Case Report/Clinical Techniques
Fusion of Central Incisors with Supernumerary Teeth: A 10-year Follow-up of Multidisciplinary Treatment Nelly Steinbock, DMD,* Ronald Wigler, DMD,* Arye Y. Kaufman, DMD,* Shaul Lin, DMD,* Imad Abu-El Naaj, DMD,† and Dror Aizenbud, DMD, MSc‡ Abstract Introduction: Macrodontia of anterior teeth may occur as an isolated condition or as a result of fusion or gemination and may cause clinical problems such as tooth crowding and esthetic problems. Preliminary planning and careful management are often required by a dental team comprising an orthodontist, an endodontist, a prosthodontist, and an oral surgeon. A multidisciplinary treatment approach in a case with fused teeth is presented. Methods: A 9-year-old girl presented with macrodontia of a left maxillary central incisor. The patient was referred to the orthodontic department because of a large central incisor as a result of fusion with an unspecific supernumerary tooth. The surgical procedure included sectioning off the mesial segment as far as possible, both apically and subgingivally, and extracting 1 of the fused supernumerary teeth. During the sectioning procedure, the pulp of the remaining tooth was exposed at the middle third of the root. Direct pulp capping was performed by an endodontist using mineral trioxide aggregate. Twelve weeks later, orthodontic treatment was commenced, and finally after a 26-month orthodontic treatment period, the central incisors’ crown was restored using composite material. Results: A 10-year clinical and radiographic follow-up revealed that the remaining resected central incisor kept its vitality, and the patient was pleased with the esthetic result. Conclusions: Proper interdisciplinary treatment planning of complicated cases such as anomalous teeth, which involve fusion to a supernumerary tooth, may lead to minimal invasive conservative procedures that maintain tooth vitality and result in a pleasing esthetic result. (J Endod 2014;-:1–5)
Key Words Central incisor, mineral trioxide aggregate, orthodontic, tooth sectioning
O
ccasionally, orthodontists and general dentists encounter patients with macrodontia of anterior teeth as a result of fusion or gemination of maxillary incisors. It is extremely difficult to restore the natural look of such a wide tooth. Furthermore, if a macrodontic tooth is left in the dental arch, it may severely compromise the eruption of adjacent teeth causing occlusal alteration. Fusion and gemination are anomalies with close similarity inherited by different etiologies (1). Fusion is a ‘‘double’’ tooth resulting from the union of 2 adjacent tooth germs (2). According to Regezi et al (3), it may involve the entire length of the teeth or the roots only, in which case cementum and dentin are shared. Root canals also may be separated or shared, which may lead to a reduced number of teeth or may occur between a normal and supernumerary tooth. Concrescence is a form of fusion in which the adjacent, already formed teeth are joined by cementum, which may take place even before the eruption of teeth. Gemination is a disturbance during odontogenesis in which partial cleavage of the tooth germ occurs and results in a tooth that has a double or ‘‘twin’’ crown, it is usually not completely separated, and a common root and pulp space is shared (2). Gemination is an aborted attempt of a tooth bud to divide, and unlike fusion, the root and root canal remain undivided. The typical result is partial cleavage with the appearance of 2 crowns that share the same root canal (3). The prevalence of these anomalies is reported to be less than 1%, occurring predominantly in incisors and canines with apparent equal distribution between the 2 jaws, and more common in deciduous teeth (4). Macrodontia of anterior teeth, whether caused by fusion or gemination, creates problems of crowding and esthetics. The absence of vertical to horizontal crown size harmony (referred to as the ‘‘golden proportions’’) is disturbing and esthetically unacceptable. Orthodontists’ treatment planning requires special attention, and such planning should be performed by a multidisciplinary consultation team comprising endodontists, prosthodontists, and oral surgeons to determine the best treatment approach with the most acceptable outcome. When the treatment includes sectioning off the tooth, part of it may be left intact. In this case, a possible communication between the pulp chambers and/or root canal systems should be considered, and an endodontic specialist should be involved in the process. Proper treatment by an endodontic specialist may include pulp capping using mineral trioxide aggregate (MTA) and avoidance of a complete root canal procedure. Preserving the dental pulp or part of it in a healthy state is important in treating teeth with exposed vital pulp. MTA is a bioactive biocompatible material capable of sealing the pathways of communication between the root canal system and the external surfaces of the teeth and creating an ideal environment for healing (5, 6). When placed in direct contact with pulp tissue, it encourages formation of a calcified bridge, thus creating both a mechanical and biologic seal (6).
From the *Departments of Endodontics and Dental Traumatology, School of Graduate Dentistry, Rambam Health Care Campus, Haifa Israel; and Departments of Oral and Maxillofacial Surgery and ‡Orthodontic and Cranofacial, Rambam Health Care Campus, Technion Faculty of Medicine, Haifa, Israel. Address requests for reprints to Dr Dror Aizenbud, Orthodontic and Craniofacial Department, School of Graduate Dentistry, Rambam Health Care Campus, Haifa, P.O. Box 9602, 31096, Israel. E-mail address: [email protected] 0099-2399/$ - see front matter Copyright ª 2014 American Association of Endodontists. http://dx.doi.org/10.1016/j.joen.2013.12.004 †
JOE — Volume -, Number -, - 2014
Fusion of Central Incisors
1
Case Report/Clinical Techniques The aim of this case report was to describe a 10-year outcome of a combined treatment of a fused maxillary incisor by means of an orthodontic–endodontic–prosthodontic–oral surgery management protocol.
Case Report A 9-year-old girl was referred for treatment in the year of 2002 while presenting with macrodontia of a left maxillary central incisor because of esthetic complaints (Fig. 1A). The remaining primary and permanent teeth were of normal size and shape, and the number of teeth was not reduced. Family and medical history were noncontributory. Clinically, the maxillary left central incisor and an unspecific supernumerary tooth appeared as fused teeth at the cervical third of the crowns, whereas separated roots could be diagnosed in the panoramic and periapical views (Fig. 1B and C [see arrows]). This may also be considered gemination with a deep vertical groove dividing the tooth in the coronal two thirds to 2 conical-shaped parts wherein the distal segment was wider. The total mesiodistal width of the fused left crown was 15 mm compared with 10 mm of the right (normal) central incisor crown. The resulting dental crowding of the maxillary incisor region caused a shifting of the fused distal segment toward the buccal (distobuccal rotation) compared with the mesial segment (Fig. 1). The vitality test was conclusive, showing a normal response to the cold test (Endo Ice; Hygenic, Akron, OH). Radiographically, 2 distinct roots united by the cementum were apparent (Fig. 1B and C), and a diagnosis of normal pulp with normal apical tissues and fusion of the left central incisor with an unspecific supernumerary tooth was established by means of clinical and radiographic examination.
The surgical treatment plan included sectioning off the mesial segment as far as possible, both apically and subgingivally, in order to extract the mesial (small) fused tooth. The procedure was performed under local anesthesia. No premedication was required. No special preparation of the oral cavity was implemented. A fullthickness buccal and palatal gingival mucoperiosteal envelope flap was performed (Fig. 2A). A sharp osteotome was placed at the incisal notch groove site aligned obliquely (distally) to the long axis of the root in order to section the crown and part of the root. A sharp tap with a mallet sectioned off the undesirable part of the oversized crown (fused supernumerary). The plane of the separation was terminated subgingivally as preoperatively desired and directed by angling the osteotome. During the sectioning, a 4-mm-wide oval hole was observed at the midthird of the root, and the pulp was observed through it. The hole was filled with MTA using a dental spatula and burnished on the root surface to facilitate direct pulp capping (Fig. 2B). Before flap suturing, nonrotary bone contouring was performed to remove sharp margins and to enable tight covering of the original gingival tissue over the MTA site. After a 12-week asymptomatic follow-up period (Fig. 3A), the orthodontic treatment was initiated. The patient was diagnosed with skeletal class II and an Angle class II division I malocclusion. The pattern of jaw growth was normal, and a slightly constricted maxilla was diagnosed; however, no crossbite was recorded. Maxillary incisor dental crowding was noted. Orthodontic treatment extended over a period of 3.5 years (Fig. 3C). After achieving all orthodontic goals, composite restoration was applied to the sectioned maxillary central incisor in order to achieve final esthetics by mimicking the right central incisor
Figure 1. The preoperative macrodontic maxillary left central incisor fused to an unspecific supernumerary tooth. (A) The intraoral frontal view. (B) The panoramic radiograph view. (C) The periapical radiograph view. The arrows point to the separate root.
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Case Report/Clinical Techniques
Figure 2. The surgical procedure. (A) A full-thickness buccal and palatal gingival mucoperiosteal envelope flap raised, facilitating sectioning off of the undesirable part of the oversized crown (fused supernumerary tooth). (B) Periapical radiograph views of the tooth after removal of the extra tooth material (supernumerary tooth) and the application of MTA performing direct pulp capping.
(Fig. 3C). Periapical radiographs that were taken right before (Fig. 3B) and immediately after orthodontic treatment (Fig. 3D) revealed a good healing process of the sectioned incisor.
Follow-up Follow-up appointments included standard orthodonticrestorative-endodontic clinical examination and vitality tests at 6-month intervals. A periapical radiograph was annually performed during the first 3 years. After 3 years, because of relocation, the patient declined recall and reappeared 10 years after surgery.
Ten years postoperatively, the tooth preserved its vitality. The pulp was evaluated by means of lack of symptoms, vital signs by pulp testing, and the normal periapical area as determined through the radiographs. The composite restoration was intact with no clinical or radiographic signs of secondary carries, and replacement was recommended because of discoloration (Fig. 4A–C).
Discussion The presence of an abnormally sized anterior tooth with a funnyshaped crown presents a challenge that is difficult to treat by conventional
Figure 3. Pre- and post-orthodontic treatment stage. (A) The preorthodontic intraoral frontal view of the asymptomatic maxillary left central incisor taken after sectioning off the fused supernumerary teeth and MTA sealing. (B) The preorthodontic periapical radiograph view. (C) The intraoral frontal view at the end of the orthodontic treatment and after performance of composite restoration to achieve final esthetics by mimicking the dimensions of the right maxillary central incisor’s crown. (D) The postorthodontic periapical radiograph view.
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Case Report/Clinical Techniques
Figure 4. Ten-year follow-up revealing an asymptomatic vital left maxillary central incisor, a stable anterior and posterior occlusal relationship, and esthetically pleasing dental and facial appearance of the original composite restoration. (A) The intraoral frontal view. (B) The panoramic radiograph view. (C) The periapical radiograph view.
orthodontic treatment planning. Matching maxillary and mandibular midlines may not be possible, and ‘‘ideal’’ overbite and overjet measurements may be compromised. Clinically, it is difficult, if not impossible, to differentiate fusion from gemination when supernumerary teeth are involved. However, the aim of the treatment and the protocol are the same. In this case, a full-thickness buccal and palatal gingival mucoperiosteal envelope flap was performed under local anesthesia containing lidocaine + 1:100,000 epinephrine, facilitating sectioning off the root and part of the crown and removal of the extra tooth material (supernumerary tooth) by an osteotome. The resulting wide whole in the root area included pulp exposure that was sealed with MTA, thus forming direct pulp capping. Consequently, a normal dimension of the maxillary central incisor crown was restored, enabling a normal class I occlusion and better esthetics. The communication between the pulp chambers and/or root canal systems of fused or geminated teeth is a known fact (7, 8). Treatment planning for surgical exposure should be considered when performing sectioning of the malformed tooth. Although root canal treatment is routinely considered in these cases (4), it may be avoided if the exposed site is not infected and is limited in size by performing pulp capping using MTA. With this method, remaining coronal and radicular pulp tissue preservation is expected. MTA may induce the healing process of the exposed pulp tissue including reorganization of the soft tissue, differentiation of odontoblast-like cells from subodontoblast cells, and repair of the exposed dentine tissue with reparative dentine bridge formation (6). According to Parirokh and Torabinejad (6), MTA is a promising material for preserving pulp tissue when used as capping material after partial or total pulpotomy. The study by Pitt Ford et al (5) on monkeys showed that most of the pulps that were capped with MTA were free of inflammation, and all of them showed formation of a calcified bridge after 5 months. In the study by Salako et al (9) with rats, MTA proved 4
Steinbock et al.
to be the ideal agent in terms of dentin bridge formation and preserving normal pulpal architecture. The radiographs taken throughout the treatment and follow-up period show a reduction in the thickness of the layer of MTA (Figs. 2B, 3D, and 4C). It is known that MTA possesses dissolution characteristics (10). The bioactivity of MTA is explained by the release of Ca and the resultant formation of hydroxyapatite. This suggests that MTA could be used to repair procedural accidents as well as intentional pulp capping as described in the present case report. The vicinity of the location of the procedure to the gingival margin could be elaborated to the extended MTA dissolution as marginal gingivitis, which is a common phenomenon in orthodontic cases and could cause pH reduction, which affects MTA solubility (11). A decision must be made about the treatment options and eventual restoration of the anterior segment. Extraction is considered a poor solution during childhood and adolescence because an implant is not recommended until skeletal maturation (12). Alternative treatment options might be closure of the edentulous space and substitution of the ipsilateral lateral incisor as the central incisor or autotransplantation. However, the patient must have an arch-length deficiency and dental arch asymmetry, so that a premolar from a posterior quadrant can be transplanted to the edentulous site. Generally, teeth surrounded by healthy periodontal tissues yield a very high longevity rate (over 50 years in up to 99.5%) (13). Likewise, periodontally compromised yet treated and maintained teeth and endodontically compromised but successfully treated nonvital teeth yield high survival rates. Currently, oral implant survival rates (82%–94%) do not surpass the longevity of even compromised but successfully treated natural teeth. Because of these difficulties and the high longevity of treated and maintained teeth, dentists should avoid extraction whenever possible. Reduction of the over plus crown size in order to achieve a normal JOE — Volume -, Number -, - 2014
Case Report/Clinical Techniques crown is a preferable and a conservative treatment option in macrodontic tooth cases. If the pulp is exposed during sectioning of the crown, pulp capping should be performed. If the pulp is injured, root canal treatment should be performed.
Conclusion Successful orthodontic-endodontic-surgical treatment of a central incisor fused with a supernumerary tooth was presented. Although there was communication between parts of the pulp chambers, root canal treatment was avoided because of the vital pulp therapy that was performed. Proper clinical and radiographic multidisciplinary examination, correct diagnosis, and treatment planning are key features of successful vital treatment. The novelty of this case is the multidisciplinary modern approach toward a macrodontia that was taken, which resulted in keeping the tooth vital as documented in the long-term follow-up period of 10 years.
Acknowledgments The authors deny any conflicts of interest related to this study.
References 1. Tsesis I, Steinbock N, Rosenberg E, et al. Endodontic treatment of developmental anomalies in posterior teeth: treatment of geminated/fused teeth—report of two cases. Int Endod J 2003;36:372–9.
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2. Glossary of Endodontic Terms, 8th ed. American Chicago: Association of Endodontists; 2012. 3. Oral pathology clinical pathologic correlations. In: Regezi A, Scuibba J, Jordan CK. Abnormalities of Teeth, 4th ed. Philadelphia: Saunders; 2003:367–84. 4. Levitas TC. Gemination, fusion, twinning, and concrescence. ASDC J Dent Child 1965;32:93–100. 5. Pitt Ford TR, Torabinejad M, Abedi HR, et al. Using mineral trioxide aggregate as a pulp-capping material. J Am Dent Assoc 1996;127:1491–4. 6. Parirokh M, Torabinejad M. Mineral trioxide aggregate: a comprehensive literature review—part III: clinical applications, drawbacks, and mechanism of action. J Endod 2010;36:400–13. 7. Libfeld H, Stabholz A, Friedman S. Endodontic therapy of bilaterally geminated permanent maxillary central incisors. J Endod 1986;12:214–6. 8. 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. 9. Salako N, Joseph B, Ritwik P, et al. Comparison of bioactive glass, mineral trioxide aggregate, ferric sulfate, and formocresol as pulpotomy agents in rat molar. Dent Traumatol 2003;19:314–20. 10. Bozeman TB, Lemon RR, Eleazer PD. Elemental analysis of crystal precipitate from gray and white MTA. J Endod 2006;32:425–8. 11. Shie MY, Huang TH, Kao CT, et al. The effect of a physiologic solution pH on properties of white mineral trioxide aggregate. J Endod 2009;35: 98–101. 12. Thilander B, Odman J, Gr€ondahl K, et al. Osseointegrated implants in adolescents. An alternative in replacing missing teeth? Eur J Orthod 1994;16: 84–95. 13. Holm-Pedersen P, Lang NP, M€uller F. What are the longevities of teeth and oral implants? Clin Oral Implants Res 2007;18:15–9.
Fusion of Central Incisors
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Fusion of Central Incisors with Supernumerary Teeth: A 10-year Follow-up of Multidisciplinary Treatment Nelly Steinbock, DMD,* Ronald Wigler, DMD,* Arye Y. Kaufman, DMD,* Shaul Lin, DMD,* Imad Abu-El Naaj, DMD,† and Dror Aizenbud, DMD, MSc‡ Abstract Introduction: Macrodontia of anterior teeth may occur as an isolated condition or as a result of fusion or gemination and may cause clinical problems such as tooth crowding and esthetic problems. Preliminary planning and careful management are often required by a dental team comprising an orthodontist, an endodontist, a prosthodontist, and an oral surgeon. A multidisciplinary treatment approach in a case with fused teeth is presented. Methods: A 9-year-old girl presented with macrodontia of a left maxillary central incisor. The patient was referred to the orthodontic department because of a large central incisor as a result of fusion with an unspecific supernumerary tooth. The surgical procedure included sectioning off the mesial segment as far as possible, both apically and subgingivally, and extracting 1 of the fused supernumerary teeth. During the sectioning procedure, the pulp of the remaining tooth was exposed at the middle third of the root. Direct pulp capping was performed by an endodontist using mineral trioxide aggregate. Twelve weeks later, orthodontic treatment was commenced, and finally after a 26-month orthodontic treatment period, the central incisors’ crown was restored using composite material. Results: A 10-year clinical and radiographic follow-up revealed that the remaining resected central incisor kept its vitality, and the patient was pleased with the esthetic result. Conclusions: Proper interdisciplinary treatment planning of complicated cases such as anomalous teeth, which involve fusion to a supernumerary tooth, may lead to minimal invasive conservative procedures that maintain tooth vitality and result in a pleasing esthetic result. (J Endod 2014;-:1–5)
Key Words Central incisor, mineral trioxide aggregate, orthodontic, tooth sectioning
O
ccasionally, orthodontists and general dentists encounter patients with macrodontia of anterior teeth as a result of fusion or gemination of maxillary incisors. It is extremely difficult to restore the natural look of such a wide tooth. Furthermore, if a macrodontic tooth is left in the dental arch, it may severely compromise the eruption of adjacent teeth causing occlusal alteration. Fusion and gemination are anomalies with close similarity inherited by different etiologies (1). Fusion is a ‘‘double’’ tooth resulting from the union of 2 adjacent tooth germs (2). According to Regezi et al (3), it may involve the entire length of the teeth or the roots only, in which case cementum and dentin are shared. Root canals also may be separated or shared, which may lead to a reduced number of teeth or may occur between a normal and supernumerary tooth. Concrescence is a form of fusion in which the adjacent, already formed teeth are joined by cementum, which may take place even before the eruption of teeth. Gemination is a disturbance during odontogenesis in which partial cleavage of the tooth germ occurs and results in a tooth that has a double or ‘‘twin’’ crown, it is usually not completely separated, and a common root and pulp space is shared (2). Gemination is an aborted attempt of a tooth bud to divide, and unlike fusion, the root and root canal remain undivided. The typical result is partial cleavage with the appearance of 2 crowns that share the same root canal (3). The prevalence of these anomalies is reported to be less than 1%, occurring predominantly in incisors and canines with apparent equal distribution between the 2 jaws, and more common in deciduous teeth (4). Macrodontia of anterior teeth, whether caused by fusion or gemination, creates problems of crowding and esthetics. The absence of vertical to horizontal crown size harmony (referred to as the ‘‘golden proportions’’) is disturbing and esthetically unacceptable. Orthodontists’ treatment planning requires special attention, and such planning should be performed by a multidisciplinary consultation team comprising endodontists, prosthodontists, and oral surgeons to determine the best treatment approach with the most acceptable outcome. When the treatment includes sectioning off the tooth, part of it may be left intact. In this case, a possible communication between the pulp chambers and/or root canal systems should be considered, and an endodontic specialist should be involved in the process. Proper treatment by an endodontic specialist may include pulp capping using mineral trioxide aggregate (MTA) and avoidance of a complete root canal procedure. Preserving the dental pulp or part of it in a healthy state is important in treating teeth with exposed vital pulp. MTA is a bioactive biocompatible material capable of sealing the pathways of communication between the root canal system and the external surfaces of the teeth and creating an ideal environment for healing (5, 6). When placed in direct contact with pulp tissue, it encourages formation of a calcified bridge, thus creating both a mechanical and biologic seal (6).
From the *Departments of Endodontics and Dental Traumatology, School of Graduate Dentistry, Rambam Health Care Campus, Haifa Israel; and Departments of Oral and Maxillofacial Surgery and ‡Orthodontic and Cranofacial, Rambam Health Care Campus, Technion Faculty of Medicine, Haifa, Israel. Address requests for reprints to Dr Dror Aizenbud, Orthodontic and Craniofacial Department, School of Graduate Dentistry, Rambam Health Care Campus, Haifa, P.O. Box 9602, 31096, Israel. E-mail address: [email protected] 0099-2399/$ - see front matter Copyright ª 2014 American Association of Endodontists. http://dx.doi.org/10.1016/j.joen.2013.12.004 †
JOE — Volume -, Number -, - 2014
Fusion of Central Incisors
1
Case Report/Clinical Techniques The aim of this case report was to describe a 10-year outcome of a combined treatment of a fused maxillary incisor by means of an orthodontic–endodontic–prosthodontic–oral surgery management protocol.
Case Report A 9-year-old girl was referred for treatment in the year of 2002 while presenting with macrodontia of a left maxillary central incisor because of esthetic complaints (Fig. 1A). The remaining primary and permanent teeth were of normal size and shape, and the number of teeth was not reduced. Family and medical history were noncontributory. Clinically, the maxillary left central incisor and an unspecific supernumerary tooth appeared as fused teeth at the cervical third of the crowns, whereas separated roots could be diagnosed in the panoramic and periapical views (Fig. 1B and C [see arrows]). This may also be considered gemination with a deep vertical groove dividing the tooth in the coronal two thirds to 2 conical-shaped parts wherein the distal segment was wider. The total mesiodistal width of the fused left crown was 15 mm compared with 10 mm of the right (normal) central incisor crown. The resulting dental crowding of the maxillary incisor region caused a shifting of the fused distal segment toward the buccal (distobuccal rotation) compared with the mesial segment (Fig. 1). The vitality test was conclusive, showing a normal response to the cold test (Endo Ice; Hygenic, Akron, OH). Radiographically, 2 distinct roots united by the cementum were apparent (Fig. 1B and C), and a diagnosis of normal pulp with normal apical tissues and fusion of the left central incisor with an unspecific supernumerary tooth was established by means of clinical and radiographic examination.
The surgical treatment plan included sectioning off the mesial segment as far as possible, both apically and subgingivally, in order to extract the mesial (small) fused tooth. The procedure was performed under local anesthesia. No premedication was required. No special preparation of the oral cavity was implemented. A fullthickness buccal and palatal gingival mucoperiosteal envelope flap was performed (Fig. 2A). A sharp osteotome was placed at the incisal notch groove site aligned obliquely (distally) to the long axis of the root in order to section the crown and part of the root. A sharp tap with a mallet sectioned off the undesirable part of the oversized crown (fused supernumerary). The plane of the separation was terminated subgingivally as preoperatively desired and directed by angling the osteotome. During the sectioning, a 4-mm-wide oval hole was observed at the midthird of the root, and the pulp was observed through it. The hole was filled with MTA using a dental spatula and burnished on the root surface to facilitate direct pulp capping (Fig. 2B). Before flap suturing, nonrotary bone contouring was performed to remove sharp margins and to enable tight covering of the original gingival tissue over the MTA site. After a 12-week asymptomatic follow-up period (Fig. 3A), the orthodontic treatment was initiated. The patient was diagnosed with skeletal class II and an Angle class II division I malocclusion. The pattern of jaw growth was normal, and a slightly constricted maxilla was diagnosed; however, no crossbite was recorded. Maxillary incisor dental crowding was noted. Orthodontic treatment extended over a period of 3.5 years (Fig. 3C). After achieving all orthodontic goals, composite restoration was applied to the sectioned maxillary central incisor in order to achieve final esthetics by mimicking the right central incisor
Figure 1. The preoperative macrodontic maxillary left central incisor fused to an unspecific supernumerary tooth. (A) The intraoral frontal view. (B) The panoramic radiograph view. (C) The periapical radiograph view. The arrows point to the separate root.
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Case Report/Clinical Techniques
Figure 2. The surgical procedure. (A) A full-thickness buccal and palatal gingival mucoperiosteal envelope flap raised, facilitating sectioning off of the undesirable part of the oversized crown (fused supernumerary tooth). (B) Periapical radiograph views of the tooth after removal of the extra tooth material (supernumerary tooth) and the application of MTA performing direct pulp capping.
(Fig. 3C). Periapical radiographs that were taken right before (Fig. 3B) and immediately after orthodontic treatment (Fig. 3D) revealed a good healing process of the sectioned incisor.
Follow-up Follow-up appointments included standard orthodonticrestorative-endodontic clinical examination and vitality tests at 6-month intervals. A periapical radiograph was annually performed during the first 3 years. After 3 years, because of relocation, the patient declined recall and reappeared 10 years after surgery.
Ten years postoperatively, the tooth preserved its vitality. The pulp was evaluated by means of lack of symptoms, vital signs by pulp testing, and the normal periapical area as determined through the radiographs. The composite restoration was intact with no clinical or radiographic signs of secondary carries, and replacement was recommended because of discoloration (Fig. 4A–C).
Discussion The presence of an abnormally sized anterior tooth with a funnyshaped crown presents a challenge that is difficult to treat by conventional
Figure 3. Pre- and post-orthodontic treatment stage. (A) The preorthodontic intraoral frontal view of the asymptomatic maxillary left central incisor taken after sectioning off the fused supernumerary teeth and MTA sealing. (B) The preorthodontic periapical radiograph view. (C) The intraoral frontal view at the end of the orthodontic treatment and after performance of composite restoration to achieve final esthetics by mimicking the dimensions of the right maxillary central incisor’s crown. (D) The postorthodontic periapical radiograph view.
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Case Report/Clinical Techniques
Figure 4. Ten-year follow-up revealing an asymptomatic vital left maxillary central incisor, a stable anterior and posterior occlusal relationship, and esthetically pleasing dental and facial appearance of the original composite restoration. (A) The intraoral frontal view. (B) The panoramic radiograph view. (C) The periapical radiograph view.
orthodontic treatment planning. Matching maxillary and mandibular midlines may not be possible, and ‘‘ideal’’ overbite and overjet measurements may be compromised. Clinically, it is difficult, if not impossible, to differentiate fusion from gemination when supernumerary teeth are involved. However, the aim of the treatment and the protocol are the same. In this case, a full-thickness buccal and palatal gingival mucoperiosteal envelope flap was performed under local anesthesia containing lidocaine + 1:100,000 epinephrine, facilitating sectioning off the root and part of the crown and removal of the extra tooth material (supernumerary tooth) by an osteotome. The resulting wide whole in the root area included pulp exposure that was sealed with MTA, thus forming direct pulp capping. Consequently, a normal dimension of the maxillary central incisor crown was restored, enabling a normal class I occlusion and better esthetics. The communication between the pulp chambers and/or root canal systems of fused or geminated teeth is a known fact (7, 8). Treatment planning for surgical exposure should be considered when performing sectioning of the malformed tooth. Although root canal treatment is routinely considered in these cases (4), it may be avoided if the exposed site is not infected and is limited in size by performing pulp capping using MTA. With this method, remaining coronal and radicular pulp tissue preservation is expected. MTA may induce the healing process of the exposed pulp tissue including reorganization of the soft tissue, differentiation of odontoblast-like cells from subodontoblast cells, and repair of the exposed dentine tissue with reparative dentine bridge formation (6). According to Parirokh and Torabinejad (6), MTA is a promising material for preserving pulp tissue when used as capping material after partial or total pulpotomy. The study by Pitt Ford et al (5) on monkeys showed that most of the pulps that were capped with MTA were free of inflammation, and all of them showed formation of a calcified bridge after 5 months. In the study by Salako et al (9) with rats, MTA proved 4
Steinbock et al.
to be the ideal agent in terms of dentin bridge formation and preserving normal pulpal architecture. The radiographs taken throughout the treatment and follow-up period show a reduction in the thickness of the layer of MTA (Figs. 2B, 3D, and 4C). It is known that MTA possesses dissolution characteristics (10). The bioactivity of MTA is explained by the release of Ca and the resultant formation of hydroxyapatite. This suggests that MTA could be used to repair procedural accidents as well as intentional pulp capping as described in the present case report. The vicinity of the location of the procedure to the gingival margin could be elaborated to the extended MTA dissolution as marginal gingivitis, which is a common phenomenon in orthodontic cases and could cause pH reduction, which affects MTA solubility (11). A decision must be made about the treatment options and eventual restoration of the anterior segment. Extraction is considered a poor solution during childhood and adolescence because an implant is not recommended until skeletal maturation (12). Alternative treatment options might be closure of the edentulous space and substitution of the ipsilateral lateral incisor as the central incisor or autotransplantation. However, the patient must have an arch-length deficiency and dental arch asymmetry, so that a premolar from a posterior quadrant can be transplanted to the edentulous site. Generally, teeth surrounded by healthy periodontal tissues yield a very high longevity rate (over 50 years in up to 99.5%) (13). Likewise, periodontally compromised yet treated and maintained teeth and endodontically compromised but successfully treated nonvital teeth yield high survival rates. Currently, oral implant survival rates (82%–94%) do not surpass the longevity of even compromised but successfully treated natural teeth. Because of these difficulties and the high longevity of treated and maintained teeth, dentists should avoid extraction whenever possible. Reduction of the over plus crown size in order to achieve a normal JOE — Volume -, Number -, - 2014
Case Report/Clinical Techniques crown is a preferable and a conservative treatment option in macrodontic tooth cases. If the pulp is exposed during sectioning of the crown, pulp capping should be performed. If the pulp is injured, root canal treatment should be performed.
Conclusion Successful orthodontic-endodontic-surgical treatment of a central incisor fused with a supernumerary tooth was presented. Although there was communication between parts of the pulp chambers, root canal treatment was avoided because of the vital pulp therapy that was performed. Proper clinical and radiographic multidisciplinary examination, correct diagnosis, and treatment planning are key features of successful vital treatment. The novelty of this case is the multidisciplinary modern approach toward a macrodontia that was taken, which resulted in keeping the tooth vital as documented in the long-term follow-up period of 10 years.
Acknowledgments The authors deny any conflicts of interest related to this study.
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Fusion of Central Incisors
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