Anatomical variations in root or root canal anatomy pose a great endodontic challenge to the most experienced clinicians. Anatomical studies have shown that permanent maxillary lateral incisors usually have only one root, with 100% of them having single canal anatomy [1] [2] [3] [4]. More than one canal in maxillary lateral incisors is not a very common finding [5] [6] [7]. Literature search revealed very few reports of two canalled maxillary lateral incisors. The aim of the present article is to describe a maxillary lateral incisor with two root canals that was diagnosed during radiographic examination of other teeth.

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Figure 1. Fractured and root canal treated maxillary left central incisor (arrow)

A 10-year-old male patient complained of unaesthetic appearance of fractured tooth in the upper front region. There was a history of trauma to the upper anterior teeth, one year back due to fall. Patient’s past dental history revealed root canal treatment of the upper left permanent central incisor in a private dental clinic (Fig. 1). Radiographic survey showed radiopaque obturating material in canal space of the same tooth (Fig. 2). On careful reading of the radiograph the right lateral incisor exhibited unusual canal morphology. Two thin radiolucent lines appeared running from the pulp chamber extending up to the apical third and just short of the apex they joined leading to one line (Fig. 2). These lines were diagnosed as two canals and classified as type II (2-1) according to Vertucci’s canal classification [1] (Table 1). The corresponding tooth on the opposite side of the arch showed single canal. As the two canaled right lateral incisor was not affected with any pathology no other treatment was required in this case.

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Figure 2. Maxillary lateral incisor showing two canals (arrows)

Maxillary lateral incisors are subjected to high embryological risk and thus subjected to developmental variations. Several developmental anomalies have been found in these teeth like the presence of two roots as a result of fusion/germination, dens invaginatus, radicular lingual groove (RLG), talon cusp and peg shape [8] [9] [10]. Some studies have shown displacement of the root apex and apical foramen [11]. Various case reports and studies demonstrated significant variability in canal anatomy of maxillary lateral incisor and they are summarized in Table 2 [5] [6] [7] [16] [17] [18] [19] [20] [21] [22] [1]. Description of multiple canals in these teeth is limited to case reports [15] [19]. Therefore root canal treatment is not always expected easy in lateral incisors. Endodontic mishaps are more likely to happen with a missed canal that was not negotiated during root canal treatment. Peikoff and Trott [10] presented an endodontic failure in a maxillary lateral incisor with an accessory root and radicular groove.

Clinicians must be familiar with the various pathways the root canals take to the apex. The pulp canal system is complex, and canals may branch, divide, and rejoin. Vertucci et al. [1], using cleared teeth in which the root canal systems had been stained with hemotoxylin dye, found a much more complex canal system; they identified eight pulp space configurations, which is represented in Table 1.

In our case, lateral incisor had a single root with two separate canals joining into one canal just short of the apex. This belonged to Vertucci’s type II root canal anatomy (2-1) (Table 1). Ghoddusi [22] reported endodontic treatment of maxillary lateral incisor with two canals which was type II of canal classification. Altuntas et al. [21] carried out successful treatment for the immature maxillary lateral incisor having two canals. Apical closure was evident after 1 year follow-up in their case.

The present case report suggests the need for careful attention when reading the radiographs and also the need for developing good quality radiographs taken in different angulations during diagnosis. This is very essential at various stages of endodontic therapy and their thorough evaluation to prevent mishaps. In addition to standardized radiographs, use of computerized digital radiography, cone-beam computed tomography, and high-resolution magnification will increase the ability to clinically determine the presence of additional canals and in turn to prevent treatment failures.