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Year : 2014  |  Volume : 4  |  Issue : 1  |  Page : 28-31

Endodontic management of a supernumerary tooth fused to the maxillary permanent lateral Incisor

Department of Conservative Dentistry and Endodontics, K.L.E.V.K. Institute of Dental Sciences, Belgaum, Karnataka, India

Date of Web Publication28-Feb-2014

Correspondence Address:
Avinash A Patil
A-14/10, Staff Quarters, J.N.M.C. Campus, Nehru Nagar, Belgaum, Karnataka
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/1658-5984.127984

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The aim of this case report is to present the endodontic management of a supernumerary tooth fused to the maxillary left lateral incisor. Such anomalies pose a challenge even to the most experienced clinician in treating these teeth. This report described a case of 21-year-old male patient with a classic case of complete fusion of maxillary left lateral incisor and a supernumerary tooth. A modified access preparation was made and two separate root canal orifices were identified. Both root canal systems were prepared separately and obturated efficiently until accepted lengths. This reported case highlights the importance of clinical and radiographic correlation in arriving to a definitive diagnosis.

Keywords: Developmental anomaly, esthetics, fusion, gemination, supernumerary tooth

How to cite this article:
Patil AA, Patil SA, Dodwad PK. Endodontic management of a supernumerary tooth fused to the maxillary permanent lateral Incisor. Saudi Endod J 2014;4:28-31

How to cite this URL:
Patil AA, Patil SA, Dodwad PK. Endodontic management of a supernumerary tooth fused to the maxillary permanent lateral Incisor. Saudi Endod J [serial online] 2014 [cited 2023 Mar 22];4:28-31. Available from: https://www.saudiendodj.com/text.asp?2014/4/1/28/127984

  Introduction Top

Odontogenic anomalies can be encountered in dental practice and are often a great challenge to the dentist. One such dental anomaly is fusion (fusio dentes, dentes confusi, synodonthia). [1] Pindborg defined fusion as the union between dentin and/or enamel of two or more separate developing teeth. [2] Shafer et al. theorized that fusion is the result of specific pressure or physical force that results in direct contact in the development of two dental germs. This intimate pressure causes necrosis of the intercellular tissues, allowing the close union of these two dental organs. [3] Conversely, spouge stated that this union is purely casual. [4] Other investigators have confirmed heredity as a contributing factor. [5],[6]

A similar odontogenic developmental anomaly is gemination which is often difficult to differentiate clinically from fusion. Pindborg described gemination as the malformation of a single tooth bud, resulting in an anomalous tooth within the normal complement of teeth. It is recognized as an attempt by a single tooth germ to divide, with a resultant large single tooth with a bifid crown and usually a common root and root canal. [2]

In cases of fusion, the crowns are united by enamel and/or dentin and there are two roots or two root canals in a single root and if the fused tooth is counted as 1 unit, there will be one tooth less in the arch than normal. In contrast, in gemination, the structure most often presents two crowns, either totally or partially separated, with a single root and one root canal and if the anomalous tooth is counted as 1 unit, the number of teeth in the arch will be normal. Gemination may be differentiated from fusion by the increased number of teeth, except in unusual cases, in which the fusion is between a supernumerary tooth and a normal tooth. [7] The clinician must then depend on both clinical examination and radiographs to make the final diagnosis between fusion and gemination.

These types of anomalies may be unilateral or bilateral and may affect either dentition, although the primary teeth are more commonly affected. The incidence of this anomaly is 0.5% in the primary dentition and 0.1% in the permanent dentition. [8] Fusion of permanent and supernumerary teeth occurs less frequently than fusion between permanent teeth. Hachisuka reported that the frequency of fusion between permanent and supernumerary teeth is 0.1% and that this type of fusion usually involves maxillary anterior teeth. [9]

This case report describes the endodontic management of a supernumerary tooth fused to the left maxillary lateral incisor. Though there are several cases reported in the dental literature of fusion; very few cases have been reported in which a supernumerary tooth was fused to the maxillary lateral incisor; thus making it a rare anatomic variant.

  Case Report Top

A 21-year-old male patient without remarkable medical history, presented to the Department of Conservative Dentistry and Endodontics, with the chief complains of spontaneous pain in the left maxillary anterior region of the jaw since 1 month. Clinical intraoral examination revealed localized macrodontia associated with the left maxillary lateral incisor with deep carious lesion. Tooth count was normal. Periapical radiograph revealed radiolucency in the crown portion involving the pulp. The tooth was painful on percussion and gave exaggerated responses to thermal and electric pulp tests. After clinical and radiographic examination, a diagnosis of chronic irreversible pulpitis with apical periodontitis was made and the patient was prepared for root canal treatment.

Patient received local anesthesia of 2% lidocaine. After removing the caries, an ideal triangular access opening was made under aseptic conditions . After cervical flaring with Protaper Universal Shaping files S1 and SX (Dentsply, Maillefer), working length was estimated by means of an apex locator (Dentaport ZX, J Morita Corp.) and confirmed with intraoral periapical radiograph. Biomechanical preparation was performed using the crown-down technique with Protaper Universal (Dentsply, Maillefer) rotary NiTi files along with copious irrigation with 3% sodium hypochlorite (Vishal Dentocare Pvt. Ltd., Ahmedabad, Gujarat, India). A radiograph was taken with master cone in place to reconfirm working length [Figure 1].
Figure 1: Radiograph after master cone placement suggesting the possibility of additional canal

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In this radiograph, an unusual finding was made. It was observed that master cone was not centered within the root and the root seemed to have another root apex. This eccentric position of the master cone implied the presence of an additional canal. Careful clinical observation of the tooth revealed an indentation on the labial surface running from the incisal edge to the cervical margin almost dividing the crown into two halves. Prominent bifid cingulum with a central cervico-incisal groove and deep pits were seen on the palatal surface. These findings suggested that it could be a case of fusion.

Now the access was expanded and modified to trapezoidal shape so as to enhance vision and improve diagnostics. This modification revealed another orifice distal to the previous orifice. On clinical examination, two separate root canal orifices were identified. A #10 K-file was inserted into this orifice and ruled out for perforation using apex locator (Dentaport ZX, J Morita Corp, Kyoto, Japan). It was confirmed to be an additional canal [Figure 2]. Another angled radiograph was taken that revealed a single large root with two separate root canals. Therefore, it was ascertained that it was a case of complete fusion. Since the tooth count was normal, it was a fusion of supernumerary tooth to the left maxillary lateral incisor.
Figure 2: Clinical photo of chamber floor showing two root canal orifices

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Final irrigation was done with 3% sodium hypochlorite followed by a rinse with normal saline. The canals were dried with paper points and obturated with gutta-percha and AH Plus sealer (Dentsply, Maillefer) using lateral condensation technique. Post-treatment radiograph revealed two independent root canals within the single root, obturated efficiently with gutta-percha to the accepted lengths [Figure 3]. The access was temporarily restored with Cavit-G and the patient was recalled after a week.
Figure 3: Final radiograph after root canal therapy

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Patient was not willing for crown and any esthetic corrections with the same tooth. Furthermore, since the tooth was still structurally strong enough due to enough tooth structure present, it was decided to permanently restore the access cavity by use of conservative restoration like composite after proper shade matching using shade A2 (Filtek Z 350, 3M ESPE).

At 1-year follow-up radiograph revealed the integrity of the root canal therapy and a normal periapex [Figure 4]. Patient was completely asymptomatic.
Figure 4: One year follow-up radiograph

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  Discussion Top

The degree of fusion depends upon the stage of tooth development that has occurred at the time of fusion, with the union of dentin being the main criterion. Fused teeth may contain separate pulp canals or share a common pulp canal. Fusion may occur between two normal teeth or between a normal tooth and a supernumerary tooth. [10] They may be associated with syndromes such as Wolf-Hirschhorn syndrome, achondroplasia, focal dermal hypoplasia, osteopetrosis, and chondroectodermal dysplasia; or they can be found in non-syndromic patients as well. [11] In this reported case, a supernumerary tooth was fused to the maxillary permanent lateral incisor. The frequency of supernumerary teeth was found in the maxilla 8.2-10 times more than the mandible. [12],[13]

The presence of fused teeth may lead to orthodontic problems, such as spacing or crowding of teeth, loss of arch length, esthetic problems, increased caries risk, and deviation of the midline. [14] Management of such a problem might involve root canal treatment.

Since grooves created by the union between the teeth involved are deep and extend subgingivally, bacterial plaque accumulates readily in this area. While pulpal involvement of these teeth is common, endodontic treatment is usually problematic due to complex anatomy, tooth position and difficulty in rubber dam isolation. [3]

Detection of additional canals requires a careful clinical and radiographic inspection. Diagnostic tools such as multiple radiographs, careful examination of the pulpal floor with a sharp explorer and better visualization using an operating microscope are all important aids in the detection of additional root canals. Recently, various attempts have been made to use computed tomography imaging for the confirmatory diagnosis of morphologic aberrations in the endodontic field. [15]

In the case presented, after identifying the unusual canal configuration with the help of angled radiograph and forming a treatment plan, it was not difficult to treat this tooth endodontically. The ensuing result was positive and satisfactory.

  Conclusion Top

Treating additional aberrant canals can be challenging, but the inability to find root canals may cause failures. [11] Although such cases occur infrequently, these canal systems do exist and alert the dentist to proceed with a thorough examination of the pulp chamber floor even after the expected number of canals have been identified. The use of operating microscope can enable the clinician to investigate the root canal system and to clean, shape and obturate it more efficiently.

  References Top

1.Neville BW, Damm DD, Allen CM, Bouquot JE. Abnormalities of teeth. Oral and Maxillofacial Pathology. 2 nd ed. Philadelphia, PA: WB Saunders; 2002. p. 74-5.  Back to cited text no. 1
2.Pindborg JJ. Pathology of the Dental Hard Tissues. Philadelphia: W.B. Saunders; 1970.  Back to cited text no. 2
3.Shafer W, Hine M, Levy B. A Textbook of Oral Pathology. 4 th ed. Philadelphia: W.B. Saunders; 1983. p. 20-80.  Back to cited text no. 3
4.Spouge JD. Oral Pathology. St Louis: Mosby; 1973. p. 125-44.  Back to cited text no. 4
5.Levitas TC. Gemination, fusion, twinning and concrescence. ASDC J Dent Child 1965;32:93-100.  Back to cited text no. 5
6.O'Reilly PM. A structural and ultrastructural study of a fused tooth. J Endod 1989;15:442-6.  Back to cited text no. 6
7.Tannenbaum KA, Alling EE. Anomalous tooth development. Case reports of gemination and twinning. Oral Surg Oral Med Oral Pathol 1963;16:883-7.  Back to cited text no. 7
8.Kelly JR. Gemination, fusion, or both? Oral Surg Oral Med Oral Pathol 1978;45:326-7.  Back to cited text no. 8
9.Yuzawa M, Akimoto Y, Omata H, Nakamura T, Kaneko K, Yamamoto H. Fusion of a maxillary central incisor with a supernumerary tooth. J Nihon Univ Sch Dent 1985;27:252-4.  Back to cited text no. 9
10.Ballal NV, Kundabala M, Acharya S. Esthetic management of fused carious teeth: A case report. J Esthet Restor Dent 2006;18:13-7.  Back to cited text no. 10
11.Schuurs AH, van Loveren C. Double teeth: Review of the literature. ASDC J Dent Child 2000;67:313-25.  Back to cited text no. 11
12.Yusof WZ. Non-syndrome multiple supernumerary teeth: Literature review. J Can Dent Assoc 1990;56:147-9.  Back to cited text no. 12
13.Açikgöz A, Açikgöz G, Tunga U, Otan F. Characteristics and prevalence of non-syndrome multiple supernumerary teeth: A retrospective study. Dentomaxillofac Radiol 2006;35:185-90.  Back to cited text no. 13
14.Yuen SW, Chan JC, Wei SH. Double primary teeth and their relationship with the permanent successors: A radiographic study of 376 cases. Pediatr Dent 1987;9:42-8.  Back to cited text no. 14
15.Sponchiado EC Jr, Ismail HA, Braga MR, de Carvalho FK, Simões CA. Maxillary central incisor with two root canals: A case report. J Endod 2006;32:1002-4.  Back to cited text no. 15


  [Figure 1], [Figure 2], [Figure 3], [Figure 4]

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