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 Table of Contents  
Year : 2019  |  Volume : 9  |  Issue : 2  |  Page : 144-147

Endodontic management of mandibular second premolar with Type IX canal configuration using cone-beam computed tomography

1 Dental Department, Prince Sultan Military Medical City, Riyadh, Saudi Arabia
2 Eastern Riyadh Dental Complex, Ministry of Health, Riyadh, Saudi Arabia
3 Restorative Department, Prince Abdulrahman Advanced Dental Institute, Riyadh, Saudi Arabia

Date of Web Publication3-Apr-2019

Correspondence Address:
Dr. Mohammed S Alenazy
P. O. Box 21437, Riyadh 11475
Saudi Arabia
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/sej.sej_101_18

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Thorough knowledge and understanding of root canal anatomy and morphology are crucial to achieve a successful endodontic treatment. However, the variation of the root canal morphology presents clinical difficulties that might lead to unfavorable outcomes. This case report describes endodontic management of a mandibular second premolar having three root canals of 26-year-old Saudi female. An axial view of cone-beam computed tomography (CBCT) revealed the presence of two fused roots and three root canals, the main canal trifurcated into three root canals at the middle third then merged in the C-shape canal. The configuration is called Sert and Bayirli's canal classification Type IX (1:3). The use of CBCT, in this case, contributed markedly through the diagnosis and endodontic management thereafter. In conclusion, the practitioner should be aware of unusual root canal anatomy in mandibular premolars and utilized all the appropriate armamentarium in diagnosing and treating these cases.

Keywords: Anatomical variations, cone-beam computed tomography, C-shape canal, mandibular second premolar, Type IX root canal configuration

How to cite this article:
Al-Shawwa SS, Al-Khairallah Y, Alenazy MS, Al-Dayel O. Endodontic management of mandibular second premolar with Type IX canal configuration using cone-beam computed tomography. Saudi Endod J 2019;9:144-7

How to cite this URL:
Al-Shawwa SS, Al-Khairallah Y, Alenazy MS, Al-Dayel O. Endodontic management of mandibular second premolar with Type IX canal configuration using cone-beam computed tomography. Saudi Endod J [serial online] 2019 [cited 2023 Feb 1];9:144-7. Available from: https://www.saudiendodj.com/text.asp?2019/9/2/144/255363

  Introduction Top

The aim of root canal treatment is to achieve chemomechanical debridement as well as filling the entire root canal system. Failure to perform that may lead to future complexity, such as missing canal and/or posttreatment disease.[1],[2] Therefore, a thorough understanding of internal and external root morphology of the teeth is crucial for successful endodontic treatment.[3]

Mandibular premolars considered as the most difficult teeth for root canal treatment because of their aberrant root canal system.[4] Different studies revealed the correlation between gender and ethnicity with anatomical variations and complexity of root canal morphology in particularly mandibular second premolars. Serman and Hasselgren[5] reported that the occurrence of having a multiple canal system and roots in mandibular premolars has a lower prevalence percentage of a female in comparison to male.

In the literature, several ways had been conducted to study the root canal morphology of second mandibular premolars.[6],[7],[8] Recently, cone-beam computed tomography (CBCT) scan made it possible to obtain images that have sufficient resolution to conduct studies of root canal anatomy.[8],[9]

Vertucci[10] and Zillich and Dowson[11] reported the incidence of having three canals in mandibular second premolar to be 0.0% and 0.4% respectively.

This case report presents diagnosis and successful nonsurgical endodontic treatment of a mandibular second premolar having an unusual occurrence of Sert and Bayirli's canal Type IX canal configuration and CBCT axial view has identified the C-shaped root canal morphology.

  Case Report Top

A 26-year-old Saudi female patient with no history of any systemic disease present to the clinic of Prince Abdulrahman Advanced Dental Institute, Riyadh, Saudi Arabia for full comprehensive treatment of her teeth. An initial dental examination revealed deep occlusodistal caries in the mandibular left second premolar (#35).

Radiographic evaluation revealed normal periodontium and the presence of multiple roots [Figure 1]a. CBCT was obtained from the patient to confirm root numbers and canals of the offending tooth. The CBCT was carried out using three-dimensional scanner planmeca ProMax (Planmeca Oy, Helsinki, Finland) and confirmed the presence of the two roots buccal and lingual with three canals were found, at the middle third two of the canals were in the buccal side “mesiobuccal (MB) and distobuccal (DB)” while the third one was in the lingual root [Figure 1]b. The axial image of the CBCT image also yielded a root canal morphology resembling C-shape configuration [Figure 1]c.
Figure 1: (a) Preoperative radiographic image of mandibular second premolar. (b) An axial plane of cone-beam computed tomography showing two roots (arrow) and three canals (the trifurcate of three canals at the middle third with radicular groove) of tooth #35. (c) The C-shape canal configuration

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After clinical and radiographic examination, the tooth was diagnosed initially as reversible pulpitis with normal periapical tissue. Inferior nerve block was given with 2% lidocaine and 1:10000 epinephrine then rubber dam was applied. After caries excavation, pathological pulp exposure was encountered. A nonsurgical root canal treatment was decided accordingly. The final pulpal diagnosis was changed to be asymptomatic irreversible pulpitis with normal periapical tissue. Access cavity was carried out under a dental operating microscope (MÖLLER–WEDEL International, Haag-Streit Surgical GmbH, Germany) to be modified in a triangular-shape to accommodate straight-line access for all canals [Figure 2]a. By using electrical apex locator (Root ZX, J. Morita, Kyoto, Japan), the working length was obtained and confirmed radiographically [Figure 2]b. The biomechanical phase was accomplished with protaper universal files (Dentsply, Maillefer, Ballaigues, Switzerland) up to size F3, besides the use of copious irrigation of 5.25% sodium hypochlorite in all steps. The canals were dried with sterile paper points and then filled with gutta-percha cones with lateral condensation technique and AH-26 sealer (Dentsply Maillefer, Ballaigues, Switzerland). Finally, the access cavity was filled with a composite filling (ChemFil, Dentsply Detrey, Germany) and restored with full-coverage crown [Figure 2]c.
Figure 2: (a) Working length confirmation. (b) A clinical image showing the triangular shape access cavity donates two buccal canals (mesiobuccal and distobuccal) and one canal in the lingual side. (c) Tooth # 35 with the final obturation and full crown coverage

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  Discussion Top

Successful endodontic root canal treatment mandates adequate biomechanical instrumentation and three-dimensional obturation to fill the entire canal space. The missed canal is one of the most frequent causes for root canal treatment failure.[1],[2]

Detection of morphological variations needs a careful interpretation of different angulated preoperative periapical radiographs.[12],[13] In general, in the mandibular premolars having three canals, the cervical part of that root is wider than the usual situation, with a little or mostly no taper.[14]

Root canal morphology variations were classified by Vertucci into eight types,[15] whereas Sert and Bayirl extended Vertucci classification by adding 14 types of root canal configurations.[7] The literature described the occurrence of Sert and Bayirli's Type IX root canal configuration and endodontic treatment as rarely documented.[16],[17],[18],[19],[20] Several authors had reported that the pulpal floor in the mandibular second premolar with three canals has two orifices in the buccal side (MB and DB) and one orifice lingually.[14],[21],[22],[23] The current report showed a similar pulpal map.

Currently, utilizing the advanced radiographic techniques such as CBCT is very helpful to explore the internal and external morphological variations.[1],[24],[25] CBCT had the capability of providing images with high diagnostic quality that has shorter scanning times and lower dosages in comparing to the conventional computed tomography (CT) scans. It is a noninvasive three-dimensional reconstruction imaging used as a practical tool in morphological analysis and endodontic applications.[26]

Two in vitro studies extensively analyze and describe the Type IX anatomic configuration of the root canal system in mandibular premolars by using microcomputed tomography.[16],[27] The evaluation of internal anatomy showed the occurrence of 7.8% in mandibular first premolars Type IX configuration, while the greater percentage of 16.2% was reported when mandibular premolar specifically had radicular grooves.

Teeth had radicular grooves more often to the attendant with complex and multiple canal morphologies, besides that they had a greater incidence of complicated root anatomies than single and simple canals.[28] Therefore, the availability of radicular grooves anatomies may influence the morphology of the root canal.[29] These results substantiate with this clinical case report, where the presence of a radicular groove was detected in the CBCT with variable root canal morphology.[16] Ordinola-Zapata et al.[16] reported that the mandibular premolars with three root canals are characterize by the presence of the pulp chamber as triangle-shaped, in which MB orifice distances to the lingual orifices are the greatest.

Until now there, are no clinical or laboratory studies were conducted to study the root canal morphology of the mandibular second premolar in the Saudi sup-population using of CBCT as a diagnostic tool. The available data were case reports, for example, case of two-rooted mandibular second premolars with three canals,[30] case of three-rooted mandibular second premolars with three canals[31] and two cases of four root canals were reported.[32],[33]

The current case showed a C-shaped canal configuration. There are only two published studies of the incidence of C-shape canal of mandibular molar teeth in Saudi Arabia.[8],[34]

The use of dental operating microscope will enhance a better visualization to locate an extra canal.[35] Moreover, fiber optic illumination, magnifying loops, 1% methylene blue staining technique and the bubbling effects with sodium hypochlorite might be useful in the exploration of additional canals.[36]

  Conclusion Top

This case report adds an extra confirmation for the considerable rare morphology of Sert and Bayirli's canal classification Type IX in the second mandibular premolar. The preoperative radiographic images, a correct outline of the access cavity, as well as the proper inspection of pulpal space all, are highly important for diagnosing and treating cases of internal morphological variations.

Declaration of patient consent

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

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

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Slowey RR. Root canal anatomy. Road map to successful endodontics. Dent Clin North Am 1979;23:555-73.  Back to cited text no. 4
Serman NJ, Hasselgren G. The radiographic incidence of multiple roots and canals in human mandibular premolars. Int Endod J 1992;25:234-7.  Back to cited text no. 5
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