|Year : 2014 | Volume
| Issue : 1 | Page : 36-39
An endodontic management of mandibular third molar with five root canals
Dakshita Joy Sinha1, Ashish Amit Sinha2
1 Department of Conservative Dentistry and Endodontics, Kothiwal Dental College and Research Centre, Uttar Pradesh, India
2 Department of Pedodontics, Kothiwal Dental College and Research Centre, Uttar Pradesh, India
|Date of Web Publication||28-Feb-2014|
Dakshita Joy Sinha
Department of Conservative Dentistry and Endodontics Kothiwal Dental College and Research Centre, Uttar Pradesh
Source of Support: None, Conflict of Interest: None
The existence of several anatomical variations in the root canal system may contribute to failure of the root canal therapy. The planning and performing of endodontic therapy requires knowledge of the internal dental morphology. This paper reports the case of a left mandibular third molar that presented with five root canals; a case of unusual root canal morphology so as to demonstrate the anatomic variations in mandibular third molars. Root canal therapy and case management are described. This report highlights the importance of looking for additional roots and root canals so as to enable clinicians to treat a case successfully, which might have ended in failure.
Keywords: Anomalies, diagnosis, mandibular third molar, root canal morphology
|How to cite this article:|
Sinha DJ, Sinha AA. An endodontic management of mandibular third molar with five root canals. Saudi Endod J 2014;4:36-9
| Introduction|| |
A thorough understanding of root canal anatomy and morphology is required for achieving high levels of success in endodontic treatment. Failure to recognize variations in root or root canal anatomy can result in the failure of endodontic treatment. Hence, it is imperative that the clinician be well informed and alerted to the commonest possible variations. A 42% incidence of missed roots or canals was reported by Hoen and Pink in their analysis on teeth requiring re-treatment. 
Mandibular molars have a complex morphology.  The major variant in this group is the mandibular third molar having 3 roots.  Such variants have not been reported in the mandibular second molars,  but quite rarely been reported in the mandibular third molars. 
Till date there is no literature documented for presence of four rooted mandibular third molar with two distal and two mesial roots having five canals. The purpose of this article was to report the successful treatment of a case of rare anatomical variant of mandibular third molar.
| Case Report|| |
A 43-year-old male patient came to the dental office for endodontic treatment of the left mandibular third molar (#38), with history of pain. In the dental history, episodes of spontaneous pain were found since last three days. On examination the tooth showed a restoration on the occlusal surface. The tooth was painful to percussion and showed delayed response to cold test. The preoperative diagnostic radiograph of the left third molar revealed a restoration approaching the pulp with signs of periapical radiolucency with respect to two roots [Figure 1]. The clinical diagnosis of irreversible pulpitis with apical periodontitis was made and endodontic treatment was scheduled.
The restoration was removed and access was gained to the pulp chamber after administration of local anesthesia (2% Lignocaine with 1:100000 epinephrine), under rubber dam isolation. To gain sufficient access to the canals, the conventional access opening was modified into one that was wider. After careful inspection and examination under a surgical operating microscope (Global, India), it revealed the presence of five canal orifices and patency was ascertained using a small size K-file (Kerr, Orange, California). Five root canals: mesiobuccal (MB), middle mesial (MM), mesiolingual (ML), distobuccal (DB) and distolingual (DL) were identified [Figure 2]. The caries was removed from the coronal walls and the working length was established with the use of apex locator (Root ZX, J. Morita Inc.) Then the working length radiograph was taken and measured [Figure 3].
|Figure 2: Clinical view of the pulp chamber floor revealing 5 root canals orifices|
Click here to view
The canals were cleaned and shaped with hand K-files and nickel titanium rotary Pro Taper files (Dentsply Maillefer, Switzerland). The canals were sequentially irrigated using 5.25% Sodium hypochlorite and 17% EDTA during the cleaning and shaping procedure. The canals were thoroughly dried and obturation was done using F2 Pro Taper Gutta-percha and AH Plus sealer (Dentsply, Maillefer, Switzerland) [Figure 4].
The post-endodontic permanent restoration was completed with amalgam (DPI Alloy Fine grain silver tin dental amalgam alloy, Deepdent products, Delhi, India). The patient came after a month for follow-up and was found to be asymptomatic. He was advised to get a fixed prosthesis for #38 and the remaining missing teeth. A 1-year recall radiograph showed satisfactory healing [Figure 5].
| Discussion|| |
This case report points out the importance of keeping a third molar with a complete endodontic treatment. Third molars are often extracted, but if they are well-positioned in the arch, the maintenance of a third molar in function might be of some importance as distal abutment for a future prosthetic restoration and serve as potentially reliable candidates for auto-transplantation, thereby increasing the scope for retention of third molars.  Although now-a-days third molars are not root canal treated anymore or used as an abutment for bridge due to use of implant to replace missing teeth,  it was done in this case as the patient could not afford implant due to limited finances.
The endodontist must have comprehensive knowledge about root canal morphology. Many types of root curvatures and other anatomical variations may be present in teeth subjected to endodontic treatment. If a root canal system is not located, this may reduce the chance of treatment success.  Carr (1992) stated that the operating microscope greatly improved the ability of the endodontist to visualize and treat periapical pathology in endodontic surgery. It has also enhanced the practice of nonsurgical endodontics. The higher magnification and illumination is useful for access cavity preparation, instrumentation and obturation. It can improve the clinician's view of the complexity of the root canal anatomy and aid in the location of additional canals, fins or ribbons. 
Radiographic examination using conventional intraoral periapical views is important for the evaluation of the canal configuration. However, it has its inherent limitation to assess the root canal system completely. Recently, cone beam CT (CBCT) imaging has been shown to provide comparable images at reduced dose and costs to be considered as an alternative to multidetector CT imaging in endodontics.  Cotton et al. reported a number of useful applications in endodontics.  Matherne et al. suggested that CBCT imaging is useful even in identifying the root canal system. 
The root canal morphology of mandibular molars varies among different population groups. In another study involving 173 third mandibular molars, Gulabivala et al. found two separate roots in 68% of them, fused roots in 20% and a single C-shaped root in 11%. The majority of the mandibular third molars (61%) had two canals in this study. 
Guerisoli et al., reported a great variability in the anatomy of 269 third molars (155 maxillary and 114 mandibular). In 69.3% of the cases, the mandibular third molar displayed two root canals (a mesial and a distal). A mandibular third molar with three roots and another with an accessory root, which differed from the former due to its reduced size, were also reported. The authors concluded that mandibular third molars may have one, two or three roots and up to three canals. 
Sidow et al. reported that 17% percent of mandibular molars had one root (40% of which contained two canals), 77% had two roots, 5% had three roots and 1% had four roots. 
The case reported in this article was a rare case showing 3 mesial root canals in a mandibular third molar with no prior case reported till date of having two mesial and two distal roots.
The only tangible proof that the treated tooth was a mandibular third molar with two mesial and two distal roots would be after extraction examination, but the clinical image from the occlusal view, it was evident that major diameter of the third molar was the mesiodistal one, as expected from anatomic consideration.
The main problem, which was faced by the operator during the procedure, was that of taking radiographs with the clamp as patient had severe gagging. So dealing with such a case not only careful interpretation of radiograph and thorough knowledge of the normal as well as anatomical variations are required but also patience plays an important role.
| Conclusion|| |
Knowledge of biology, physiology and root canal anatomy is needed for the successful and predictable endodontic treatment outcome. The clinician should be astute enough to identify the presence of unusual numbers of roots and their morphology. Teeth with extra roots and/or canals pose a greater challenge to the dentist. A thorough knowledge of root canal anatomy and its variations, careful interpretation of the radiograph, close clinical inspection of the floor of the chamber, proper modification of access opening, patient compliance and patience on the part of the operator are essential for a successful treatment outcome and to avoid the occurrence of serious complications while commencing endodontic treatment in third mandibular molar teeth due to anatomical challenges.
| References|| |
Hoen MM, Pink FE. Contemporary endodontic retreatments: An analysis based on clinical treatment findings. J Endod 2002;28:834-6.
Mannocci F, Peru M, Sherriff M, Cook R, Pitt Ford TR. The isthmuses of the mesial root of mandibular molars: A micro-computed tomographic study. IntEndod J 2005;38:558-63.
Plotino G. A Mandibular Third Molar with Three Mesial Roots: A Case Report. JEndod2008;34:224-6.
Weine FS. The C-shaped mandibular second molar: Incidence and other considerations. J Endod 1998;24:372-5.
Gulabivala K, Aung TH, Alavi A, Ng YL. Root and canal morphology of Burmese mandibular molars. IntEndod J 2001;34:359-70.
Aly Ahmed HM. Management of third molar teeth from an endodontic perspective. Eur J Gen Dent 2012;1:148-60.
Friedman JW. The prophylactic extraction of third molars: A public health hazard. Am J Public Health 2007;97:1554-9.
CoutinhoFilho T, La Cerda RS, GurgelFilho ED, de Deus GA, Magalhães KM. The influence of the Surgical Operating Microscope in locating the mesiolingual canal orifice: A laboratory analysis. Braz Oral Res 2006;20:59-63.
Carr GB. Microscopes in endodontics. J Calif Dent Assoc 1992;20:55-61.
La SH, Jung DH, Kim EC, Min KS. Identification of independent middle mesial canal in mandibular first molar using cone-beam computed tomography imaging. J Endod2010;36:542-5.
Cotton TP, Geisler TM, Holden DT, Schwartz SA, Schindler WG. Endodontic application of cone-bean volumetric tomography. J Endod 2007;33:1121-32.
Matherne RP, Angelopoulos C, Kulild JC, Tira D. Use of cone-beam computed tomog-raphy to identify root canal systems in vitro
. J Endod 2008;34:87-9.
Gulabivala K, Opasanon A, Ng YL, Alavi A. Root and canal morphology of Thai mandibular molars. IntEndod J 2002;35:56-62.
Guerisoli DM, de Souza RA, de Sousa Neto MD, Silva RG, Pécora JD. External and internal anatomy of third molars. Braz Dent J 1998;9:91-4.
Sidow SJ, West LA, Liewehr FR, Loushine RJ. Root canal morphology of human maxillary and mandibular third molars. J Endod 2000;26:675-8.
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]