Maxillary first and second molars having unusual palatal root canal morphology with spiral computed tomography findings: Two case reports

Gauri Malik; Saru Kumar Manchanda; Simranjeet Singh; Dheeraj Manchanda

doi:10.4103/cjhr.cjhr_94_20

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CASE REPORT

Year : 2021 | Volume : 8 | Issue : 4 | Page : 268-271

Maxillary first and second molars having unusual palatal root canal morphology with spiral computed tomography findings: Two case reports

Gauri Malik¹, Saru Kumar Manchanda², Simranjeet Singh³, Dheeraj Manchanda⁴
¹ Department of Conservative Dentistry and Endodontics, Christian Dental College, Ludhiana, Punjab, India
² Private Practioner, Absolute Dental Care, Faridabad, Haryana, India
³ Private Practioner, Happy Tooth Dental Clinic, Ludhiana, Punjab, India
⁴ Dental Surgeon, HCMS

Date of Submission	16-Jul-2020
Date of Acceptance	29-Jul-2021
Date of Web Publication	27-May-2022

Correspondence Address:
Gauri Malik
Department of Conservative Dentistry and Endodontics, Christian Dental College, Ludhiana - 141 002, Punjab
India

Source of Support: None, Conflict of Interest: None

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DOI: 10.4103/cjhr.cjhr_94_20

Abstract

A thorough knowledge of the basic root canal anatomy and its variations is necessary for the successful completion of the endodontic treatment. Maxillary first and second molars usually have three roots and three or four canals (two mesiobuccal canals, one distobuccal, and one palatal canal). The incidence of two palatal roots in maxillary molars is quite a rare dental anatomy. The article reports two palatal roots each in maxillary first and second molars found incidentally in two different cases. These cases provide an evidence of variations in the root canals in the palatal root of maxillary first and second molars. Clinicians should thoroughly examine the pulpal floor and radiographs for the possibility of additional canals.

Keywords: Four-rooted maxillary molars, spiral CT, two palatal roots, unusual palatal roots maxillary molars

How to cite this article:
Malik G, Manchanda SK, Singh S, Manchanda D. Maxillary first and second molars having unusual palatal root canal morphology with spiral computed tomography findings: Two case reports. CHRISMED J Health Res 2021;8:268-71

How to cite this URL:
Malik G, Manchanda SK, Singh S, Manchanda D. Maxillary first and second molars having unusual palatal root canal morphology with spiral computed tomography findings: Two case reports. CHRISMED J Health Res [serial online] 2021 [cited 2023 Mar 28];8:268-71. Available from: https://www.cjhr.org/text.asp?2021/8/4/268/346105

Introduction

Knowledge of both normal and abnormal anatomy of the root canal system is an extremely important point for planning and performing of the endodontic therapy. The main reasons for endodontic failure are the several anatomic variations existing in the root canal system, mainly in teeth with pulp necrosis. Unusual root and root canal morphologies associated with molars have been recorded in several studies in the literature.^[1],[2],[3]

In maxillary first molars, mesiobuccal (MB) roots tend to have more variations in the canal system followed by the distobuccal (DB) root, whereas the palatal root has the least.^[4] Anatomic characteristics of permanent maxillary molars are generally described as a group of teeth with three roots, two buccal, and one palatal and each root having one root canal.^[5]

The majority of the literature had focused on the morphology of the MB root and particularly on its mesiopalatal (MP) canal.^{[3],[6],[7],[8],[9]} The occurrence of a fourth canal ranges from 50.4%–95%, a fifth canal is 2.25%, and a few authors have also reported cases with six canals.^{[10],[11],[12],[13],[14],[15],[16],[17],[18],[19],[20],[21],[22]} However, Christie et al. have reported a variation in the number of roots and an unusual morphology of root canal systems in maxillary molars. Libfeld and Rotstein in a review and radiographic survey of 1200 teeth reported a 0.4% incidence of four-rooted maxillary second molars.^[23],[24]

The ideal method of precise determination of the root canal morphology of a tooth is the serial sectioning of the tooth, which is impractical in clinical situations. Therefore, other diagnostic methods such as spiral computed tomography (CT) are useful in such conditions to determine the root canal morphology.^[25]

The frequency of two palatal roots is low; however, a few cases have been reported in the literature. Stone and Stroner, reported variations in the palatal root of maxillary molars such as a single root with two separate orifices, two separate canals, and two separate foramina; two separate roots, each with one orifice, one canal, and one foramen; single root with one orifice, a bifurcated canal, and two separate foramina. Peikoff et al. reported a 1.4% incidence of four separate roots and four separate canals including two palatal roots in 520 maxillary molars.^[26],[27]

The article describes the cases of maxillary first and second molars each with two separate palatal roots. The first case discusses retreatment of a permanent maxillary first molar (26), in which an extra root was undiagnosed in the previous treatment and the second case discusses endodontic treatment in permanent maxillary second molar with two separate palatal roots.^[17]

Case Reports

Case 1

A 22-year-old female presented to the department of Conservative Dentistry and Endodontics, with a chief complaint of swelling and pain on chewing in the left upper back region. She gave a history of having undergone a root canal treatment of this tooth a few months back and was still symptomatic and the swelling appeared and subsided itself after every few days. On clinical examination, it was seen that there was an intraoral swelling in the left vestibule, and the tooth was tender on percussion.

An intraoral periapical radiograph was obtained which revealed three canals, i.e. MB, DB, and palatal (P1) obturated properly, but there was a large periapical radiolucency present with respect to the MB root [Figure 1]a. Furthermore, radiograph and clinical examination revealed the possibility of the presence of a second palatal root.

Figure 1: (a) Preoperative radiograph. (b) Working length radiograph. (c) Spiral CT X-ray. (d) Photograph showing lesion over mesiobuccal root. (e) Chamber floor showing five obturated canals. (f) Postobturation radiograph

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After removing the postendodontic restoration and on careful probing using DG16 explorer (Hu-Friedy, Chicago, IL), a small catch point was noted in a groove approximately 2 mm from the MB orifice in palatal direction. Furthermore, a hemorrhagic point was noted near the orifice of main palatal canal. A small amount of dentin covering the orifice of the second palatal canal was removed, and the conventional triangular access was modified to a trapezoidal shape to increase access. Missed additional canals MB2 and P2 canals were confirmed and ruled out for perforation using apex locator and careful clinical examination. Spiral CT was used to determine whether the second palatal canal was truly in the palatal root and what its morphology was [Figure 1]b.

Working length of the remaining canals, i.e. MB2 and P2 was determined using apex locator and with the help of RVG (Kodak [Figure 1]c). Canals were initially instrumented using No. 15 nickel-titanium file (Dentsply) and irrigated with 3% sodium hypochlorite (Vensons India, Bengaluru, India). Coronal flaring was done with Gates-Glidden drills (Dentsply Maillefer, Ballaigues, Switzerland) and canals cleaned and prepared with nickel–titanium files (Mani, Tochigi, Japan) using crown-down technique and irrigation with sodium hypochlorite and normal saline. Periapical surgery was performed to remove the granulation tissue present with respect to the MB root [Figure 1]d, and the remaining canals were obturated with gutta-percha and AH Plus sealer (Dentsply Maillefer Company, USA) [Figure 1]e. The final radiograph was obtained to evaluate the quality of obturation [Figure 1]f.

After completion of root canal treatment, tooth was restored with silver amalgam. The patient was recalled after 3 months and found to be asymptomatic.

Case 2

A 32-year-old patient presented to the department of Conservative Dentistry and Endodontics, with the chief complaint of spontaneous pain on the right side of the face for several days. Clinical examination revealed a right maxillary second molar with deep carious lesion. A diagnosis of irreversible pulpitis was made and tooth was prepared for nonsurgical endodontic therapy. Radiographic examination revealed the presence of four roots, two buccal, and two palatals [Figure 2]a. After confirmation of diagnosis, the patient received local anesthesia of 2% lidocaine with 1:200,000 epinephrine (Lox 2%, Neon Laboratories, Mumbai, India). Rubber dam (Hygienic) was placed, and access opening was made. The outline form was rectangular and four canal orifices of MB, DB, MP (PI), and distopalatal (DP) (P2) canals were located [Figure 2]b. The orifice of the distopalatal (DP) root was located 3 mm distal to the orifice of the main palatal canal. All canals were negotiated, patency was checked, and the working length was determined [Figure 2]c. The cleaning and shaping of canals were done by passive step-back technique and coronal flaring was performed using Gates Glidden Drills No. 2, 3, and 4 (Dentsply Maillefer, Ballaigues, Switzerland). Canals were irrigated with 3% NaOCl (Vensons India, Bengaluru, India) during instrumentation. The canals were obturated with selected master gutta-percha cones with AH Plus endodontic sealer (Dentsply Maillefer Company, USA) [Figure 2]d. The patient was recalled after 1 week for a postendodontic restoration in the form of the permanent amalgam restoration and a final radiograph was obtained[Figure 2]e.

Figure 2: (a) Preoperative radiograph. (b) Rubber dam placed and access opening showing four canals. (c) Working length radiograph. (d) Chamber floor showing obturated four canals. (e) Postobturation radiograph

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Discussion

The prevalence of maxillary first molars with two palatal canals is rare i.e. <2%.^[26] Literature is scarce regarding the presence of two separate palatal canals with separate orifices and separate exits.^[28] Furthermore, the incidence of four-rooted maxillary second molar is rare in the literature.^[9],[23] In 2003, Alani reported a case of bilateral four-rooted maxillary second molars that had two buccal and two palatal roots.^[29] The case report presented shows the presence of two separate palatal roots in maxillary first as well as second molar. In both cases, a large access was required to locate the two palatal canals. The access cavity on maxillary molars exhibiting two palatal canals should be wider than usual on the palatal aspect. The access outline will be trapezoidal rather than triangular.

In certain conditions, the root canals might be left untreated during the endodontic therapy if the practitioner is unable to detect their presence. These undetected extra roots or root canals are a major reason for the failure. Hence, the ability to locate all the canals in the root canal system is an important factor in determining the eventual success of a case.^[28] In this case report in the first case, the presence of a missed and incompletely obturated root canal could have probably led to the persistence of clinical symptoms and subsequent failure of endodontic therapy. The presence of the two separate palatal canals was confirmed by spiral CT. Tachibana and Matsumoto (1990) studied the applicability of computed tomography to endodontics.^[30] They concluded that this method allowed the observation of the morphology of the root canals, the roots, and the appearance of the tooth in every direction. Moreover, the image could be analyzed, altered, and reconstructed by the computer.

A nomenclature for additional canals in maxillary molars is given by Karthikeyan and Mahalakshmi 2010.^[31] According to them, in the palatal root, the main canal is palatal (P); the extra canals are termed MP or DP, depending on the location (mesial or distal) of the canal in relation to the main palatal canal. The etiology behind the formation of extra roots is unclear. In supernumerary roots, the formation could be related to external factors during odontogenesis or penetration of atavistic gene. Curzon also suggests that additional rooted molar trait has a high degree of genetic penetrance.^[32]

Floor of the pulp chamber and wall anatomy provide a guide to determining what morphology is actually present.^[4] Although there are inherent limitations, radiographs of different angulations provide a clue to the type of canal configuration present. They suggested using surgical operative microscope to find extra orifices.^[33] Furthermore, spiral computed tomography (CT) is used to ascertain the three-dimensional morphology of the tooth.^[30]

Conclusion

Knowledge of possible variations in the internal anatomy of human teeth is important for successful endodontic treatment. Anatomic variations can occur in any tooth, and maxillary molars are no exception. Successful endodontic management of maxillary molars with two palatal root canals has been presented. Careful interpretation of the radiograph with the help of RVG, close clinical inspection of the floor of the chamber, and proper magnification of the chamber floor using surgical microscope is essential for a successful treatment outcome. For successful root canal therapy, it is must to locate all the canals and perform through cleaning and shaping to achieve three-dimensional seal and promote a normal healing process.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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