| Abstract|| |
This case report describes endodontic treatment completed in a peg-shaped maxillary lateral incisor, with single root and five root canals of which, one is due to dens invaginatus. Cone beam computed tomogram scanning confirmed the unique morphology of the tooth. New nomenclature for the five canals is proposed.
Keywords: Cone beam computed tomogram; five root canals; maxillary lateral incisor
|How to cite this article:|
Jaikailash S, Kavitha M, Ranjani MS, Saravanan B. Five root canals in peg lateral incisor with dens invaginatus: A case report with new nomenclature for the five canals. J Conserv Dent 2014;17:379-81
|How to cite this URL:|
Jaikailash S, Kavitha M, Ranjani MS, Saravanan B. Five root canals in peg lateral incisor with dens invaginatus: A case report with new nomenclature for the five canals. J Conserv Dent [serial online] 2014 [cited 2020 Aug 8];17:379-81. Available from: http://www.jcd.org.in/text.asp?2014/17/4/379/136516
| Introduction|| |
Success in endodontic treatment is best defined by the contemporary endodontic triad of diagnosis, anatomy, and debridement.  In the learning curve of endodontics, the incisor tooth forms the basics due to its simple morphology of one root-one canal.  The common developmental anomalies in a maxillary lateral incisor (MLI) includes peg-shaped crown, radicular groove, talon cusp, and dens invaginatus (DI).  From an endodontic perspective additional canals than the normally expected is considered as an anomaly. 
Considering the occurrence of additional canals, the literature shows that, MLI with a maximum of four canals  and with dens formation, three root canals  have been reported. Zillich et al. have reported MLI with two roots and dens formation. 
Teeth with DI are often recognized clinically due to their unusual crown form or extremely marked foramen caecum  and many a time may show no clinical signs of the malformation.  Thus, a thorough clinical and radiological examination is imperative. However, due to the limitation of conventional radiographs in assessing root canal configuration, complex root canal morphology due to dental anomalies such as multiple root canals, two roots and dens formation poses a considerable diagnostic challenge to achieve the required success. , Nevertheless, advanced radiographic techniques such as the cone beam computed tomogram (CBCT) helps in a three-dimensional evaluation of a particular tooth to overcome the limitations of conventional radiography. ,
The purpose of the present case report is to discuss the endodontic procedure adopted to negotiate the complex tooth morphology of a peg-shaped MLI with DI and five root canals (FRC).
| Case report|| |
The present case is about a 17-year-old male patient who was referred to the Department of Endodontics with a primary complaint of heaviness and pain in relation to the upper front tooth. There was no preceding history of trauma or similar episodes of heaviness and pain.
Clinical evaluation revealed no significant extraoral findings. On intraoral examination, both the MLIs appeared peg-shaped. However, the right lateral incisor was associated with a soft tissue swelling in the labial vestibule [Figure 1]a], tender on percussion and gave a negative response to electric pulp testing. Intra oral periapical radiograph of the maxillary right lateral incisor revealed ill-defined periapical radiolucency associated with an unusual canal morphology and DI [Figure 1]b]. Based on the clinical and radiological findings, a diagnosis of acute periapical abscess was made.
|Figure 1: (a) Peg-shaped lateral incisor with intra-oral swelling in the labial vestibule. (b) Radiograph revealing|
periapical radiolucency associated with right lateral incisor and presence of dens invaginatus. (c) Canal orifi ce location and nomenclature. (d) Radiograph with instruments in fi ve canals
Click here to view
The need for an endodontic therapy was explained to the patient and was advised to take a course of analgesics and antibiotics (amoxicillin 500 mg, metronidazole 400 mg, ibuprofen 400 mg thrice daily for 5 days). The patient was administered local anesthesia of 2% lidocaine with 1:100,000 epinephrine. Under rubber dam isolation, an access opening was made and an orifice (C1) was visualized after copious amount of purulent discharge was allowed to drain through the C1. The endodontic explorer was placed in the C1 and verified with an apex locator (Sybron Endo Mini, Sybron Endo, Glendora, USA) and radiograph. It was found in the canal space corresponding to the DI. However, as the drainage of purulent discharge persisted, a calcium hydroxide intra-canal medicament (Calcicur, VOCO, Cuxhaven, Germany) was placed and access cavity was temporarily sealed. (Cavit, 3M ESPE AG, Seefold, Germany).
After 3 days, the calcium hydroxide was removed from C1 and subtle changes were noted at some points over the sub-pulpal floor, which suggested the possibility of additional canals away from the C1 that was located on the labial half. In order to locate the possibility of a palatal canal, the access cavity was redefined in the distopalatal (DP) region and the second canal (C2) was identified and negotiated successfully. On further probing in the distolabial (DL) region, two additional orifices (C3 and C4) were noted labial to (C2). However, the orifices of C3 and C4 were interconnected. With four instruments placed in the respective canals, the radiograph showed the presence of another unidentified canal. The fifth canal orifice (C5) was located at the mesiopalatal (MP) aspect, summing-up to five canals all with separate apical exit [Figure 1]c and d]. Each time an orifice was identified, it was checked with an apex locator to rule out perforation.
Coronal flaring alone was performed with ProTaper rotary Ni Ti instruments (Dentsply, Maillefer) and subsequent cleaning and shaping was completed by hand instrumentation (Dentsply, Maillefer) due to the constricted coronal pulp space. The apical enlargement of all canals was maintained at size 25 ISO. Intra-canal calcium hydroxide medication was placed and access cavity was temporarily sealed.
A CBCT scanning was done to study the tooth morphology, which confirmed the presence of a single root with five canals with separate apical exit and a type III DI [Figure 2]a and b].
|Figure 2: (a) cone beam computed tomogram (CBCT)– sagittal view. (b) CBCT– axial view. (c) Radiograph taken after root canal fi lling and placement of temporary restoration in the access cavity. (d) Follow-up radiograph after 12 months showing signs of healing|
Click here to view
One week later the tooth was obturated in the third visit, with Gutta-percha and sealer (Apexit, Ivoclar Vivadent) by cold lateral compaction technique [Figure 2]c]. The patient was periodically monitored, with satisfactory healing and the follow-up period of 12 months was uneventful [Figure 2]d].
| Discussion|| |
Dens invaginatus is a developmental malformation resulting from invagination of the crown or root before calcification has occurred.  With a reported incidence from 0.04% to 10%, DI can be found affecting either the primary  or the permanent dentition,  and commonly involving the MLIs.  Cases of bilateral occurrence ,, and rare cases are reported in molars,  premolars,  and maxillary central incisors.  An Indian study reported a prevalence of 0.5% of surveyed teeth;  however, according to a Chinese study, DI was found in 517 permanent teeth from 67 Chinese individuals, which account for 5% of DI. These authors believe that the prevalence of DI may be related to ethnic origin. 
The literature shows that MLI with a maximum of four canals has been reported,  but as far as the author's knowledge, this is the first case with FRC, especially in a peg-shaped lateral incisor complicated by the presence of DI. According to the literature, DI in a MLI is considered as unusual. DI is classified into three types. Type 1 is an invagination confined to the crown. Type 2 involves the root, but does not reach the apex, and in Type 3, the invagination extends past the periapical region with and without manifesting an additional apical foramen. 
The pathways of infection in a DI is found to be due to hypomineralized internal enamel and the thin canals or fissures in the dentin connecting the invagination to the pulp cavity through which microorganisms and irritating agents from the oral cavity gain access to the pulpal space leading to pulp alterations. 
The challenge posed in this case is the restricted access coupled with complex and unpredictable morphology of the root canal system. Krapež and Fidler emphasized the need and suggested incisal edge as the predominant location of straight-line access in anterior teeth.  Various treatment techniques have been reported in the literature, including preventive sealing or filling of the invagination, root canal treatment with or without endodontic apical surgery, intentional replantation and extraction. ,, Removal of DI using hand files and Gates Glidden drills  and with the aid of an operating microscope and subsequent root canal treatment has also been described. 
The presence of multiple root canals in a peg-shaped MLI complicated by DI poses substantial difficulty in diagnosis and treatment as well as achieving endodontic success for better prognosis. The present case has been evaluated and negotiated with the aid of conventional radiographs and by applying law of symmetry, cemento enamel junction and orifice location.  The complicated tooth morphology with multiple root canals warrant use of CBCT to define and confirm the canal morphology. In line with a molar tooth, the multiple canals in this case is named according to the surface in which it is located namely C1 - mesiolabial, C2 - DP, C3 and C4 - DL1 and DL2, and C5 - MP, respectively [Figure 1]c].
| Conclusion|| |
Case selection is the key in successful outcome of a treatment. Treating a tooth with a unique morphology definitely tests the clinical knowledge, skill of the operator and one should be ready for any kind of pulp space variant that could exist. Although, CBCT would have been beneficial to precisely define and confirm the canal location in a complicated morphology, the present case illustrates the successful negotiation with conventional radiographs.
| References|| |
|1.||Gutmann JL, Dumsha TC, Lovdahl PE, Hovland EJ. Problem Solving in Endodontics. 3 rd ed. St. Louis: Mosby; 1997. p. 1-21. |
|2.||Hargreaves KM, Cohen S, Berman LH. Pathways of the Pulp. 10 th ed. St. Louis, Missouri: Elsevier Mosby; 2011. p. 136-219. |
|3.||Ingle JI, Bakland LK, Baumgartner JC. Endodontics. 6 th ed. Hamilton: BC Decker Inc.; 2008. p. 151-210. |
|4.||Kottoor J, Murugesan R, Albuquerque DV. A maxillary lateral incisor with four root canals. Int Endod J 2012;45:393-7. |
|5.||Walvekar SV, Behbehani JM. Three root canals and dens formation in a maxillary lateral incisor: A case report. J Endod 1997;23:185-6. |
|6.||Zillich RM, Ash JL, Corcoran JF. Maxillary lateral incisor with two roots and dens formation: A case report. J Endod 1983;9:143-4. |
|7.||Hülsmann M, Hengen G. Severe dens invaginatus malformation: Report of two cases. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1996;82:456-8. |
|8.||Gonçalves A, Gonçalves M, Oliveira DP, Gonçalves N. Dens invaginatus type III: Report of a case and 10-year radiographic follow-up. Int Endod J 2002;35:873-9. |
|9.||Matherne RP, Angelopoulos C, Kulild JC, Tira D. Use of cone-beam computed tomography to identify root canal systems in vitro. J Endod 2008;34:87-9. |
|10.||Tyndall DA, Rathore S. Cone-beam CT diagnostic applications: Caries, periodontal bone assessment, and endodontic applications. Dent Clin North Am 2008;52:825-41, vii. |
|11.||Hülsmann M. Dens invaginatus: Aetiology, classification, prevalence, diagnosis, and treatment considerations. Int Endod J 1997;30:79-90. |
|12.||Mupparapu M, Singer SR. A review of dens invaginatus (dens in dente) in permanent and primary teeth: Report of a case in a microdontic maxillary lateral incisor. Quintessence Int 2006;37:125-9. |
|13.||Bimstein E, Shteyer A. Dilated type of dens invaginatus in the permanent dentition: Report of a case and review of the literature. ASDC J Dent Child 1976;43:410-3. |
|14.||Caldari M, Monaco C, Ciocca L, Scotti R. Single-session treatment of a major complication of dens invaginatus: A case report. Quintessence Int 2006;37:337-43. |
|15.||Swanson WF, McCarthy FM Jr. Bilateral dens in dente. J Dent Res 1947;26:167-71. |
|16.||Burton DJ, Saffos RO, Scheffer RB. Multiple bilateral dens in dente as a factor in the etiology of multiple periapical lesions. Oral Surg Oral Med Oral Pathol 1980;49:496-9. |
|17.||Canger EM, Kayipmaz S, Celenk P. Bilateral dens invaginatus in the mandibular premolar region. Indian J Dent Res 2009;20:238-40. |
|18.||Costa WF, Sousa Neto MD, Pécora JD. Upper molar dens in dente - Case report. Braz Dent J 1990;1:45-9. |
|19.||Girsch WJ, McClammy TV. Microscopic removal of dens invaginatus. J Endod 2002;28:336-9. |
|20.||Vasudev SK, Goel BR. Endodontic management of dens evaginatus of maxillary central incisors: A rare case report. J Endod 2005;31:67-70. |
|21.||Patil S, Doni B, Kaswan S, Rahman F. Prevalence of dental anomalies in Indian population. J Clin Exp Dent 2013;5:e183-6. |
|22.||Shi S, Duan X, Shao J, Duan Q, Peng S. Dens invaginatus in ancient Chinese teeth of 2,000 years ago. Anat Rec (Hoboken) 2013;296:1628-33. |
|23.||Beynon AD. Developing dens invaginatus (dens in dente). A quantitative microradiographic study and a reconsideration of the histogenesis of this condition. Br Dent J 1982;153:255-60. |
|24.||Krapež J, Fidler A. Location and dimensions of access cavity in permanent incisors, canines, and premolars. J Conserv Dent 2013;16:404-7. |
|25.||Hata G, Toda T. Treatment of dens invaginatus by endodontic therapy, apicocurettage, and retrofilling. J Endod 1987;13:469-72. |
|26.||De Smit A, Demaut L. Nonsurgical endodontic treatment of invaginated teeth. J Endod 1982;8:506-11. |
|27.||Sigrist De Martin A, da Silveira Bueno CE, Sandhes Cunha R, Aranha de Araújo R, Fernandes de Magalhães Silveira C. Endodontic treatment of dens invaginatus with a periradicular lesion: Case report. Aust Endod J 2005;31:123-5. |
|28.||Rajini MA, Kalwar A, Meena N, Kumar RA, Shetty A, Naveen DN, et al. Nonsurgical endodontic treatment of type II dens invaginatus. J Conserv Dent 2009;12:73-6. |
|29.||Krasner P, Rankow HJ. Anatomy of the pulp-chamber floor. J Endod 2004;30:5-16. |
Department of Conservative Dentistry and Endodontics, Tamil Nadu Government Dental College and Hospital, Chennai, Tamil Nadu
Source of Support: None, Conflict of Interest: None
[Figure 1], [Figure 2]