Case Report/Clinical Techniques
Unilateral Fusion of a Supernumerary Tooth to a Maxillary Permanent Lateral Incisor: A Report of a Rare Case Rodrigo Sanches Cunha, DDS, MSc, PhD, FRCD(C),* Alanna Junaid, BSc DMD BSc (Dent),* and Isabel Mello, DDS, MSc, PhD, FRCD(C)*† Abstract A supernumerary tooth is an additional entity to the normal series of teeth that may occur in isolation or may be fused to a normal counterpart. Diagnosis and delineation of an accurate treatment plan in cases involving supernumerary teeth are often a challenge. This report describes a case of unilateral fusion of a supernumerary tooth to a maxillary permanent lateral incisor in which a conservative approach was used to reach a favorable outcome. (J Endod 2015;41:420–423)
Key Words Anatomy, CBCT, fusion, supernumerary
From the *Division of Endodontics, University of Manitoba, Winnipeg, Manitoba, Canada; and †Division of Endodontics, Dalhousie University, Halifax, Nova Scotia, Canada. Address requests for reprints to Dr Rodrigo Sanches Cunha, Department of Restorative Dentistry, Endodontology, University of Manitoba D226C, 780 Bannatyne Avenue, Winnipeg, MB, Canada R3E 0W2. E-mail address: rodrigo.odonto@ hotmail.com 0099-2399/$ - see front matter Copyright ª 2015 American Association of Endodontists. http://dx.doi.org/10.1016/j.joen.2014.10.021
A
supernumerary tooth is an additional entity to the normal series of teeth and may be seen in any quadrant of the jaws. These teeth may have a normal morphology, or they may be rudimentary and miniature. Supernumerary teeth are much more commonly seen in the maxilla than in the mandible (10 to 1) (1). Tooth fusion results from the union of 2 or more tooth germs during the developmental process and may occur between both the dentin and enamel layers, or it may involve just the enamel layer (2). Both the epithelial and mesenchymal germ layers are involved, which leads to irregularities in tooth morphology (3). In fused teeth the root canal systems may be connected or completely separate, depending on the developmental stage at which the union took place (2). The incidence of fusion is approximately 0.1% in the permanent dentition and 0.5% in the primary dentition in the white population (4). Fusion between supernumerary and permanent teeth occurs less frequently than fusion between other types of teeth (5). Clinically, several complications may occur because of the fusion of teeth such as the development of caries in the groove between the fused crowns, tooth impaction, diastemas, aesthetic and periodontal problems, and pulpal pathosis. Many of these complications demand a multidisciplinary approach, and treatment depends on the type and position of the supernumerary tooth and on its relation to the adjacent teeth (5–8). If incomplete fusion is present and there is no communication of the root canal systems, nonsurgical root canal treatment may be rendered on the affected tooth only, preserving the vitality of the unaffected counterpart. A thorough diagnosis is paramount to the formulation of an accurate treatment plan that will lead to a favorable prognosis. In endodontics, periapical radiographs are mandatory for diagnosis, treatment, and follow-up. However, they provide a limited 2-dimensional view of the true 3-dimensional (3D) anatomy. With the advent of cone-beam computed tomography (CBCT), accurate 3D imaging of teeth and their surrounding dentoalveolar structures is now readily obtainable (9). Because of shorter acquisition times and significant reductions in radiation exposure as compared with conventional CT imaging, CBCT scans are ordered with increasing frequency. The ability to accurately focus on specific regions by using a small field of view further avoids unnecessary radiation exposure and provides a minimally invasive approach to acquiring detailed diagnostic information (10). This report describes a case of unilateral fusion of a supernumerary tooth to a maxillary permanent lateral incisor in which a conservative approach was used to reach a favorable outcome.
Case Report A 20-year-old female white patient was referred to an endodontist for assessment and necessary treatment of her maxillary right lateral incisor (tooth #7). Her chief complaint was of spontaneous pain that necessitated 400 mg ibuprofen be taken every 8 hours for relief. Her medical status was noncontributory. At this stage, the patient had been evaluated by both a periodontist and an oral and maxillofacial surgeon. Collaboratively, they had suggested that the supernumerary tooth lingual to tooth #7 be surgically extracted and that the resultant defect be bone grafted to prevent the development of future periodontal problems. It was believed that exploration of the potential for a more conservative approach was warranted; the patient was referred for endodontic consultation.
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Cunha et al.
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Case Report/Clinical Techniques
Figure 1. (A) Preoperative periapical radiograph: the maxillary lateral incisor (#7) and the supernumerary tooth are superimposed. (B) Buccal view of #7. (C) Palatal view of tooth #7 showing the small crown of the supernumerary tooth. Note that the crown is discolored when compared with #7.
During clinical examination, a deep cingulum pit was detected on the palatal aspect of tooth #7. Tooth #7 responded normally to hot and cold temperature testing, and the electrical pulp testing (EPT) reading suggested vitality at 36/80. Slight discomfort was noted on vertical percussion of tooth #7, whereas percussing the supernumerary’s crown created an increased pain response. At this point, cold temperature testing and EPT of the supernumerary tooth were performed, which yielded no response to cold and an EPT reading of 80/80. Mobility of tooth #7 was within normal limits, and the supernumerary was not found to move independently from tooth #7. Radiographic evaluation clearly depicted the supernumerary tooth to be overlapped by the lateral incisor. A radiolucent lesion with an ill-defined margin was seen around the apex of the supernumerary tooth, whereas the apical region of the lateral incisor appeared to be intact (Fig. 1). Clinical diagnosis for the lateral incisor was normal pulp and periapical tissues, and the supernumerary tooth was deemed to have a necrotic pulp and symptomatic apical periodontitis. To obtain more detail in regard to the relationship of the supernumerary tooth to its counterpart, a CBCT (Galileos 3D; Sirona Germany, Bensheim, Germany) scan of the anterior maxilla region was obtained.
The scan revealed that the middle portion of the root of the supernumerary tooth was fused to the root of the right lateral incisor (Fig. 2). There was no evidence of communication between the 2 root canal systems. Because of the data acquired from the CBCT scan, extracting the supernumerary tooth was no longer an option because of a high chance of damaging tooth #7, which could ultimately lead to its loss. The possibility of creating a chronic periodontal defect would also have jeopardized tooth #7’s prognosis. Acknowledging that the lateral incisor responded to vitality testing, a conservative approach of nonsurgical root canal treatment of the supernumerary tooth only was decided on. After obtaining local anesthesia and rubber dam isolation, the supernumerary tooth was accessed by using #2 round bur and conic diamond bur. The pulp chamber was then irrigated copiously with 5% sodium hypochlorite (NaOCl). Working length was determined by using an electronic apex locator (ROOT ZX; J Morita, Kyoto, Japan), and cleaning and shaping were performed by using the reciprocating WaveOne system (Primary, 25.08; Dentsply-Tulsa Dental, Tulsa, OK). Patency was checked regularly with #10 hand file (Dentsply-Tulsa Dental). Five percent NaOCl was used as an irrigant throughout the procedure, and 17% EDTA was used for smear layer removal. The canal was then
Figure 2. (A) CBCT scan: axial image of the coronal portion. (B and C) CBCT scan: axial image of the middle portion of the root showing that the teeth are fused. Two separate canals are evident. (D) CBCT scan: axial image of the apical portion revealing that the periradicular lesion involves only the apex of the supernumerary tooth.
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Fusion of Supernumerary Tooth to Maxillary Lateral Incisor
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Case Report/Clinical Techniques
Figure 3. Postoperative radiograph of nonsurgical root canal treatment of supernumerary tooth.
suctioned, dried with paper points, and obturated by using warm vertical compaction in a continuous wave technique with gutta-percha and Kerr Pulp Canal Sealer EWT (Kerr Co, Orange, CA) (Fig. 3). At the 12-month follow-up appointment, the right lateral incisor was testing normal. The fused supernumerary was asymptomatic, and mobility and probing depths were found to be within normal limits. No evidence of periodontal disease associated with either the supernumerary or the lateral incisor (Fig. 4) was detectable. Both the periapical radiograph and the CBCT scan obtained at the follow-up appointment demonstrated apical bone healing. Yearly follow-up examinations will continue to monitor the periapical and periodontal status of this tooth.
Discussion This case report shows a successful outcome after nonsurgical root canal treatment of a supernumerary tooth fused to a vital maxillary lateral incisor in which the root canal systems were not communicating. The most widely accepted theory for the development of supernumerary teeth is the hyperactivity theory, which suggests that supernumeraries are formed as a result of local, independent, conditioned hyperactivity of the dental lamina (1, 2). However, differences in the
studies’ design and population and inconsistencies in the reporting of the findings are among the variables that make the available data on supernumerary teeth questionable. Several studies do not provide any information on the prevalence of affected patients, the site of supernumerary teeth, the average number of supernumerary teeth per patient, and whether they were unilateral or bilateral, making it impossible to gather relevant information related to supernumerary teeth (11). The etiology of tooth fusion is unclear. Possible etiologic factors include genetic predisposition, racial differences, and the impact pushing the developing tooth germs together experienced during trauma (2, 3, 12, 13). It is well-accepted that the frequency of tooth fusion is extremely low, in particular, fusion with a supernumerary tooth (2, 4, 5, 14, 15). When pulpal pathosis affects a fused tooth and communication between the root canal systems exists, nonsurgical root canal treatment of both systems is required to obtain treatment success (5, 6). If the fusion poses an aesthetic problem, the supernumerary tooth may be surgically removed if the level at which the fusion occurred permits such an approach. Restoration of the remaining tooth structure must follow. Although this may be a feasible option in some cases, the long-term periodontal prognosis may be guarded (16). In this present case report, the CBCT scan did not reveal a communication between the root canal systems. As such, nonsurgical root canal treatment could be rendered on the supernumerary tooth only. Extraction of the supernumerary was an option, but the periodontal prognosis would have been compromised. Because the tooth did not pose an aesthetic problem, the patient preferred to maintain the tooth as it was. Diagnosis and treatment planning in cases involving fused teeth are often difficult and frequently require additional diagnostic tools and a multidisciplinary approach (5, 6, 9, 10). In this particular case because of the clinical presentation of symptoms and the tooth’s complex anatomy, it is not unforeseen that this fused supernumerary tooth and potentially its counterpart may have been planned for extraction. The CBCT scan provided invaluable information that prevented the execution of a potentially disastrous treatment plan that would likely have lead to a guarded prognosis for tooth #7 or its removal. Obtaining 3D visualization of the relationship of the supernumerary to its counterpart clearly revealed that they were fused at the enamel and dentin level. Furthermore, the scan showed that no communication existed between the 2 canal systems; therefore, the symptomatic supernumerary could be treated as a separate tooth. The clinical tests performed supported this approach. Analysis of the presence and extension of the fusion afforded by acquiring a CBCT scan allowed for a more accurate and conservative treatment approach to be undertaken with confidence. In conclusion, clinicians should be aware of possible anatomic variations and that thorough diagnosis by using appropriate technology
Figure 4. (A–C) Both 12-month follow-up periapical radiograph and CBCT scan demonstrate apical bone healing.
422
Cunha et al.
JOE — Volume 41, Number 3, March 2015
Case Report/Clinical Techniques is crucial to determine the treatment option that will provide the best outcome. Consultation with specialists in different areas is advised because a multidisciplinary approach may be required, depending on the complexity of the case.
Acknowledgments The authors would like to acknowledge Mr Grant Warren for the arrangement of photos as they are displayed in the figures. The authors deny any conflicts of interest related to this study.
References 1. Regezi JA, Sciubba J, Jordan R. Abnormalities of teeth. In: Regezi JA, Sciubba J, Jordan R, eds. Oral Pathology: Clinic Pathologic Correlations, 6th ed. Philadelphia: Elsevier Saunders; 2012:373–89. 2. Rajendran R. Developmental disturbances of oral and paraoral structures. In: Shafer WG, Hine MK, Levy BM, eds. Shafer’s Textbook of Oral Pathology, 6th ed. Cyber City, India: Elsevier India; 2009:3–79. 3. Tannenbaum AK, Alling EE. Anomalous tooth development: case reports of gemination and twinning. Oral Surg Oral Med Oral Pathol 1963;16:883–8. 4. Tortora C, Meazzini MC, Garattini G, Brusati R. Prevalence of abnormalities in dental structure, position, and eruption pattern in a population of unilateral and bilateral cleft lip and palate patients. Cleft Palate Craniofac J 2008;45: 154–62. 5. Rani AK, Metgud S, Yakub SS, et al. Endodontic and esthetic management of maxillary lateral incisor fused to a supernumerary tooth associated with a talon cusp by
JOE — Volume 41, Number 3, March 2015
6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16.
using spiral computed tomography as a diagnostic aid: a case report. J Endod 2010; 36:345–9. Baratto-Filho F, Leonardi DP, Crozeta BM, et al. The challenges of treating a fused tooth. Braz Dent J 2012;23:256–62. Atasu M, Cimilli H. Fusion of the permanent maxillary right incisor to a supernumerary tooth in association with a gemination of permanent maxillary left central incisor: a dental, genetic and dermatologic study. J Clin Pediatr Dent 2000;24:329–33. Nunes E, de Moraes IG, de Novaes PM, de Sousa SM. Bilateral fusion of mandibular second molars with supernumerary teeth: case report. Braz Dent J 2002;13: 137–41. Katheria BC, Kau CH, Tate R, et al. Effectiveness of impacted and supernumerary tooth diagnosis from traditional radiography versus cone beam computed tomography. Pediatr Dent 2010;32:304–9. Shim YS, Kim AH, Choi JE, An SY. Use of three-dimensional computed tomography images in dental care of children and adolescents in Korea. Technol Health Care 2014;22:333–7. Anthonappa RP, King NM, Rabie ABM. Diagnostic tools used to predict the prevalence of supernumerary teeth: a meta-analysis. Dentomaxillofac Radiol 2012;41: 444–9. Levitas TC. Gemination, fusion, twinning and concrescence. ASDC J Dent Child 1965; 32:93–100. O’Reilly PM. A structural and ultrastructural study of a fused tooth. J Endod 1989;15: 442–6. Ruprecht A, Batniyi S, El-Neweihi E. Double teeth: the incidence of germination and fusion. J Pedodont 1985;9:332–7. Buenviaje TM, Rapp R. Dental anomalies in children: a clinical and radiographic survey. J Dent Child 1984;51:42–6. Kim E, Jou YT. A supernumerary tooth fused to the facial surface of a maxillary permanent central incisor: case report. J Endod 2000;26:45–8.
Fusion of Supernumerary Tooth to Maxillary Lateral Incisor
423
Unilateral Fusion of a Supernumerary Tooth to a Maxillary Permanent Lateral Incisor: A Report of a Rare Case Rodrigo Sanches Cunha, DDS, MSc, PhD, FRCD(C),* Alanna Junaid, BSc DMD BSc (Dent),* and Isabel Mello, DDS, MSc, PhD, FRCD(C)*† Abstract A supernumerary tooth is an additional entity to the normal series of teeth that may occur in isolation or may be fused to a normal counterpart. Diagnosis and delineation of an accurate treatment plan in cases involving supernumerary teeth are often a challenge. This report describes a case of unilateral fusion of a supernumerary tooth to a maxillary permanent lateral incisor in which a conservative approach was used to reach a favorable outcome. (J Endod 2015;41:420–423)
Key Words Anatomy, CBCT, fusion, supernumerary
From the *Division of Endodontics, University of Manitoba, Winnipeg, Manitoba, Canada; and †Division of Endodontics, Dalhousie University, Halifax, Nova Scotia, Canada. Address requests for reprints to Dr Rodrigo Sanches Cunha, Department of Restorative Dentistry, Endodontology, University of Manitoba D226C, 780 Bannatyne Avenue, Winnipeg, MB, Canada R3E 0W2. E-mail address: rodrigo.odonto@ hotmail.com 0099-2399/$ - see front matter Copyright ª 2015 American Association of Endodontists. http://dx.doi.org/10.1016/j.joen.2014.10.021
A
supernumerary tooth is an additional entity to the normal series of teeth and may be seen in any quadrant of the jaws. These teeth may have a normal morphology, or they may be rudimentary and miniature. Supernumerary teeth are much more commonly seen in the maxilla than in the mandible (10 to 1) (1). Tooth fusion results from the union of 2 or more tooth germs during the developmental process and may occur between both the dentin and enamel layers, or it may involve just the enamel layer (2). Both the epithelial and mesenchymal germ layers are involved, which leads to irregularities in tooth morphology (3). In fused teeth the root canal systems may be connected or completely separate, depending on the developmental stage at which the union took place (2). The incidence of fusion is approximately 0.1% in the permanent dentition and 0.5% in the primary dentition in the white population (4). Fusion between supernumerary and permanent teeth occurs less frequently than fusion between other types of teeth (5). Clinically, several complications may occur because of the fusion of teeth such as the development of caries in the groove between the fused crowns, tooth impaction, diastemas, aesthetic and periodontal problems, and pulpal pathosis. Many of these complications demand a multidisciplinary approach, and treatment depends on the type and position of the supernumerary tooth and on its relation to the adjacent teeth (5–8). If incomplete fusion is present and there is no communication of the root canal systems, nonsurgical root canal treatment may be rendered on the affected tooth only, preserving the vitality of the unaffected counterpart. A thorough diagnosis is paramount to the formulation of an accurate treatment plan that will lead to a favorable prognosis. In endodontics, periapical radiographs are mandatory for diagnosis, treatment, and follow-up. However, they provide a limited 2-dimensional view of the true 3-dimensional (3D) anatomy. With the advent of cone-beam computed tomography (CBCT), accurate 3D imaging of teeth and their surrounding dentoalveolar structures is now readily obtainable (9). Because of shorter acquisition times and significant reductions in radiation exposure as compared with conventional CT imaging, CBCT scans are ordered with increasing frequency. The ability to accurately focus on specific regions by using a small field of view further avoids unnecessary radiation exposure and provides a minimally invasive approach to acquiring detailed diagnostic information (10). This report describes a case of unilateral fusion of a supernumerary tooth to a maxillary permanent lateral incisor in which a conservative approach was used to reach a favorable outcome.
Case Report A 20-year-old female white patient was referred to an endodontist for assessment and necessary treatment of her maxillary right lateral incisor (tooth #7). Her chief complaint was of spontaneous pain that necessitated 400 mg ibuprofen be taken every 8 hours for relief. Her medical status was noncontributory. At this stage, the patient had been evaluated by both a periodontist and an oral and maxillofacial surgeon. Collaboratively, they had suggested that the supernumerary tooth lingual to tooth #7 be surgically extracted and that the resultant defect be bone grafted to prevent the development of future periodontal problems. It was believed that exploration of the potential for a more conservative approach was warranted; the patient was referred for endodontic consultation.
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Cunha et al.
JOE — Volume 41, Number 3, March 2015
Case Report/Clinical Techniques
Figure 1. (A) Preoperative periapical radiograph: the maxillary lateral incisor (#7) and the supernumerary tooth are superimposed. (B) Buccal view of #7. (C) Palatal view of tooth #7 showing the small crown of the supernumerary tooth. Note that the crown is discolored when compared with #7.
During clinical examination, a deep cingulum pit was detected on the palatal aspect of tooth #7. Tooth #7 responded normally to hot and cold temperature testing, and the electrical pulp testing (EPT) reading suggested vitality at 36/80. Slight discomfort was noted on vertical percussion of tooth #7, whereas percussing the supernumerary’s crown created an increased pain response. At this point, cold temperature testing and EPT of the supernumerary tooth were performed, which yielded no response to cold and an EPT reading of 80/80. Mobility of tooth #7 was within normal limits, and the supernumerary was not found to move independently from tooth #7. Radiographic evaluation clearly depicted the supernumerary tooth to be overlapped by the lateral incisor. A radiolucent lesion with an ill-defined margin was seen around the apex of the supernumerary tooth, whereas the apical region of the lateral incisor appeared to be intact (Fig. 1). Clinical diagnosis for the lateral incisor was normal pulp and periapical tissues, and the supernumerary tooth was deemed to have a necrotic pulp and symptomatic apical periodontitis. To obtain more detail in regard to the relationship of the supernumerary tooth to its counterpart, a CBCT (Galileos 3D; Sirona Germany, Bensheim, Germany) scan of the anterior maxilla region was obtained.
The scan revealed that the middle portion of the root of the supernumerary tooth was fused to the root of the right lateral incisor (Fig. 2). There was no evidence of communication between the 2 root canal systems. Because of the data acquired from the CBCT scan, extracting the supernumerary tooth was no longer an option because of a high chance of damaging tooth #7, which could ultimately lead to its loss. The possibility of creating a chronic periodontal defect would also have jeopardized tooth #7’s prognosis. Acknowledging that the lateral incisor responded to vitality testing, a conservative approach of nonsurgical root canal treatment of the supernumerary tooth only was decided on. After obtaining local anesthesia and rubber dam isolation, the supernumerary tooth was accessed by using #2 round bur and conic diamond bur. The pulp chamber was then irrigated copiously with 5% sodium hypochlorite (NaOCl). Working length was determined by using an electronic apex locator (ROOT ZX; J Morita, Kyoto, Japan), and cleaning and shaping were performed by using the reciprocating WaveOne system (Primary, 25.08; Dentsply-Tulsa Dental, Tulsa, OK). Patency was checked regularly with #10 hand file (Dentsply-Tulsa Dental). Five percent NaOCl was used as an irrigant throughout the procedure, and 17% EDTA was used for smear layer removal. The canal was then
Figure 2. (A) CBCT scan: axial image of the coronal portion. (B and C) CBCT scan: axial image of the middle portion of the root showing that the teeth are fused. Two separate canals are evident. (D) CBCT scan: axial image of the apical portion revealing that the periradicular lesion involves only the apex of the supernumerary tooth.
JOE — Volume 41, Number 3, March 2015
Fusion of Supernumerary Tooth to Maxillary Lateral Incisor
421
Case Report/Clinical Techniques
Figure 3. Postoperative radiograph of nonsurgical root canal treatment of supernumerary tooth.
suctioned, dried with paper points, and obturated by using warm vertical compaction in a continuous wave technique with gutta-percha and Kerr Pulp Canal Sealer EWT (Kerr Co, Orange, CA) (Fig. 3). At the 12-month follow-up appointment, the right lateral incisor was testing normal. The fused supernumerary was asymptomatic, and mobility and probing depths were found to be within normal limits. No evidence of periodontal disease associated with either the supernumerary or the lateral incisor (Fig. 4) was detectable. Both the periapical radiograph and the CBCT scan obtained at the follow-up appointment demonstrated apical bone healing. Yearly follow-up examinations will continue to monitor the periapical and periodontal status of this tooth.
Discussion This case report shows a successful outcome after nonsurgical root canal treatment of a supernumerary tooth fused to a vital maxillary lateral incisor in which the root canal systems were not communicating. The most widely accepted theory for the development of supernumerary teeth is the hyperactivity theory, which suggests that supernumeraries are formed as a result of local, independent, conditioned hyperactivity of the dental lamina (1, 2). However, differences in the
studies’ design and population and inconsistencies in the reporting of the findings are among the variables that make the available data on supernumerary teeth questionable. Several studies do not provide any information on the prevalence of affected patients, the site of supernumerary teeth, the average number of supernumerary teeth per patient, and whether they were unilateral or bilateral, making it impossible to gather relevant information related to supernumerary teeth (11). The etiology of tooth fusion is unclear. Possible etiologic factors include genetic predisposition, racial differences, and the impact pushing the developing tooth germs together experienced during trauma (2, 3, 12, 13). It is well-accepted that the frequency of tooth fusion is extremely low, in particular, fusion with a supernumerary tooth (2, 4, 5, 14, 15). When pulpal pathosis affects a fused tooth and communication between the root canal systems exists, nonsurgical root canal treatment of both systems is required to obtain treatment success (5, 6). If the fusion poses an aesthetic problem, the supernumerary tooth may be surgically removed if the level at which the fusion occurred permits such an approach. Restoration of the remaining tooth structure must follow. Although this may be a feasible option in some cases, the long-term periodontal prognosis may be guarded (16). In this present case report, the CBCT scan did not reveal a communication between the root canal systems. As such, nonsurgical root canal treatment could be rendered on the supernumerary tooth only. Extraction of the supernumerary was an option, but the periodontal prognosis would have been compromised. Because the tooth did not pose an aesthetic problem, the patient preferred to maintain the tooth as it was. Diagnosis and treatment planning in cases involving fused teeth are often difficult and frequently require additional diagnostic tools and a multidisciplinary approach (5, 6, 9, 10). In this particular case because of the clinical presentation of symptoms and the tooth’s complex anatomy, it is not unforeseen that this fused supernumerary tooth and potentially its counterpart may have been planned for extraction. The CBCT scan provided invaluable information that prevented the execution of a potentially disastrous treatment plan that would likely have lead to a guarded prognosis for tooth #7 or its removal. Obtaining 3D visualization of the relationship of the supernumerary to its counterpart clearly revealed that they were fused at the enamel and dentin level. Furthermore, the scan showed that no communication existed between the 2 canal systems; therefore, the symptomatic supernumerary could be treated as a separate tooth. The clinical tests performed supported this approach. Analysis of the presence and extension of the fusion afforded by acquiring a CBCT scan allowed for a more accurate and conservative treatment approach to be undertaken with confidence. In conclusion, clinicians should be aware of possible anatomic variations and that thorough diagnosis by using appropriate technology
Figure 4. (A–C) Both 12-month follow-up periapical radiograph and CBCT scan demonstrate apical bone healing.
422
Cunha et al.
JOE — Volume 41, Number 3, March 2015
Case Report/Clinical Techniques is crucial to determine the treatment option that will provide the best outcome. Consultation with specialists in different areas is advised because a multidisciplinary approach may be required, depending on the complexity of the case.
Acknowledgments The authors would like to acknowledge Mr Grant Warren for the arrangement of photos as they are displayed in the figures. The authors deny any conflicts of interest related to this study.
References 1. Regezi JA, Sciubba J, Jordan R. Abnormalities of teeth. In: Regezi JA, Sciubba J, Jordan R, eds. Oral Pathology: Clinic Pathologic Correlations, 6th ed. Philadelphia: Elsevier Saunders; 2012:373–89. 2. Rajendran R. Developmental disturbances of oral and paraoral structures. In: Shafer WG, Hine MK, Levy BM, eds. Shafer’s Textbook of Oral Pathology, 6th ed. Cyber City, India: Elsevier India; 2009:3–79. 3. Tannenbaum AK, Alling EE. Anomalous tooth development: case reports of gemination and twinning. Oral Surg Oral Med Oral Pathol 1963;16:883–8. 4. Tortora C, Meazzini MC, Garattini G, Brusati R. Prevalence of abnormalities in dental structure, position, and eruption pattern in a population of unilateral and bilateral cleft lip and palate patients. Cleft Palate Craniofac J 2008;45: 154–62. 5. Rani AK, Metgud S, Yakub SS, et al. Endodontic and esthetic management of maxillary lateral incisor fused to a supernumerary tooth associated with a talon cusp by
JOE — Volume 41, Number 3, March 2015
6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16.
using spiral computed tomography as a diagnostic aid: a case report. J Endod 2010; 36:345–9. Baratto-Filho F, Leonardi DP, Crozeta BM, et al. The challenges of treating a fused tooth. Braz Dent J 2012;23:256–62. Atasu M, Cimilli H. Fusion of the permanent maxillary right incisor to a supernumerary tooth in association with a gemination of permanent maxillary left central incisor: a dental, genetic and dermatologic study. J Clin Pediatr Dent 2000;24:329–33. Nunes E, de Moraes IG, de Novaes PM, de Sousa SM. Bilateral fusion of mandibular second molars with supernumerary teeth: case report. Braz Dent J 2002;13: 137–41. Katheria BC, Kau CH, Tate R, et al. Effectiveness of impacted and supernumerary tooth diagnosis from traditional radiography versus cone beam computed tomography. Pediatr Dent 2010;32:304–9. Shim YS, Kim AH, Choi JE, An SY. Use of three-dimensional computed tomography images in dental care of children and adolescents in Korea. Technol Health Care 2014;22:333–7. Anthonappa RP, King NM, Rabie ABM. Diagnostic tools used to predict the prevalence of supernumerary teeth: a meta-analysis. Dentomaxillofac Radiol 2012;41: 444–9. Levitas TC. Gemination, fusion, twinning and concrescence. ASDC J Dent Child 1965; 32:93–100. O’Reilly PM. A structural and ultrastructural study of a fused tooth. J Endod 1989;15: 442–6. Ruprecht A, Batniyi S, El-Neweihi E. Double teeth: the incidence of germination and fusion. J Pedodont 1985;9:332–7. Buenviaje TM, Rapp R. Dental anomalies in children: a clinical and radiographic survey. J Dent Child 1984;51:42–6. Kim E, Jou YT. A supernumerary tooth fused to the facial surface of a maxillary permanent central incisor: case report. J Endod 2000;26:45–8.
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423
