Importance of preoperative diagnostic imaging in treatment of maxillary central incisors with Vertucci's type V root canal configuration - A report of 2 cases.

Root canal system typically has a diverse canal configuration. One of the most difficult aspects of ensuring successful endodontic treatment is accurately identifying all canals found in a tooth. Diverse root canal configurations are not uncommon, even if the majority of maxillary incisors have a single root canal. One canal bifurcating into two at the apical third is exceptionally rare, with only two case reports previously reported. For the precise diagnosis of certain anatomical peculiarities, a thorough evaluation of preoperative diagnostic radiographs is highly required. As of periapical radiography, which is the most important diagnostic imaging for determining root canal anatomy, is limited by its two-dimensional nature, technological innovations such as cone beam computed tomography can be extremely beneficial. This paper emphasizes the significance of preoperative diagnostic imaging in the treatment planning of maxillary central incisors with unusual root canal morphology. Copyright:

INTRODUCTION

Root canal system usually presents with diverse canal configurations. To provide successful endodontic treatment in intricate canal configurations, a practitioner must have a detailed knowledge of the existing anatomy of the tooth. Harboring a reservoir of microorganism in the missed canals has been suggested to be the major cause of persistent apical periodontitis which has a direct impact on the treatment outcome.[1]

The accurate identification of all canals which present in a tooth is one of the most challenging aspects of providing suitable endodontic therapy. While root morphology has been extensively documented, the recognition of the root anatomy in a specific patient can still present a clinical challenge as there can be extensive disparities between patients. The incidence of an extra canal in the maxillary central incisor is 0.6%.[2] For the precise diagnosis of such anatomical peculiarities, careful inspection of preoperative diagnostic radiographs is very crucial.[3]

The major diagnostic imaging tool used to evaluate the root canal architecture and the severity of apical periodontitis is periapical radiographic imaging. Although substantial anatomical details suggesting additional roots or root canals are frequently well disclosed in their interpretation, radiographic imaging's two-dimensional nature limits the quantity of data collected.[4]

The application of cone beam computed tomography (CBCT) imaging for evaluating root canal architecture has been highly supported by the evidence since it offers information in all three planes.[5] The revised joint position statement on the use of CBCT, on the other hand, does not recommend its routine use in every individual, except when there is a suspicion of complex root canal architecture.[6] The usefulness of diagnostic imaging in finding extra canals in single-rooted teeth is emphasized in this case series.

CASE REPORT

Case 1

Twenty three-year-old female patient consulted our outpatient department for the severe pain in the upper front tooth region. The patient was healthy with no adverse medical conditions. The patient reported having undergone root canal treatment 1 month back. The percussion test showed a positive response on clinical examination. There was no sinus tract or mobility present. Probing depth was within normal limits. A single rooted 11 with one canal dividing into two at the apical third (Vertucci Type V configuration) was seen on a periapical radiograph (straight and mesial angulation). A well-defined periapical radiolucency measuring 2.4 mm × 1.2 mm was evident. A diagnosis was established for 11 as previously initiated therapy with symptomatic apical periodontitis. Multiple visit root canal treatment was planned. The patient was informed about the treatment's risks and benefits, And informed written consent was acquired. Under a dental operating microscope (DOM) (OPMI PICO; Carl Zeiss, Göttingen, Germany), the tooth was isolated and access opening was performed. Negotiation of canal bifurcation was achieved with a precurved #10 K-file (Dentsply Maillefer, Switzerland). The electronic apex locator (Root ZX small, J. Morita Co., Kyoto, Japan) was used to establish the working length, which was then verified by radiograph. Using a step-back approach, the canals were instrumented using hand files (Schilder 1974). Disinfection was achieved using 5.25% sodium hypochlorite followed by 17% ethylenediaminetetraacetic acid (Prevest DenPro Limited, Jammu, India). Calcium hydroxide dressing was placed for a week. At the second visit, after adequate disinfection, the canals were obturated by performing warm vertical compaction. A nanohybrid composite resin was used for permanent coronal sealing (Filtek Z250 XT, 3M ESPE, St. Paul, MN). Clinical examination at 12 months revealed no signs and symptoms and satisfactory radiographic healing of periapical tissues [Figure 1].

Figure 1

(a) Preoperative radiograph showing double periodontal ligament outline suggesting extra canal with periapical rarefaction, (b) Working length determination, (c) Completed root canal treatment (Vertucci Type V canal configuration), (d) Follow-up periapical radiograph showing complete periapical healing at 12 months

Case 2

A 57-year woman visited our clinic complaining of painful upper front tooth. A previous history of root canal treatment of the same tooth before 6 months was disclosed by the patient. The tooth 11 was discolored and was tender on percussion upon clinical evaluation. The coronal restoration was intact. Intraoral sinus tract was evident which was traced with gutta-percha radiographically. Periodontal examination revealed a probing depth of 7 mm buccally. No signs of mobility or swelling. Periapical radiography showed a root canal treated 11 which was well obturated without voids. Separated instrument fragment was evident on the additional canal, which splits from the main canal (Vertucci Type V configuration). Ill-defined periapical radiolucency of 4.7 mm × 5.4 mm with inflammatory apical root resorption of 11 was evident. CBCT scan was taken for presurgical assessment to understand the morphology of tooth better. Sagittal CBCT view revealed buccal perforation of the root at the level of Cemento-enamel junction (CEJ). Orthograde retreatment was performed following which periapical surgery was planned. A full-thickness mucoperiosteal flap was reflected after obtaining local anesthesia with 2% lidocaine and 1:80,000 epinephrine. After curetting the granulomatous tissue, cotton pellets dipped in 0.1% epinephrine were used to achieve hemostasis. The root end was inspected with the aid of DOM (OPMI PICO; Carl Zeiss, Göttingen, Germany, ftube = 170, flens = 250, meyepeiece = 12.5) at high magnification (×2.5). Both the apical openings of the canal were located. Separated instrument fragment was retrieved surgically by using ultrasonic tip. Both canal openings were retro prepared using ultrasonic retro tip (Satelec S12) to a depth of 3 mm and retrofilled with ProRoot MTA (Dentsply Tulsa specialties, USA). A resin-modified glass ionomer was used to restore the buccal perforation at the level of the CEJ. Flap was repositioned and sutured by using nonabsorbable 4-0 silk sutures. The patient was recalled after 4–5 days for suture removal. The patient was followed at 6 and 12 months. There was complete absence of signs and symptoms and satisfactory reduction in periapical radiolucency radiographically [Figure 2].

Figure 2

(a) Preoperative radiograph showing separated instrument fragment at canal bifurcation with periapical rarefaction, (b) Coronal view cone beam computed tomography, (c) Axial view at the level of canal bifurcation, (d) Sagittal cone beam computed tomography revealing buccal perforation at CEJ and apicomarginal defect in 11, (e) Orthograde retreatment, (f) Intraoperative picture after flap reflection, (g) Surgical retrieval of separated instrument and retro preparation of both canals, (h) Intraoperative photograph showing repair of the perforation site with resin-modified glass ionomer, (i) Immediate postsurgical radiograph, (j) One-year follow-up radiograph showing satisfactory healing

DISCUSSION

The aim of this paper was to highlight the importance of preoperative diagnostic imaging in the treatment of maxillary central incisors with Vertucci type V configuration. Clearing studies and individual case reports serve as the basis for existing knowledge of root canal anatomy. Many clinicians presume that there are predefined canals in a particular tooth. However, deviation from normal anatomy is not uncommon. Maxillary incisors typically have a single root canal that is housed in a single root.[7] Previous studies have documented anatomical variations, i.e., presence of single-root with two canals,[89] or double-rooted teeth[1011] up to three canals[12] usually coexist with developmental anomalies such as gemination, fusion, or dens invaginatus.[13] The most common variation in all these recorded cases was Vertucci type IV (2-2). Others variations such as Type II (2-1) and Type III (1-2-1) have also been reported. The occurrence of Vertucci Type V is very rare and was reported by only two case reports[1415] until recently, both of them were nonsurgically managed. This article presents 2 cases with Vertucci Type V configuration without morphological anomaly which was managed by both surgical and nonsurgical approach. Surgery was chosen for case 2 as orthograde retreatment was not feasible due to separated instrument fragment in lateral canal.

Since success of endodontic treatment is reliant on the comprehensive root canal debridement, knowledge of extra and intracanal anatomical variations is essential. This understanding requires the identification of anatomical landmarks before and during the treatment procedure associated with normal and aberrant anatomy observed in everyday practice.[3] Diagnostically acceptable periapical radiographs at more than two views (90° and 10° mesial or distal projection) provide precise description of root canal bifurcations and lamina dura. When traditional radiographs lack adequate information, novel diagnostic modality such as CBCT can be useful, particularly when canals are located buccopalatally.[4] In the present case report, CBCT scan was taken for case 2 to provide additional relevant details regarding canal anatomy and location of separated instrument.

In endodontics, CBCT imaging demands extremely high detail and resolution to understand the intricacies of the root canal and periodontium. However, high image resolution comes at the expense of greater patient radiation. Limited field of view scan is generally recommended for endodontic problems as it decreases the amount of tissue exposed.[56]

Although complex canal configuration poses a serious endodontic challenge, visualization of pulp chamber under DOM or loupes and exploration of pulp chamber helps in decreasing risk of iatrogenic errors and increases the likelihood of discovering extra canals.[16] It is important to carefully extend the access opening, particularly over the lingual shoulder, to uncover any additional canals.

CONCLUSION

While most studies indicate that the presence of single canal in maxillary central incisor, dentists must therefore cautiously perform the endodontic treatment with an unbiased view and anticipate morphological differences in every case encountered. A comprehensive preoperative diagnostic imaging, such as CBCT, and enhanced visualization are needed in effective endodontic treatment of single-rooted teeth with intricate root canal architecture.

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

Nil.

Conflicts of interest

There are no conflicts of interest.