Shahbaz S, Alam S, Mishra SK, Andrabi SM. Endodontic treatment of a hypertaurodont mandibular second molar with C-shaped canal: A case report. Saudi Endod J 2021;11:418-22

How to cite this URL:
Shahbaz S, Alam S, Mishra SK, Andrabi SM. Endodontic treatment of a hypertaurodont mandibular second molar with C-shaped canal: A case report. Saudi Endod J [serial online] 2021 [cited 2021 Dec 4];11:418-22. Available from: https://www.saudiendodj.com/text.asp?2021/11/3/418/325392

  Introduction Top

Taurodontism is an aberrant tooth morphology characterized by an enlarged pulp chamber, lack of constriction at cementoenamel junction, apical displacement of the pulpal floor, and presence of bifurcations and trifurcations of the root, which could be just a few millimeters coronal to the root apex.[1] The prevalence of taurodontism ranges from 0.90% to 60% based on the ethnicity and geographic location of the reported population.[2] The occurrence of taurodont in Saudi dental patients by Ruprecht et al. and Ghaznawi was reported to be 11.3% and 8.61%, respectively.[3],[4] Most studies have found equal distribution of taurodont males and females.[3],[5]

Etiology pertaining to Taurodontism is still unclear; however, most studies suggest the cause to be the failure of the diaphragm of Hertwig's epithelial root sheath invagination at the correct horizontal level and time.[6] It usually occurs as an isolated trait in healthy patients.[7],[8] However, it is also known to be associated with genetic or developmental disorders such as Down syndrome, tricho-dento-osseous syndrome, Klinefelter syndrome, Mohr syndrome, osteoporosis, ectodermal dysplasia, thalassemia major, and cleft lip and palate.[9]

Based on the severity of taurodont it has been categorized as hypotaurodont, mesotaurodont and hypertaurodont.[9] Hypotaurodontism is the moderate enlargement of the pulp chamber at the expense of the roots, in mesotaurodontism the pulp chamber extends further down, and the tooth root divides apically than in hypotaurodont, while in hypertaurodontism the pulp chamber nearly reaches the apex with the bifurcation and trifurcation occurring near the root apices.[10]

Endodontic treatment of hypertaurodont tooth can be potentially challenging. The deep chamber increases the difficulty in locating and negotiating the root canal orifices. The instrumentation and obturation of the root canal system harbored in a short root are also challenging.[1] The associated variations in internal anatomy may include multiple roots and canals, while a few case reports have also reported coexisting C-shaped canal anatomy.

The aim of this paper is to report the endodontic management of a hypertaurodont with C-shaped canal morphology in mandibular right second mandibular molar in a nonsyndromic healthy young patient.

  Case Report Top

A 26-year-old male patient reported to the Endodontic department, with the chief complaint of pain in the lower right mandibular region. The patient gave a history of increased sensitivity to both hot and cold stimuli and occurrence of lingering spontaneous pain for a week, which had increased in intensity and frequency during the past 2 days. Medical, dental, and family history was not significant.

Intraoral examination revealed dental caries on the right mandibular first (#46) and second molar (#47). The exaggerated hyperalgesic response to the electric and cold pulp test was replicated on tooth #47, which was tender to percussion. Radiographic examination revealed deep dental caries approaching the dental pulp horn on #46 and #47. Tooth #47 had an oversized pulp chamber with short roots consistent with the features of hypertaurodontism [Figure 1]a. A diagnosis of symptomatic irreversible pulpitis with symptomatic apical periodontitis was made in #47, and endodontic intervention was planned. Tooth #46 elicited a normal pulp reponse to pulp sentivity tests and it was decided to treat #46 by complete excavation of caries followed by restoration with direct composite.
Figure 1: Preoperative Intraoral periapical radiograph of the hypertaurodontic mandibular right second molar (a). Endodontic files placed at the working length of mesial and distal root canals (b)

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Following the informed consent of the patient, the tooth #47 was anesthetized using 1.8 ml of 2% lidocaine containing 1:80,000 epinephrine, and the endodontic treatment was initiated under rubber dam isolation. A dental operating microscope (G6, Global Surgical Corp, St. Louis, MO, USA) was used throughout the procedure. The access cavity was prepared with endo access bur (bur type FG-1; Dentsply Sirona, UK) and refined with endo Z bur (Dentsply Maillefer, Ballaigues, Switzerland). The pulp tissue was removed from the pulp chamber with sharp curettes and an ethylenediaminetetraacetic acid (EDTA), and carbamide peroxide gel (Glyde file prep, Dentsply Maillefer, Ballaigues, Switzerland) was placed in the chamber to eliminate the remnant pulp. The chamber was flushed with solution of 5% sodium hypochlorite solution (NaOCl) (Prime Dental, India), and it was also occasionally left in the pulp chamber for a few minutes to allow it to act on the vital pulp tissue. Intracanal heating of 5% NaOCl was also intermittently done by placing a tip of System B (Analytic Endodontics, Orange, CA, USA) set at 180°C by activating it for 10 s on and off. This sequence was repeated until the pulp tissue was completely eliminated from the pulp chamber. After pulp extirpation from the pulp chamber, glide path was created with 10, 15, and 20 K-Files (MICRO-MEGA, France), during which the remaining radicular pulp was removed. The root canals were lubricated with EDTA and carbamide peroxide gel (Glyde file prep) and flushed with normal saline until the glide path was achieved till 20 K-File.

Working length was determined with an apex locator (Root ZX, Morita, Tokyo, Japan) and confirmed radiographically [Figure 1]b. While scouting for root canal orifices, the file encountered catch points along the two root canal orifices which had been identified. Due to the deep pulp chamber and confounding catch points along the identified orifices, it was difficult to ascertain the definite anatomy of the pulp chamber and the root canal system. A cone-beam computed tomography (CBCT) scan was therefore planned to accurately delineate the internal anatomy of tooth #47. It revealed a continuous C-shaped configuration at the bifurcation zone [Figure 2]a, [Figure 2]b, [Figure 2]c. The initial preparation was done with hand K-Files till 20 K file. The C-shaped canal was prepared along the length of the isthmus with the ultrasonic tips (ED18 and ED18D, Helse Ultrasonic, Ocoee, Florida). The subsequent filing was done with Protaper gold file system up to F2 (Dentsply Maillefer, Ballaigues, Switzerland). 5% NaOCl was alternated with Smear Clear (Sybron Endo, Orange, CA) (17% EDTA cetrimide and surfactants) as an irrigating solution. EndoActivator (Dentsply Tulsa Dental Specialties, Tulsa, OK) sonic irrigant activation was used to assist in cleaning. Calcium hydroxide (RC Cal, Prime Dental Products) was placed for 1 week as intracanal medicament. In the subsequent visit, calcium hydroxide was removed completely by copiously flushing, replenishing, and activating 5% NaOCl with Endoactivator. The canals were then subjected to final disinfection protocol by irrigating with 5% NaOCl and Smear Clear (17%EDTA cetrimide and surfactants), dried with paper points (Meta Biomed Co., Chungcheongbuk, Korea) and obturated using a modified obturation technique as described by Tsesis et al.[11] The obturation protocol included coating the walls with AH Plus sealer (Dentsply Sirona) and then combining lateral condensation of the gutta-percha in the apical root canal with vertical compaction of gutta-percha in the remaining pulp chamber using System B. Posterior composite restoration was done as a final restoration. Follow-up visit was conducted after 1 year [Figure 3].
Figure 2: Preoperative cone beam computed tomographic image. Axial section at the level occlusal to the bifurcation (a), at the level of bifurcation reveals continuous C-shaped canal morphology (b) and at the level slightly apical to the bifurcation reveals C-shaped canal morphology being broken by dentin infiltration into a semi colon configuration with a larger mesial canal and smaller distal canal (c)

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Figure 3: Postoperative radiograph

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  Discussion Top

While taurodont teeth might occasionally be encountered in patients associated with certain disorder or syndrome, it is often present in a healthy patient.[12] In the present case, the taurodont tooth were present in a healthy adult with no associated disorder. The Taurodontic index (TI) of #47 was calculated from the periapical radiograph based on the method proposed by Shifman and Chanannel.[8] A tooth is categorized as a hypertaurodont when the TI lies between 40% and 75%. The TI of #47 was 74.2%, and it was therefore categorized as a hypertaurodont [Figure 4]. The calculation from the CBCT images would have yielded a more accurate TI.[9],[13] However, it was not utilized in the present case as the CBCT images were obtained after the access opening to the pulp chamber had been done.
Figure 4: Calculation of the Taurodont Index = V1/V2 × 100 with V1 = Height of pulp chamber and V2 = Distance between roof of pulp chamber and root apex V1 = 14.1 mm, V2 = 19 mm, Taurodont Index = 14.1/19 × 100 = 74.2

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CBCT scan was decided as during the scouting of the root canals by hand files, catch points were encountered between the two negotiated root canal orifices. The CBCT scan images allow an accurate understanding of the internal anatomy and offer a considerable guide to clinicians in negotiating complex anatomy. In the present case report, CBCT images revealed the presence of a C-shaped canal configuration, which was the cause of encountering partially negotiable catch points between the two canal orifices. The canal configuration was visualized on CBCT scans as a continuous uninterrupted C-shaped canal and could be classified as C1 type based on Fans classification.[14] Apically, the canals split into a semicolon-shaped configuration with a larger mesial and a smaller distal canal.

The scientific literature has reported variability in the prevalence of hypertaurodont in different ethnic and geographic groups.[13],[15],[16] The prevalence data have relied on the interpretation of two-dimensional radiographic images, and the internal three dimensional anatomy of hypertaurodont in a population-based study has not been reported. C-shaped canal anatomy coexisting in a hypertaurodont tooth can be an occurrence which has not been adequately studied and reported. There is a lack of data with three dimensional analysis of the internal anatomy of hypertaurodont teeth, and only a few case reports have identified the coexistence of C-shaped canal with hypertaurodont teeth. Radwan and Kim reported taurodont teeth associated with C-shaped canal detected with the aid of CBCT.[9] Lim and Le Clerc have reported endodontic treatment of a C-shaped morphology in association with hypertaurodont teeth with pulpal calcification.[17] While this may be an uncommon variation, clinicians should be aware and appropriately plan the endodontic treatment to factor negotiating this complex anatomy.

In the present case, success could be attributed to the careful preoperative assessment and understanding of the root canal morphology, use of magnification, and meticulousness while cleaning and shaping the root canals. The pulp chamber cleaning was aided by the proteolytic, lipid affinity, and effervescent effect of carbamide peroxide with NaOCl.[18],[19] The intrachamber warmind of 5% NaOCl was effective in destroying collagen and reduced the time needed for eliminating the pulp tissue from the pulp chamber.[20],[21] The initial negotiation of the root canal was begun by utilizing EDTA carbamide peroxide gel (Glyde file prep) as the lubricating agent. This gel allows pulp tissue emulsification by breaking down collagen present in vital tissue and makes negotiating the canal and removal of pulp tissue easier.[22],[23] Following the extirpation of the pulp and preparation of the glide path further chemomechanical preparation of the canal utilized Smear Clear alternated wit h 5% NaOCl as the irrigating solution. The complex anastomosis and apical ramifications in the C-shaped canals cannot be mechanically negotiated, and instrumented and irrigation techniques should focus on increasing the efficacy of the irrigants to reach these non-negotiable root canal spaces. Alternating smear clear with NaOCl effectively eliminates debris and smear layer and prevents its compaction within the accessory canals and dentinal tubules.[24],[25] This allows a more effective reach of the irrigant within spaces not negotiated by mechanical instrumentation. The C-shaped canal isthmus was prepared and cleaned with ultrasonic tips to facilitate the debridement of these non-negotiable regions. Endoactivator sonic activation of irrigant was utilized to further increase the efficacy of the irrigating solution and debridement of the complex root canal system.

  Conclusions Top

This case underlies the importance of careful examination of hypertaurodont teeth as it may be associated with complex internal root canal anatomy like a C-shaped canal. This case also emphasizes the importance of meticulousness in treatment protocol to achieve predictable endodontic success in these complex anatomic morphology.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

Jafarzadeh H, Azarpazhooh A, Mayhall JT. Taurodontism: A review of the condition and endodontic treatment challenges. Int Endod J 2008;41:375-88.  Back to cited text no. 1
Bürklein S, Breuer D, Schäfer E. Prevalence of taurodont and pyramidal molars in a German population. J Endod 2011;37:158-62.  Back to cited text no. 2
Ruprecht A, Batniji S, el-Neweihi E. The incidence of taurodontism in dental patients. Oral Surg Oral Med Oral Pathol 1987;63:743-7.  Back to cited text no. 3
Ghaznawi HI. A clinical and radiographic survey of selected dental anomalies and conditions in a Saudi Arabian population. Saudi Dent J 1999;11:8-13  Back to cited text no. 4
Barker BC. Taurodontism: The incidence and possible significance of the trait. Aust Dent J 1976;21:272-6.  Back to cited text no. 5
Chaparro González NT, Leidenz Bermudez JS, González Molina EM, Padilla Olmedillo JR. Multiple bilateral taurodontism. A case report. J Endod 2010;36:1905-7.  Back to cited text no. 6
Llamas R, Jimenez-Planas A. Taurodontism in premolars. Oral Surg Oral Med Oral Pathol 1993;75:501-5.  Back to cited text no. 7
Shifman A, Chanannel I. Prevalence of taurodontism found in radiographic dental examination of 1,200 young adult Israeli patients. Community Dent Oral Epidemiol 1978;6:200-3.  Back to cited text no. 8
Radwan A, Kim SG. Treatment of a hypertaurodontic maxillary second molar in a patient with 10 taurodonts: A case report. J Endod 2014;40:140-4.  Back to cited text no. 9
Marques-da-Silva B, Baratto-Filho F, Abuabara A, Moura P, Losso EM, Moro A. Multiple taurodontism: The challenge of endodontic treatment. J Oral Sci 2010;52:653-8.  Back to cited text no. 10
Tsesis I, Shifman A, Kaufman AY. Taurodontism: An endodontic challenge. Report of a case. J Endod 2003;29:353-5.  Back to cited text no. 11
Do Nascimento AC, Marques AA, Sponchiado-Júnior EC, Garcia LF, de Carvalho FM. Endodontic treatment of hypertaurodontic mandibular molar using reciprocating single-file system: A case report. Bull Tokyo Dent Coll 2016;57:83-9.  Back to cited text no. 12
Baron C, Houchmand-Cuny M, Enkel B, Lopez-Cazaux S. Prevalence of dental anomalies in French orthodontic patients: A retrospective study. Arch Pediatr 2018;25:426-30.  Back to cited text no. 13
Fan B, Cheung GS, Fan M, Gutmann JL, Bian Z. C-shaped canal system in mandibular second molars: Part I--Anatomical features. J Endod 2004;30:899-903.  Back to cited text no. 14
Patil S, Doni B, Kaswan S, Rahman F. Prevalence of taurodontism in the North Indian population. J Clin Exp Dent 2013;5:e179-82.  Back to cited text no. 15
Bronoosh P, Haghnegahdar A, Dehbozorgi M. Prevalence of taurodontism in premolars and molars in the South of Iran. J Dent Res Dent Clin Dent Prospects 2012;6:21-4.  Back to cited text no. 16
Lim A, Le Clerc J. Endodontic treatment of a hypertaurodontic mandibular left second molar in a patient with many taurodonts combined with multiple pulp stones. Aust Endod J 2019;45:414-9.  Back to cited text no. 17
Cameron JA. The use of ultrasound and an EDTA-urea peroxide compound in the cleansing of root canals. An SEM study. Aust Dent J 1984;29:80-5.  Back to cited text no. 18
Shiozawa A. Characterization of reactive oxygen species generated from the mixture of NaOCI and H2O2 used as root canal irrigants. J Endod 2000;26:11-5.  Back to cited text no. 19
Landolo A, Amato M, Dagna A, Poggio C, Abdellatif D, Franco V, et al. Intracanal heating of sodium hypochlorite: Scanning electron microscope evaluation of root canal walls. J Conserv Dent 2018;21:569-73.  Back to cited text no. 20
Dash T, Mohan RP, Mannava Y, Thomas MS, Srikanth N. Effect of storage temperature and heating on the concentration of available chlorine and pH of 2.5% sodium hypochlorite. Saudi Endod J 2017;7:161-5.  Back to cited text no. 21
  [Full text]  
Pascon FM, Kantovitz KR, Rontani RM. Influence of cleansers and irrigation methods on primary and permanent root dentin permeability: A literature review. Braz J Oral Sci 2015;5:1063-69.  Back to cited text no. 22
Tambake RA, Daokar S, Patil K, Tambake SS, Mapari PS, Raktade P. Comparison of effect of ethylenediaminetetraacetic acid solution and ethylenediaminetetraacetic acid paste on canal transportation using cone beam computed tomography: An in vitro study. Endodontology 2018;30:50-4.  Back to cited text no. 23
  [Full text]  
Zehnder M. Root canal irrigants. J Endod 2006;32:389-98.  Back to cited text no. 24
Dua A, Dua D, Uppin VM. Evaluation of the effect of duration of application of smear clear in removing intracanal smear layer: SEM study. Saudi Endod J 2015;5:26-32.  Back to cited text no. 25
  [Full text]  


  [Figure 1], [Figure 2], [Figure 3], [Figure 4]


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