International Journal of Oral Health Sciences

: 2013  |  Volume : 3  |  Issue : 2  |  Page : 113--116

Endodontic management of maxillary second molar having unusual anatomy with three mesiobuccal root canals: A rare case report

Purav Mehta, Deepak Raisingani, Rachit Mathur, Divya Jindal 
 Department of Conservative Dentistry and Endodontic, Mahatma Gandhi Dental College and Hospital, Jaipur, Rajasthan, India

Correspondence Address:
Purav Mehta
Department of Conservative Dentistry and Endodontic, Mahatma Gandhi Dental College and Hospital, Jaipur, Rajasthan


Variations in the dental anatomy are found in all teeth. Knowledge of these variations, particularly concerning the location and treatment of all canals, is very important for the success of the endodontic therapy. The purpose of this case report is to present a clinical case of a maxillary second molar with three mesiobuccal canals. This report serves to remind clinicians that such anatomical variations should be taken into account during endodontic treatment of the maxillary molars.

How to cite this article:
Mehta P, Raisingani D, Mathur R, Jindal D. Endodontic management of maxillary second molar having unusual anatomy with three mesiobuccal root canals: A rare case report.Int J Oral Health Sci 2013;3:113-116

How to cite this URL:
Mehta P, Raisingani D, Mathur R, Jindal D. Endodontic management of maxillary second molar having unusual anatomy with three mesiobuccal root canals: A rare case report. Int J Oral Health Sci [serial online] 2013 [cited 2022 Jun 26 ];3:113-116
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The principal goal of endodontic therapy is healing of the periapical tissues. This is gained by elimination of bacteria and infected tissues from root canals and prevention of reinfection. [1] Understanding root canal morphology is one of the most important steps in successful root canal treatment. Fahid and Taintor [2] stressed that if a clinician cannot locate the root canal, it cannot be properly cleaned, shaped, filled and sealed. Insufficient knowledge of the anatomy of the teeth is one of the main reasons for failure of root canal therapy; [3] knowledge of anatomical aberrations will markedly decrease the failure rate. [1]

For this reason, during the diagnosis and treatment phases of the maxillary molars, a clinician must be aware of anatomical variations. [4] A number of studies have investigated the root canal morphology of maxillary second molars in the literature. These studies have reported the incidence of a second mesiobuccal (MB 2 ) canal and its anatomical aberrations. Kulild and Peters [5] stated that the existence of a second mesiobuccal canal in maxillary first and second molars is fairly common. Some case reports and studies showed anatomical variations of maxillary second molars, such as four roots, c-shape canal, Taurodontism, two distobuccal canals, three buccal roots and a second palatal root canal.

In maxillary second molars, mesiobuccal roots tend to have more variations in the canal system, followed by the distobuccal root, whereas the palatal root has the least. This case report intensifies the complexity of maxillary 2 nd molar variation. It presents endodontic treatment of a maxillary second molar having five canals and, among them, three are found in the mesiobuccal root, and stresses that clinicians should bear in mind that such anatomical differences might be encountered during treatment.

 Case Report

A 29-year-old male patient reported to the Department of Conservative Dentistry and Endodontics, Mahatma Gandhi Dental College and Hospital, Jaipur, Rajasthan, with a complaint of pain in his maxillary right second molar. The patient had no significant medical history. Clinical and radiological examinations of the tooth revealed profound caries lesions [Figure 1]. The patient reported subjective symptoms of prolonged sensitivity to hot and cold and the recent onset of pain. The objective symptoms were observed as mild percussion sensitivity and no response to heat and cold test, with widening of periodontal membrane space radiographically and lack of swelling of the surrounding tissue. Therefore, the patient was diagnosed with chronic irreversible pulpitis.

After a local anesthetic was administered by use of 2% Lidocaine with 1:100,000 epinephrine (LA BRAND), a rubber dam was applied and the access cavity was prepared. The access opening was completed and the mesiobuccal (MB1), distobuccal (DB) and palatal root canals were easily found. The careful examination of the floor of the pulp chamber with surgical loupes (EyeMag® with ×2.5 magnification, Dental Microscopes and Dental Loupes by Carl Zeiss Meditec) and DG-16 Endodontic explorer used to locate the extracanal orifice showed 2 nd mesiobuccal root canals (MB2). Ultrasonic tips (Dentsply Maillefer, Ballaigues, Switzerland) were used to remove the dentin. Again, careful examination of the floor of the pulp chamber showed an additional root canal orifice near the MB2 canal orifice. It was located approximately 1 mm distally from the MB2 canal orifice, and away from the MB1 canal orifice. This canal is considered as the 3 rd mesiobuccal canal (MB3) [Figure 2]. The working lengths were determined with an apex locater (Propex II, Dentsply Maillefer, Switzerland) and controlled radiographically [Figure 3]. The radiograph demonstrated that MB1 and MB2 were fused in the apical third root canals while MB3 was completely separated. Steep curvature was found in the apical third of the distobuccal canal. The cleaning and shaping of the canals were done by a passive Crown Down technique using K 3 Ni-Ti rotary files for MB1 and DB (0.04% taper SybronEndo), profile (0.02% taper) for MB2 and MB3 and Protaper Ni-Ti rotary files for palatal canal (Dentsply Maillefer, Ballaigues, Switzerland). Root canal filling done with appropriately sized gutta-percha points (Dentsply Maillefer and SybronEndo, respectively) and Sealapex sealer (Kerr Co., Romulus, MI, USA) [Figure 4]. On completion of the root canal therapy, the tooth was restored with composite resin materials. A final radiograph showed the presence of three mesiobuccal root canals [Figure 5].{Figure 1}{Figure 2}{Figure 3}{Figure 4}{Figure 5}


A maxillary second molar normally contains three roots, with three root canals in each root. A number of recent studies have reported abnormal maxillary molars, roots and canals, and most of them have investigated a second mesiobuccal canal. These studies have reported widely varied percentages of patients with a second mesiobuccal canal in the maxillary second molar (24% Sempira and Hartwell; [6] 93.7% Kulild and Peter [5] ). Other studies suggested the prevalence of a third mesiobuccal canal in the maxillary second molar as in vitro. [1],[7] Caliskan et al. [8] reported in their in vitro study that using a clearing technique, [4] 16% of the maxillary second molars contained three mesiobuccal canals. These third mesiobuccal canals in the maxillary second molars were quite difficult to discover. Their small size and their superposition over another root canal [9] often accounted for the difficulty in locating the extracanal(s).

A preoperative radiograph might not produce clear evidence of their existence. Therefore, before the operation, multiple preoperative radiographs with various angulations are recommended to assist in detecting the extra canal(s). In addition, careful examination of the floor of the pulp chamber is essential to ensure clinical success. In some case reports, root and canal abnormalities of the maxillary second molar were shown. Jafarzadeh et al., [10] Zmener and Peirano [11] and Fahid and Taintor [2] reported three separate buccal roots. Wang et al. [12] reported a maxillary second molar with four roots and five canals (two of them mesiobuccal, two of them palatal and the other a distal root). Ozcan et al. [13] reported a maxillary second molar with three mesiobuccal canals.

In the dental literature, a third mesiobuccal canal was reported clinically by Beatty [14] in the maxillary first molar, but there are no available data that report the existence of a third mesiobuccal canal in a maxillary second molar. The present paper illustrates a third mesiobuccal canal in a maxillary second molar with three roots. Peikoff and his colleagues' [15] report had sic variants of the morphology of the root canal system, and none were associated with our case. However, Vertucci's [16] classification of the root canal systems reported 23 types, with additional types. Type 16 in Vertucci's classification was compatible with our case of three mesiobuccal canals. The root canal system of the maxillary second molars is complex, and treatment of these teeth is difficult. [17] The prognosis for second molars depends on the detection of the extra canal(s) and properly cleaning, shaping and sealing the molar. Failing to detect and treat a canal might cause treatment failure. The most important factor in the detection of extracanals is the practitioner's commitment to high-quality patient care.


Successful endodontic treatment begins with proper clinical and radiographic examinations. A practitioner must be vigilant, as variations of root and canal anatomy might be encountered at any time during treatment. These anatomic variations directly affect the treatment prognosis.


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