Saudi Endodontic Journal

: 2023  |  Volume : 13  |  Issue : 1  |  Page : 28--35

Effective management of mandibular second premolar with root anomalies: Review of literature with case analysis

Ashwaq Faia Asiri 
 Department of Restorative Dental Sciences, College of Dentistry, Majmaah University, AL-Majmaah, Saudi Arabia

Correspondence Address:
Dr. Ashwaq Faia Asiri
Department of Restorative Dental Sciences, College of Dentistry, Majmaah University, AL-Majmaah 11952
Saudi Arabia


The enigma of successful treatment of mandibular second premolars with taurodontism has been explored for very long due to its rarity of occurrence. This case report aimed to enumerate the successful nonsurgical endodontic management of left mandibular second premolar #35 with three roots and taurodontism. A 34-year-old Saudi male patient with a noncontributory medical history was referred from the prosthodontic department for nonsurgical root canal treatment of tooth #35. Clinical examination revealed rotated clinical crown with caries related to tooth #35. Pulp sensibility cold test of the tooth showed no response, with the absence of pain on percussion and/or visible pocket depth. Radiographic examination showed long and deep pulp chamber and rotated and curved roots with broken apical lamina dura. The tooth was diagnosed with necrotic pulp and asymptomatic apical periodontitis. After making an access to the pulp chamber, two orifices were easily detected while the third one was found by the aid of surgical microscope. The canals were cleaned and shaped using ProTaper Gold file and then obturated with BioCeram Sealer and Gutta-Percha points, using hydraulic bonded obturation technique. Tooth immediately received the final crown. Clinical and radiographical examination after a 3-month follow-up revealed successful peri-apical healing with no symptoms. A literature search was organized to review the past publications about management of mandibular second premolar with taurodontism or anomalies in the root canal system. The search was focused on cases reported in Medline, Scopus, and Google Scholar databases. The conclusion of the seven selected studies and reported cases revealed that proper visualization with advanced microscopes or computer imaging radiographs, negotiation of the root canals, and efficient instrumentation and obturation enhance endodontic success.

How to cite this article:
Asiri AF. Effective management of mandibular second premolar with root anomalies: Review of literature with case analysis.Saudi Endod J 2023;13:28-35

How to cite this URL:
Asiri AF. Effective management of mandibular second premolar with root anomalies: Review of literature with case analysis. Saudi Endod J [serial online] 2023 [cited 2023 Feb 3 ];13:28-35
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Conventional endodontic treatment has a reported success rate of 89%–94% in vital and nonvital pulps.[1] There are several factors such as variations in tooth anatomy and morphology, periapical condition of the teeth, proper coronal restoration, and an apical seal or any tooth anomaly which greatly influence the treatment plan.[1],[2] The variable and complex internal anatomy of the root canal system often is a major determinant for the successful endodontic outcome.[3] Therefore, it is important for clinicians to identify any variation in the morphology of tooth before performing any endodontic procedure.[4],[5]

Assessment of root canal morphologies and the impending possible variations are imperative for the success of endodontic management.[6],[7],[8] An ideal radiological evaluation always facilitates the negotiation, instrumentation, and obturation with complete three-dimensional seal.[9] Renowned knowledge about the variations in root canal morphology can prevent endodontic failure and associated complications.[10],[11]

The complexity of the canal anatomy has made management of mandibular premolars a possible challenge.[12] This is often attributed to extreme morphological variations in the root canal. Mandibular second premolar often has a wider buccolingual root canal morphology with two pulp horns.[13] The canal is often found to be oval near the cervical line and tends to take a rounder form toward the middle part of the root.[14] Vertucci exclaimed that 97.5% of the mandibular premolars were reported to have single root canals.[12],[15] Variations are also presented as double canal extending from pulp chamber to the apex or single broad root canal which is bifurcated into two root canals more toward the foramen. Previous studies by Zillich and Dowson and De Moor demonstrated three root canals in mandibular second premolars.[16] Nevertheless, Wiene's Type IV configuration often poses challenge to negotiation of the lingual canal, as it diverges from the main canal at a sharp angle and the lingual inclination of the teeth directs the instrumenting file buccally.[10],[17] Anatomic variations and root canal complexities in mandibular second premolars have predilections to gender and ethnicity. Greater prevalence was found to be in blacks and in male population.[18]

Further, greater part of variations of root canal morphology is associated with dental anomalies. One such contributing dental anomaly is taurodontism. “Taurodontism is a change in tooth shape caused by the failure of Hertwig's epithelial sheath diaphragm to invaginate at the proper horizontal level.”[19] Taurodontism is a morpho-anatomical change, characterized by a vertically elongated pulp chamber, apically displaced pulpal floor with bifurcation or trifurcation of the roots.[20] Further, taurodontism also shows a variation in which the body of the tooth is enlarged and roots are reduced in size, affecting the long-term outcome of the endodontic treatment.[20] In 1973, Zillich and Dawson first reported an incidence rate of 2.1% and 0.4% of taurodontism with two or more roots in mandibular first and second premolars, respectively.[21],[22]

Mandibular premolars and specifically second premolars have noticeable morphological divergence in the root canal system.[23] Evidence-based literature also reports that mandibular second premolar has the incidence of three roots in mandibular second premolar varied between 0.01% and 0.5%.[16] Likewise, the prevalence of taurodontism among second premolar varies according to the study populations.[24],[25] The present study intends to present the successful management of a unique case of a male patient who underwent nonsurgical root canal treatment for mandibular second premolar with taurodontism and three roots.

 Case Report

A 34-year-old Saudi male patient was referred from the prosthodontic clinic for a recommended nonsurgical root canal treatment of mandibular second premolar. The patient's dental and medical histories recorded were noncontributory. Written valid consent was obtained by the Endodontic Department of Riyadh Elm University from the patient before treatment was started. The chief complaint of the patient remained that of a cavitated tooth, with no signs of pain or any other concern. However, the patient had a history of multiple previous dental treatments from the private clinics.

Clinical examination revealed rotated clinical crown with caries related to tooth #35 [Figure 1]. Pulp sensibility cold test of the tooth showed no response, with the absence of pain on percussion and/or visible pocket depth. During the first visit, two preoperative periapical radiographs were taken. It showed a long and deep pulp chamber and the presence of three rotated and curved roots with broken apical lamina dura [Figure 2] and [Figure 3]. Eventually, the tooth was diagnosed with necrotic pulp and asymptomatic apical periodontitis.{Figure 1}{Figure 2}{Figure 3}

After a thorough evaluation of the clinical scenario, a nonsurgical endodontic treatment was planned. The patient was given a mandibular block anesthesia with 2% lidocaine with 1:100,000 epinephrine. The tooth was isolated with rubber dam and the access cavity for the pulp chamber was made. Two orifices were easily detected while the third one was found by the aid of surgical microscope (EXTARO 300 from ZEISS). Working length was determined with electronic apex locater (Root ZX II, J. Morita) and an additional radiograph with K-file confirming the root canal lengths [Figure 4]a.{Figure 4}

Cleaning and shaping of the canal was done through ProTaper Gold SX, S1, S2, F1, F2, and F3 (Dentsply Sirona, SA, Engine Rotary Files, MP-A0410221G0103). In addition, 5.25% sodium hypochlorite and ethylenediaminetetraacetic acid (EDTA) 17% solutions were used to irrigate the canals. During the second visit, canals were obturated with BioCeram Sealer (Cerafill RCS, Saudi Arabia,Prevest DenPro 40037) and BioCeram Gutta-Percha points (EndoSequence BC Points, Brasseler, USA), using hydraulic bonded obturation technique [Figure 4]b and [Figure 4]c. The tooth immediately received final crown and remained asymptomatic with no periapical lesion during the 3 months of follow-up period [Figure 5].{Figure 5}

 Literature Search Strategy

A literature search was organized from July 2021 to December 2021 to review the past publications about management of mandibular second premolar with taurodontism or anomalies in the root canal system with focus on cases reported in Medline, Scopus, and Google Scholar databases. The search strategy involved a combination of search keywords including “MANDIBULAR” “SECOND” “PREMOLAR,” “TAURODONTISM,” and “ROOT CANAL,” “ANOMALIES” based on which 388 articles were identified from the three databases (Medline – 106, Scopus – 88, and Google Scholar – 184). Narrowing down to articles published in English language only, abstracts were further reviewed. Finally based on the reporting criteria, management strategy of the mandibular second premolar with root anomalies, and the presence of taurodontism, 7 studies were selected for review. Six of the selected articles were single case reports whereas one of the studies had reported two cases [Table 1].{Table 1}


Literature review of this subject reveals greater variations in the root canal system of the mandibular premolars including cases with taurodontism, multiple canals, and the presence of root bifurcation. The average age of the patients reported with second mandibular root anomalies ranged from 12 to 46 years. Majority of the reported patients were males (n = 5) in par with females (n = 2) who were diagnosed with chronic apical periodontitis and/or repeated unsuccessful endodontic management. Diagnosis of root canal variation is important and different tools are employed in the reviewed studies [Table 1]. Advanced visual aids such as digital operating microscope, magnifying loupes with LED headlights are some of the noninvasive methods which offers magnified view and clear visualization of the pulpal floor. Recently, the addition of cone-beam computed tomography (CBCT) as a diagnostic tool has increased the accuracy of diagnosis to greater levels.

Cleaning and shaping of the canals in all the reviewed studies was efficaciously done with instrumentation using # 10, 15, 25, and 35 rotary files and the most commonly employed crown-down technique. The success rates of these reported cases were enhanced by the adequate irrigation done periodically with 2.5%–5% of NaOCl and/or 17% EDTA [Table 1] Cold lateral compaction or lateral compaction obturation techniques were effectively utilized along with AH26 sealer to achieve a three-dimensional apical seal. The success of endodontic management with atypical orifices was ascertained with a follow-up period which ranged between 1 week, 3 months, and 1 year. Improved magnifying tools, radiographs along with CBCT techniques enable proper assessment of anatomical variations of the root. As part of the successful endodontic outcomes.


Success of endodontic treatment is dependent on various factors. The type of tooth/ teeth involved, status of pulpal involvement, clinical and radiographic presentation, the canal preparation and the obturation efficiency are considered some of the proven determinants.[1],[33] Mandibular premolars are difficult teeth to treat because of morphological variations. Therefore, through this literature review with case report, we aimed to highlight that while treating such root anomalies, it is important to assess the tooth clinically as well as radiographically. Preoperative radiographs in different angles should be taken to ascertain the presence of any morphological variations, with particular focus on the existence of a third root.[34] According to Chalil et al. and Mokhtari et al., preoperative assessment could guide the proper access to the canal.[26],[27] In the cases reported by Fathi et al. and Lotfi et al., the efficient examination of the radiography and the tactile examination enabled the identification, negotiation, and provision of a successful endodontic seal of the teeth in focus.[28],[29] Confirmatory diagnosis with the help of the CBCT investigations has been reported in some of the case studies.[7],[27],[30] Proper visualization with optical and magnifying devices also aided in the precise location of the root canal orifices in spite of the anomalies. In the presented case report, the parallel technique radiography was used which enabled the detection of the unusual shape of the root and possibility of the third root.

According to Slowey, mandibular premolars, due to their complicated root canal anatomy, are the most difficult teeth for endodontic treatment.[16],[25],[35] Cleghorn et al. enumerated that 99.6% of mandibular second premolars had one root, while 0.3% of them had two roots and only around 0.1% of the study sample had three roots.[24],[36] Hence, a thorough understanding of the internal root anatomy of the affected teeth with radiographic interpretation was advocated by Chalil et al.[26]

Integrity of the tooth is often considered a crucial factor for the success of endo-treated teeth.[21] Earlier clinical studies have shown a direct relation between the longevity of the treated teeth and the preserved tooth structure.[2],[12],[37],[38] In the previous studies and case reports, various mechanisms, such as magnifier loupe, fiber-optic illumination, surgical operating microscope, use of dye/stain, and sodium hypochlorite bubbling, have been suggested to identify any morphological anomaly.[16],[27],[31],[32],[39] Similarly, in the presented case report, a surgical microscope (EXTARO 300 from ZEISS) was used for locating the third canal orifice. In addition, we utilized a hydraulic bonded obturation technique, for obturating all three canals, which resulted in the successful outcome.

Similar case reports have mentioned the challenges in the interventions in tooth with taurodontism due to voluminous and irregular pulpal spaces.[16],[19],[40],[41],[42] This was often overcome in most of the reviewed studies with proper instrumentation with combined use of sodium hypochlorite (2.5% or 5.25%) and 17% of EDTA irrigation.[34],[43] In the current case report, sodium hypochlorite along with EDTA was utilized as chemical irrigants to dissolve the necrotic tissue aiding complete debridement. The incidence of third roots in Saudi population is extremely low,[12],[44] yet this is the first male patient to be reported with three roots for second premolar tooth. Evidence-based clinical practice reiterates that, when such morphological variation is present, it is accompanied by some other tooth anomalies.[12],[38] For example, in this case, we noticed taurodontism that could have prevented the successful root canal treatment. Interestingly, the early detection of the taurodontism with the aid of the surgical microscope and proper obturation technique saved the tooth providing a proper apical and coronal seal. However, conventional radiographs depict a two-dimensional picture of a three-dimensional object, which usually results in superimposition of images. Therefore, their use and value are rather limited in complex root canal morphology cases. Interpretation based on conventional radiographs may alarm the clinician to the presence of unusual anatomy but usually cannot fully show the exact picture of canal morphology and their interrelations. The present report had the limitation of lack of advanced imaging modalities such as CBCT which could aid in efficient negotiation of the root orifices and their obturation. CBCT provides images of the root morphology with good spatial resolution, and hence ensure a long-term survival of the root canal treated with anomalies. This case report was prepared according to the PRICE 2020 Guidelines [Figure 6].[45]{Figure 6}


Clinicians must examine any tooth both clinically and radiographically before performing the endodontic treatment, specifically on those teeth which have noticeable morphological divergence. The use of surgical microscope and BioCeram materials helps to deliver right diagnosis and high-quality obturation in teeth with root canal variations and anomalies. Therefore, thorough examination with advanced technique before performing any procedure could modulate the treatment strategy and ensure the high success rates.


We would like to acknowledge the Postgraduate Department of Endodontics in Riyadh Elm University and the deanship of scientific research in Majmaah University.

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.


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