|Year : 2019 | Volume
| Issue : 1 | Page : 129-132
Maxillary second molar with single root and single canal: A case series
Parul Bansal, Preeti Mishra, Vineeta Nikhil, Shalya Raj, Apoorva Jain
Department of Conservative Dentistry and Endodontics, Subharti Dental College, Meerut, Uttar Pradesh, India
|Date of Web Publication||19-Jun-2019|
Dr. Parul Bansal
Department of Conservative Dentistry and Endodontics, Subharti Dental College, Meerut, Uttar Pradesh
Source of Support: None, Conflict of Interest: None
Maxillary second molars are generally considered to have three roots and three or four canals. In the literature, various cases of maxillary second molars have been reported with more number of roots and root canals, but only very few cases have been reported with less number of roots and root canals. This article reports about the diagnosis and endodontic management of maxillary second molars with single root and single canal, as failure to identify such configuration may lead to poor prognosis due to excessive removal of the dentin in search of canals.
Keywords: C-shaped canal, maxillary molar, second molar, single canal, single root
|How to cite this article:|
Bansal P, Mishra P, Nikhil V, Raj S, Jain A. Maxillary second molar with single root and single canal: A case series. Endodontology 2019;31:129-32
| Introduction|| |
The standard configuration of maxillary second molars has been described to have three roots and either three or four canals, with the fourth canal usually being the second mesiobuccal (MB2). Most of the researches have focused on more number of roots,,, and root canals, and only very few studies are there with lesser number of roots and root canals in the maxillary second molar. Presence of single root and single canal is commonly found in mandibular second molar, and only few textbooks describe the possibility of single root and single canal in maxillary second molar. Researchers have found only 0%–3.1% incidence of occurrence of single root and single canal in maxillary second molar.
| Case Reports|| |
A 25-year-old male patient reported with the chief complaint of pain in his upper right back tooth region for the last few days. Pain was severe in intensity, nonradiating, aggravated at night, and was spontaneous in nature. Clinical examination of that quadrant revealed deep caries in relation to the maxillary right second molar. Radiographic examination of the tooth revealed radiolucency involving the pulp with no signs of any periapical pathology [Figure 1]a. Based on clinical and radiographic features, a diagnosis of symptomatic irreversible pulpitis was established and endodontic treatment was planned. Preoperative radiographic examination gave the suspicion of presence of single root and single canal. Cone-beam computed tomography (CBCT) was done to confirm the canal anatomy and to identify any other canal, if present. CBCT images confirmed the presence of a single large canal at the center of a single conical root [Figure 1]b and [Figure 1]c. This configuration was present bilaterally.
|Figure 1: (a) Preoperative radiograph, (b) Axial-section cone-beam computed tomography, (c) Coronal-section cone-beam computed tomography, (d) Working-length radiograph, (e) Master cone radiograph, (f) Postoperative radiograph|
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Medical history of the patient was noncontributory. After administration of local anesthesia under rubber dam isolation, access cavity was prepared. A single large oval canal was located at the center of the tooth. No further dentin was removed in search of any other canal. Working length was measured using an electronic root canal length-measuring device (CanalPro™, Coltene/Whaledent Inc., Cuyahoga Falls, Ohio, USA) and confirmed radiographically [Figure 1]d. Canal preparation was done using ISO hand K-files (Mani, Germany) in a step-back manner till size no. 80. After each instrument, the canal was irrigated with 2 ml, 3% sodium hypochlorite (Novodent Equipments and Materials Ltd., Mumbai, India) and final rinse was done with 17% ethylenediaminetetraacetic acid (DeSmear, Anabond, Chennai, India) and saline. The canal was dried using sterile paper points and obturated with cold lateral compaction technique using Gutta-percha and AH Plus® Sealer (Dentsply, Maillefer, USA). A postobturation radiograph was taken to verify the obturation [Figure 1]e and [Figure 1]f. The patient was asymptomatic during the follow-up period.
A 20-year-old male patient presented with the chief complaint of severe pain in his left upper back tooth region for the last few days. On clinical and radiographic examination, a diagnosis of irreversible pulpitis was established and root canal treatment was planned. On preoperative radiograph, only a single large canal could be traced at the center of the single conical root [Figure 2]a. CBCT was done to confirm the canal anatomy [Figure 2]b,[Figure 2]c,[Figure 2]d. This configuration was present unilaterally; on the right side, there were three roots and three canals [Figure 2]e. After administration of local anesthesia and rubber dam application, access to the canal was gained [Figure 2]f. After working-length determination, biomechanical preparation was done using ISO hand K-files in a step-back manner till size no. 70 [Figure 2]g. Obturation was done using cold lateral condensation technique [Figure 2]h and [Figure 2]i.
|Figure 2: (a) Preoperative radiograph, (b) cone-beam computed tomography axial sections through cervical, middle, and apical roots, (c) cone-beam computed tomography coronal section, (d) cone-beam computed tomography sagittal section, (e) cone-beam computed tomography axial section showing unilateral occurrence, (f) clinical photograph, (g) Working-length radiograph, (h) master cone radiograph, (i) postoperative radiograph|
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A 45-year-old female patient presented with the chief complaint of pain in her upper left back tooth region since last two to three days. On clinical and radiographic examination, a diagnosis of irreversible pulpitis with apical periodontitis was established and root canal treatment was planned [Figure 3]a. Preoperative radiograph gave the impression of the presence of a single canal in a single root, which was confirmed with CBCT analysis [Figure 3]b,[Figure 3]c,[Figure 3]d. This configuration was present unilaterally; on the right side, there were three roots and three canals. After administration of anesthesia, under rubber dam isolation, access was gained to the single large canal. Canal orifice was present little distally rather being at the center. The canal was prepared in a step-back manner and obturated with lateral compaction technique [Figure 3]e and [Figure 3]f.
|Figure 3: (a) Preoperative radiograph, (b) cone-beam computed tomography axial section, (c) cone-beam computed tomography sagittal section, (d) cone-beam computed tomography coronal section, (e) master cone radiograph, (f) Master cone radiograph|
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| Discussion|| |
Most studies on anatomical variations of maxillary molars appear to deal with maxillary first molars, as anatomical variations in second molars are not so common. Only few cases of maxillary second molars have been reported with variations in the number of roots and root canals such as two MB roots, three MB canals, two palatal roots with two or three root canals, and a second distobuccal (DB) canal.,,,
Peikoff et al. conducted a retrospective study of 520 endodontically treated maxillary second molars and have classified the anatomical root and canal variations found in maxillary second molar into six variants: (1) Three separate roots (MB, DB, and P-palatal) with one canal in each root; (2) Three separate roots (MB, DB, and P) and four canals (two in the MB root); (3) Three roots but MB and DB canals combine to form a common buccal (B) with a separate P canal; (4) One B and one P canal with a single canal in each; (5) Single canal in a single conical root; and (6) four separate roots – MB and DB and two palatal roots – a mesiopalatal and a distopalatal root. This study revealed that occurrence of the “standard” configuration in maxillary second molars, i.e. three roots with three or four canals was most frequent (56.9%). In this study, Peikoff et al. concluded that 3.1% of maxillary second molars had one root and one canal. According to Peikoff's categorization of the morphology of the root canal system, the variant identified in our case would be considered variant 5.
The incidence of fused roots in maxillary second molars was investigated by Kim et al. in a Korean population using CBCT and was found to be 10.7%. Similarly, Zhang et al. in a Chinese population using CBCT found the incidence of a single root in maxillary second molars to be 10%. When only one root is present, root canal system may commonly present with a single broad root canal or two canals that may or may not join or a C-shaped canal.
Carlsen et al. investigated 104 single-rooted maxillary second molars from a Scandinavian population by sectioning technique and found that 25.96% of single-rooted maxillary second molars had a single canal at the mid-root level.
Hartwell and Bellizzi in their study of 176 teeth concluded that the occurrence of maxillary second molars with a single root and a single canal was 0.6%. Libfeld and Rotstein in an Israel population reported that this configuration was present in 0.5% of teeth.
According to Wang et al., the occurrence of maxillary second molars with single root and a single canal is very rare. Ng et al. studied 77 maxillary second molars collected from Burmese patients but failed to find even a single tooth with single root and a single canal.
From a clinical standpoint, if an atypical anatomic configuration is identified in a tooth, the contralateral tooth should also be imaged. In addition, it is suggested to take additional radiographs from mesial and/or distal angulations for more diagnostic information. Sabala et al. analyzed 501 dental records for bilateral presence of root canal aberrations. They reported that unusual canal anatomy is bilateral in 60% of the cases. In fact, Sabala et al. stated that the more rare the anomaly, the more probable it was for it to be bilateral.
On the other hand, in the previously mentioned retrospective study done by Peikoff et al., the authors stated that anatomical symmetry in contralateral pairs was similar but not always perfect. Yew and Chan studied clinical records and radiographs of 832 endodontically treated mandibular first molars in a Chinese population and reported a bilateral incidence of 67% of an extradistal root in these teeth.
In a Caucasian female patient, Fava et al. encountered all the 4 s molars (both maxillary and mandibular) with single root and a single canal. Whereas, Ajeti et al. found this rare canal configuration in maxillary second molars of both the quadrants but not in mandibular second molars. In our report, in case 1, this configuration was present bilaterally, whereas in cases 2 and 3, it was present unilaterally and was confirmed in CBCT images.
Conventional intraoral periapical radiographs are an important diagnostic tool in endodontics for assessing the root morphology and canal configuration. The canal configuration of maxillary second molar seen in our cases was suspected with intraoral periapical radiograph. Although the importance of conventional radiography cannot be underestimated, it has some pitfalls. Recently introduced newer diagnostic aids such as CBCT and spiral computed tomography have overcome the disadvantages of conventional radiography by producing three-dimensional images. In our cases, CBCT was done to confirm the canal configuration and the absence of any other canal.
| Conclusion|| |
Although the occurrence of maxillary second molar with a single root and a single canal is not high, diagnosing these unusual cases at its early treatment stage is of significance for the success of endodontic treatment. CBCT must be used in these cases when conventional radiographic examination is not conclusive in identifying the aberrations in the canal anatomy in order to prevent excessive dentin removal in search of other canals.
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|| |
Deveaux E. Maxillary second molar with two palatal roots. J Endod 1999;25:571-3.
Libfeld H, Rotstein I. Incidence of four-rooted maxillary second molars: Literature review and radiographic survey of 1,200 teeth. J Endod 1989;15:129-31.
Fahid A, Taintor JF. Maxillary second molar with tree buccal roots. J Endod 1998;14:181-3.
Kottoor J, Hemamalathi S, Sudha R, Velmurugan N. Maxillary second molar with 5 roots and 5 canals evaluated using cone beam computerized tomography: A case report. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010;109:e162-5.
Peikoff MD, Christie WH, Fogel HM. The maxillary second molar: Variations in the number of roots and canals. Int Endod J 1996;29:365-9.
Kim Y, Lee SJ, Woo J. Morphology of maxillary first and second molars analyzed by cone-beam computed tomography in a Korean population: Variations in the number of roots and canals and the incidence of fusion. J Endod 2012;38:1063-8.
Zhang R, Yang H, Yu X, Wang H, Hu T, Dummer PM, et al.
Use of CBCT to identify the morphology of maxillary permanent molar teeth in a Chinese subpopulation. Int Endod J 2011;44:162-9.
Carlsen O, Alexandersen V, Heitmann T, Jakobsen P. Root canals in one-rooted maxillary second molars. Scand J Dent Res 1992;100:249-56.
Hartwell G, Bellizzi R. Clinical investigation of in vivo
endodontically treated mandibular and maxillary molars. J Endod 1982;8:555-7.
Wang Y, Hui X, Huang DM. Maxillary second molar with curved single root and single canal: A case report. Hua Xi Kou Qiang Yi Xue Za Zhi 2011;29:104-5.
Ng YL, Aung TH, Alavi A, Gulabivala K. Root and canal morphology of Burmese maxillary molars. Int Endod J 2001;34:620-30.
Sabala CL, Benenati FW, Neas BR. Bilateral root or root canal aberrations in a dental school patient population. J Endod 1994;20:38-42.
Yew SC, Chan K. A retrospective study of endodontically treated mandibular first molars in a Chinese population. J Endod 1993;19:471-3.
Fava LR, Weinfeld I, Fabri FP, Pais CR. Four second molars with single roots and single canals in the same patient. Int Endod J 2000;33:138-42.
Ajeti N, Vula V, Apostolska S, Pustina T, Kelmendi T, Emini L, et al
. Maxillary second molar with single root and single canal case report. Open J Stomatol 2015;5:47-52.
[Figure 1], [Figure 2], [Figure 3]