Treatment Strategies for Missing Maxillary Central Incisor—An Orthodontist’s Perspective Rajaganesh Gautam, MDS, DNB,1 Purvaja Nene, MDS,2 Kunal Mehta, MDS,3 Salil Nene, MDS,1 Ashwith Hegde, MDS,4 & Rajbala Jaju, BDS, MOM, Associate Fellow AAID5 1
Professor, Department of Orthodontics, M.A. Rangoonwala Dental College & Research Center, Pune, India Reader, Department of Prosthodontics, M.A. Rangoonwala Dental College & Research Center, Pune, India 3 Senior Lecturer, Department of Orthodontics, M.A. Rangoonwala Dental College & Research Center, Pune, India 4 Reader, Department of Orthodontics, M.A. Rangoonwala Dental College & Research Center, Pune, India 5 Doctor, Private practice, Abu Dhabi, UAE 2
Keywords Missing maxillary central incisor; orthodontic management; canine substitution; lateral incisor substitution; prosthodontic rehabilitation; esthetic considerations. Correspondence Kunal Mehta, Dept. of Orthodontics, M.A. Rangoonwala Dental College & Research Center, Azam Campus, Pune 411001, India. E-mail: [email protected]
Abstract The loss of maxillary central incisors at an early age has psychological, esthetic, and functional implications. Multiple treatment options are available for replacing missing central incisors. The management demands a multidisciplinary approach involving the orthodontist, prosthodontist, and periodontist. Treatment planning requires consideration of a variety of clinical and nonclinical factors. This clinical report attempts to demonstrate different strategies for the management of unilaterally and bilaterally missing central incisors.
The authors deny any conflicts of interest. Accepted September 3, 2013 doi: 10.1111/jopr.12133
The maxillary central incisors play an important role in smile esthetics, function, and speech. One or both missing central incisors are often encountered in clinical practice in patients who have had traumatically avulsed central incisors or a germinated or fused maxillary central incisor that must be extracted.1 At times, agenesis of maxillary central incisors is also encountered.2 A missing maxillary central incisor can have psychological implications due to poor smile esthetics and improper speech and is thus indicated for replacement. There are many choices for replacement of a missing maxillary central incisor. If the tooth has been avulsed, the simplest long-term solution is reimplantation. If that is not possible, autotransplantation can be considered; however, the patient must have an arch length deficiency, so a premolar from a posterior quadrant can be transplanted to the edentulous site. A third option is maintenance of the edentulous space during childhood and adolescence and placement of a fixed partial denture (FPD) or an implant when the patient is an adult. A fourth possible solution is to close the edentulous space and substitute the ipsilateral lateral incisor for the central incisor.1 In deciding on the above treatment options, a variety of clinical and nonclinical factors, including the patient’s age and facial morphology, space available, width of lateral incisor and length of its root, size and
shape of teeth, color and morphology of canines, nature of any malocclusion and cuspal interdigitation, risk of future trauma, and the patient’s willingness to undergo complex, expensive treatment, must be considered.3,4 Factors for optimal esthetics
Mesiodistal position of the lateral incisor The maxillary lateral incisor is narrower and shorter than the central incisor. Also, the emergence profile of maxillary central incisors is generally flat on the mesial surface. This warrants the lateral incisor be moved close to the midline so an artificial crown can be made wider on the distal than on the mesial aspect for optimal esthetics.1,5 Matching the gingival margins of the maxillary anterior teeth The lateral incisor must be intruded so its gingival margin matches the usual gingival margin position of the central incisor.6-9 Additional intrusion also allows restoration of this tooth into the shape of a central incisor.1 Gingivectomy of the lateral incisor can also increase the clinical crown height.10 The
C 2014 by the American College of Prosthodontists Journal of Prosthodontics 23 (2014) 509–513
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maxillary canine must be extruded to move its gingival margin incisally to resemble the usual gingival margin position of the lateral incisor.1 Angulation of the lateral incisor When a unilateral central incisor is missing, it is helpful if the lateral incisor and adjacent central incisor are left more parallel than normal.11 In bilateral cases, both lateral incisors should be kept parallel to each other. Reshaping of the canine Recontouring and reshaping of the canine should be considered to give proper shape and size of a lateral incisor. The tip of the canine should be flat, the disto-incisal line angle should be rounded, and there should be proper mesiodistal reduction. The canine eminence on the labial surface should be reduced to make it flat.12 The lingual contour should be reduced to enhance adequate overbite and overjet and to eliminate prematurities.12 Reshaping of the first premolar The composite build-up of the buccal cusp of the first premolar may be required to provide optimum esthetics.13
1. Extraction of mandibular right first premolar to relieve the crowding in the mandibular arch 2. Mesial movement of maxillary right lateral incisor into the central incisor space and its conversion into central incisor and also lateralization of the maxillary right canine. 3. Maxillary midline correction by distal movement of maxillary left central incisor. The treatment plan was discussed with the patient with the aid of a Kesling’s diagnostic set-up. The treatment was divided into three phases: orthodontic, periodontal, and prosthetic. In the orthodontic phase, the maxillary left central incisor was moved distally to align its mesial margin with the facial midline. The maxillary right lateral incisor was moved mesially into the central incisor position and was also intruded so its gingival margin would match that of the adjacent central incisor after gingivectomy. The lower arch was leveled and aligned after right premolar extraction. At the completion of orthodontic treatment (Fig 2), the result was retained with a lingual-bonded retainer until the age of 18 years, and the commencement of the final periodontal and prosthetic phase. In the periodontal phase, gingivectomy for the maxillary lateral incisor was carried out to match its gingival margin with that of the adjacent central incisor. In the prosthetic phase the mesialized lateral incisor was restored with an all-ceramic crown to resemble the adjacent central incisor (Fig 3).
Shade matching
Clinical report 2 Care should be taken for optimum color matching between the so-called central and lateral incisors.14 Other factors for optimal static and functional occlusion such as labio-palatal position of the lateral incisor, vertical height of the lateral incisor crown, labiolingual inclination of the canines,11 posterior occlusion,12 and reshaping of the palatal cusp of the first premolar14,15 should also be evaluated and considered. It is strongly recommended that a Kesling’s diagnostic set-up be done in these cases to visualize the final occlusion and “fit” and also to quantify the above-stated modifications in pretreatment study models before proceeding with the actual clinical steps.
Clinical report 1 A 13-year-old boy reported to the orthodontic clinic with spacing in the upper anterior teeth and crowded lower dentition (Fig 1). He had a history of trauma and loss of an anterior tooth when he was 10 years old. Intraoral examination showed a missing maxillary right central incisor and mesial drifting of the maxillary left central incisor and right lateral incisor resulting in moderate anterior spacing. The maxillary dental midline was shifted to the right by 4 mm. The mandibular arch showed 6 mm crowding. The patient had Angle’s class I molar relation on both sides. Radiographic examination showed a missing maxillary right central incisor and good periodontal and periapical health of the adjacent incisors. After all treatment possibilities were considered, the following treatment plan was finalized510
A 28-year-old female patient presented with the chief compliant of being unhappy with her smile. She gave a history of previously extracted upper central incisors and was wearing an acrylic removable partial denture (RPD). On clinical examination (Fig 4) she presented with a class I molar relation on the right side and a Class II molar relation on the left side. Her lower left first molar was previously extracted with mesial migration of the lower left second molar. She had an edentulous anterior ridge due to the previously extracted central incisors, with space loss due to mesial migration of the adjacent teeth. The upper anterior arch form was flattened, with mild crowding and open bite in the left lateral incisor canine segment. Her upper left second molar was in complete buccal crossbite. She had mild spacing in the lower anteriors, with the lower right first premolar buccally blocked out. Her lower dental midline was shifted to the left. Extraorally, she had mildly protrusive lips and a straight profile. First, the possibility of replacing her missing upper central incisors with an implant prosthesis was explored but ruled out due to lack of sufficient buccolingual bone width in the edentulous segment due to the long-standing edentulous history (Fig 5). Implants in the region would have necessitated some form of bone augmentation for improving ridge width. The patient was then referred for an orthodontic opinion, and the orthodontist suggested the possibility of comprehensive orthodontic treatment, in which the anterior edentulous space could be completely closed. In the lower arch, with the extraction of the lower right first premolar, crowding and midline correction could be achieved. It was also decided to extract the
C 2014 by the American College of Prosthodontists Journal of Prosthodontics 23 (2014) 509–513
Gautam et al
Strategies for Missing Maxillary Central Incisor
Figure 1 Pretreatment intra- and extraoral views.
Figure 2 Postorthodontic intra- and extraoral views.
Figure 3 Postprosthetic rehabilitation intra- and extraoral views.
Figure 4 Pretreatment intra- and extraoral views.
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Figure 5 Pretreatment study models.
upper left third molar to allow crossbite correction in the second molar region. This possibility was visualized using a Kesling’s diagnostic set-up. The patient accepted the orthodontic treatment plan, which began with an upper and lower fixed preadjusted edgewise appliance, 0.022 inch slot, MBT prescription. Riding pontics on the arch wires, using the acrylic teeth from her previous denture, were used to avoid an unesthetic edentulous appearance during the course of treatment. These riding pontics were sequentially reduced during the space closure phase. As the lateral incisors and canines were moved mesially during space closure, the buccolingual ridge width improved, as the roots of these were moved through and into the edentulous site. Principles of substitution treatment such as intrusion of lateral incisors to raise gingival margins and reduction of canine root prominence, were followed. At the end of the orthodontic phase (Fig 6), spaces
were left around the lateral incisors, more mesially than distally, to allow fabrication of zirconia crowns of bigger mesiodistal width to mimic central incisors. With this treatment plan, the bimaxillary proclination was corrected, along with closure of the anterior edentulous space with bilateral subtitutions of lateral incisors for central incisors, canines for lateral incisors, and first premolars for canines in the upper arch. In the lower arch, crowding was relieved, the midline was corrected, and the previous lower left first molar extraction space was closed with uprighting of the lower left second molar. The restorative phase involved zirconia crowns on the upper lateral incisors to mimic central incisors, reshaping and restorations on the canines to mimic lateral incisors, and reshaping of the first premolars to mimic canines (Fig 7). A mutually protected occlusal scheme with group function for excursive movements was established. Retention protocol required fixed anterior lingual-bonded retainers in both arches.
Discussion This article describes an integrated orthodontic and prosthodontic treatment option in patients who have lost one or both maxillary central incisors. In both the reports described, the patient came in with the chief concern of an unesthetic smile.
Figure 6 Postorthodontic intra- and extraoral views.
Figure 7 Postprosthetic rehabilitation intra- and extraoral views.
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C 2014 by the American College of Prosthodontists Journal of Prosthodontics 23 (2014) 509–513
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The first patient, a 13-year-old boy missing his maxillary right central incisor, reported 3-year post avulsion of the tooth. Direct prosthodontic replacement either with an FPD or implant was not possible without space opening and uprighting of adjacent teeth, as the edentulous space had almost closed due to teeth drifting since the avulsion. Hence, orthodontic treatment options of either opening the central incisor space for a prosthetic replacement or closing the space with substitution of maxillary lateral incisor for the missing central incisor were explored. The latter option was chosen, as the patient warranted orthodontic treatment in the lower arch with a premolar extraction in the lower right quadrant and in the upper arch, all factors necessary for a substitution treatment plan were optimal. In the second patient, a 28-year-old woman with both the upper central incisors missing was unhappy with her RPD, which she was using for missing upper incisors. Again a direct prosthodontic treatment plan with implants for the missing teeth was difficult if not impossible due to lack of sufficient buccolingual bone width at the site due to the long-standing edentulous history and thereby the need for bone grafting procedures. Additionally, the site involved was the esthetically sensitive upper anterior region in a patient with a high lip line. An FPD replacement was also not considered, as it would have involved preparing two adjacent healthy teeth. Since the patient also required orthodontic correction for crowding in the upper and lower arches with bimaxillary proclination and a mesially tilted lower left second molar due to a previously extracted first molar, an orthodontic treatment plan to correct the malocclusion features using the missing upper central incisor spaces along with extraction of a lower right first premolar was chosen. In the upper arch all factors necessary for a bilateral lateral incisor-central incisor and first premolar-canine substitution treatment plan were optimal and thus were executed. In both patients’ postorthodontic treatment, the upper lateral incisors required esthetic crowns to mimic central incisors, and the upper canines and first premolars required esthetic recountouring and necessary composite resin build-ups to resemble upper lateral incisors and canines, respectively, to fulfil esthetic and functional requirements. Both patients were happy with the treatment end result. In a critical evaluation of the treatment results, the authors do acknowledge the maxillary midline still being slightly “off” to the right in the first patient; however, further correction of the maxillary midline to the left would have required space necessitating interproximal reduction in the upper and lower left buccal segment teeth, which we decided against, as this could compromise the enamel health of the involved teeth. Also in the second patient, we do acknowledge that the gingival marginal
Strategies for Missing Maxillary Central Incisor
heights and zeniths of the substituted central and lateral incisors could have better enhanced the esthetics of the segment.
Conclusion In patients presenting with unilateral or bilateral missing maxillary central incisors, an orthodontic treatment plan involving space closure with substitution of adjacent teeth for the missing teeth along with prosthetic and restorative intervention fully satisfies the esthetic and functional demands of the patient.
References 1. Kokich V, Crabill K: Managing the patient with missing or malformed maxillary central incisors. Am J Orthod Dentofacial Orthop 2006;129:55-63 2. Jena AK,Singh SP, Utreja A: Orthodontic replacement of maxillary central incisors by lateral incisors: issues to be considered. Hellenic Orthodont Rev 2010;13:9-23 3. Newsome P, Owen S, Reaney D: Clinical quandaries: strategies for dealing with space closure following the loss of a central incisor. Int Dent SA 2011;13:6-10 4. Stenvik A Zachrisson BU: Orthodontic closure and transplantation in the treatment of missing anterior teeth. An overview. Endod Dent Traumatol 1993;9:45-52 5. Zachrisson BJ: Improving orthodontic results in cases with maxillary incisors missing. Am J Orthod 1978;73:274-289 6. Kokich V, Nappen D, Shapiro P: Gingival contour and clinical crown length: their effect on the esthetic appearance of maxillary anterior teeth. Am J Orthod 1984;86:89-94 7. Kokich V: Esthetics and anterior tooth position. An orthodontic perspective. Part 1: crown length. J Esthet Dent 1993;5:19-23 8. Kokich VG, Spear F: Guidelines for managing the orthodontic restorative patient. Semin Orthod 1997;3:3-20 9. Kokich VG: Esthetics and vertical tooth position:the orthodontic possibilities. Compendium Cont Ed Dent 1997;18:1225-1231 10. Monefeldt I, Zachrisson BU: Adjustment of clinical crown height by gingivectomy following orthodontic space closure. Angle Orthod 1977;47:256-64 11. Schwaninger B, Shaye R: Management of cases with upper incisors missing. Am J Orthod 1977;71:396-405 12. Tuverson DL: Orthodontic treatment using canines in place of missing maxillary lateral incisors. Am J Orthod 1970;58: 109-127 13. Ngan DC, Kharbanda OP, Darendeliler MA: Considerations in the management of transposed teeth. Aust Orthod J 2004;20:41-50 14. Asher C, Lewis DH: The integration of orthodontic and restorative procedures in cases with missing maxillary incisors. Br Dent J 1986;160:241-245 15. McNeill R, Joondeph DR: Congenitally absent maxillary lateral incisors. Treatment planning considerations. Angle Orthod 1973;43:24-29
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Professor, Department of Orthodontics, M.A. Rangoonwala Dental College & Research Center, Pune, India Reader, Department of Prosthodontics, M.A. Rangoonwala Dental College & Research Center, Pune, India 3 Senior Lecturer, Department of Orthodontics, M.A. Rangoonwala Dental College & Research Center, Pune, India 4 Reader, Department of Orthodontics, M.A. Rangoonwala Dental College & Research Center, Pune, India 5 Doctor, Private practice, Abu Dhabi, UAE 2
Keywords Missing maxillary central incisor; orthodontic management; canine substitution; lateral incisor substitution; prosthodontic rehabilitation; esthetic considerations. Correspondence Kunal Mehta, Dept. of Orthodontics, M.A. Rangoonwala Dental College & Research Center, Azam Campus, Pune 411001, India. E-mail: [email protected]
Abstract The loss of maxillary central incisors at an early age has psychological, esthetic, and functional implications. Multiple treatment options are available for replacing missing central incisors. The management demands a multidisciplinary approach involving the orthodontist, prosthodontist, and periodontist. Treatment planning requires consideration of a variety of clinical and nonclinical factors. This clinical report attempts to demonstrate different strategies for the management of unilaterally and bilaterally missing central incisors.
The authors deny any conflicts of interest. Accepted September 3, 2013 doi: 10.1111/jopr.12133
The maxillary central incisors play an important role in smile esthetics, function, and speech. One or both missing central incisors are often encountered in clinical practice in patients who have had traumatically avulsed central incisors or a germinated or fused maxillary central incisor that must be extracted.1 At times, agenesis of maxillary central incisors is also encountered.2 A missing maxillary central incisor can have psychological implications due to poor smile esthetics and improper speech and is thus indicated for replacement. There are many choices for replacement of a missing maxillary central incisor. If the tooth has been avulsed, the simplest long-term solution is reimplantation. If that is not possible, autotransplantation can be considered; however, the patient must have an arch length deficiency, so a premolar from a posterior quadrant can be transplanted to the edentulous site. A third option is maintenance of the edentulous space during childhood and adolescence and placement of a fixed partial denture (FPD) or an implant when the patient is an adult. A fourth possible solution is to close the edentulous space and substitute the ipsilateral lateral incisor for the central incisor.1 In deciding on the above treatment options, a variety of clinical and nonclinical factors, including the patient’s age and facial morphology, space available, width of lateral incisor and length of its root, size and
shape of teeth, color and morphology of canines, nature of any malocclusion and cuspal interdigitation, risk of future trauma, and the patient’s willingness to undergo complex, expensive treatment, must be considered.3,4 Factors for optimal esthetics
Mesiodistal position of the lateral incisor The maxillary lateral incisor is narrower and shorter than the central incisor. Also, the emergence profile of maxillary central incisors is generally flat on the mesial surface. This warrants the lateral incisor be moved close to the midline so an artificial crown can be made wider on the distal than on the mesial aspect for optimal esthetics.1,5 Matching the gingival margins of the maxillary anterior teeth The lateral incisor must be intruded so its gingival margin matches the usual gingival margin position of the central incisor.6-9 Additional intrusion also allows restoration of this tooth into the shape of a central incisor.1 Gingivectomy of the lateral incisor can also increase the clinical crown height.10 The
C 2014 by the American College of Prosthodontists Journal of Prosthodontics 23 (2014) 509–513
509
Strategies for Missing Maxillary Central Incisor
Gautam et al
maxillary canine must be extruded to move its gingival margin incisally to resemble the usual gingival margin position of the lateral incisor.1 Angulation of the lateral incisor When a unilateral central incisor is missing, it is helpful if the lateral incisor and adjacent central incisor are left more parallel than normal.11 In bilateral cases, both lateral incisors should be kept parallel to each other. Reshaping of the canine Recontouring and reshaping of the canine should be considered to give proper shape and size of a lateral incisor. The tip of the canine should be flat, the disto-incisal line angle should be rounded, and there should be proper mesiodistal reduction. The canine eminence on the labial surface should be reduced to make it flat.12 The lingual contour should be reduced to enhance adequate overbite and overjet and to eliminate prematurities.12 Reshaping of the first premolar The composite build-up of the buccal cusp of the first premolar may be required to provide optimum esthetics.13
1. Extraction of mandibular right first premolar to relieve the crowding in the mandibular arch 2. Mesial movement of maxillary right lateral incisor into the central incisor space and its conversion into central incisor and also lateralization of the maxillary right canine. 3. Maxillary midline correction by distal movement of maxillary left central incisor. The treatment plan was discussed with the patient with the aid of a Kesling’s diagnostic set-up. The treatment was divided into three phases: orthodontic, periodontal, and prosthetic. In the orthodontic phase, the maxillary left central incisor was moved distally to align its mesial margin with the facial midline. The maxillary right lateral incisor was moved mesially into the central incisor position and was also intruded so its gingival margin would match that of the adjacent central incisor after gingivectomy. The lower arch was leveled and aligned after right premolar extraction. At the completion of orthodontic treatment (Fig 2), the result was retained with a lingual-bonded retainer until the age of 18 years, and the commencement of the final periodontal and prosthetic phase. In the periodontal phase, gingivectomy for the maxillary lateral incisor was carried out to match its gingival margin with that of the adjacent central incisor. In the prosthetic phase the mesialized lateral incisor was restored with an all-ceramic crown to resemble the adjacent central incisor (Fig 3).
Shade matching
Clinical report 2 Care should be taken for optimum color matching between the so-called central and lateral incisors.14 Other factors for optimal static and functional occlusion such as labio-palatal position of the lateral incisor, vertical height of the lateral incisor crown, labiolingual inclination of the canines,11 posterior occlusion,12 and reshaping of the palatal cusp of the first premolar14,15 should also be evaluated and considered. It is strongly recommended that a Kesling’s diagnostic set-up be done in these cases to visualize the final occlusion and “fit” and also to quantify the above-stated modifications in pretreatment study models before proceeding with the actual clinical steps.
Clinical report 1 A 13-year-old boy reported to the orthodontic clinic with spacing in the upper anterior teeth and crowded lower dentition (Fig 1). He had a history of trauma and loss of an anterior tooth when he was 10 years old. Intraoral examination showed a missing maxillary right central incisor and mesial drifting of the maxillary left central incisor and right lateral incisor resulting in moderate anterior spacing. The maxillary dental midline was shifted to the right by 4 mm. The mandibular arch showed 6 mm crowding. The patient had Angle’s class I molar relation on both sides. Radiographic examination showed a missing maxillary right central incisor and good periodontal and periapical health of the adjacent incisors. After all treatment possibilities were considered, the following treatment plan was finalized510
A 28-year-old female patient presented with the chief compliant of being unhappy with her smile. She gave a history of previously extracted upper central incisors and was wearing an acrylic removable partial denture (RPD). On clinical examination (Fig 4) she presented with a class I molar relation on the right side and a Class II molar relation on the left side. Her lower left first molar was previously extracted with mesial migration of the lower left second molar. She had an edentulous anterior ridge due to the previously extracted central incisors, with space loss due to mesial migration of the adjacent teeth. The upper anterior arch form was flattened, with mild crowding and open bite in the left lateral incisor canine segment. Her upper left second molar was in complete buccal crossbite. She had mild spacing in the lower anteriors, with the lower right first premolar buccally blocked out. Her lower dental midline was shifted to the left. Extraorally, she had mildly protrusive lips and a straight profile. First, the possibility of replacing her missing upper central incisors with an implant prosthesis was explored but ruled out due to lack of sufficient buccolingual bone width in the edentulous segment due to the long-standing edentulous history (Fig 5). Implants in the region would have necessitated some form of bone augmentation for improving ridge width. The patient was then referred for an orthodontic opinion, and the orthodontist suggested the possibility of comprehensive orthodontic treatment, in which the anterior edentulous space could be completely closed. In the lower arch, with the extraction of the lower right first premolar, crowding and midline correction could be achieved. It was also decided to extract the
C 2014 by the American College of Prosthodontists Journal of Prosthodontics 23 (2014) 509–513
Gautam et al
Strategies for Missing Maxillary Central Incisor
Figure 1 Pretreatment intra- and extraoral views.
Figure 2 Postorthodontic intra- and extraoral views.
Figure 3 Postprosthetic rehabilitation intra- and extraoral views.
Figure 4 Pretreatment intra- and extraoral views.
C 2014 by the American College of Prosthodontists Journal of Prosthodontics 23 (2014) 509–513
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Figure 5 Pretreatment study models.
upper left third molar to allow crossbite correction in the second molar region. This possibility was visualized using a Kesling’s diagnostic set-up. The patient accepted the orthodontic treatment plan, which began with an upper and lower fixed preadjusted edgewise appliance, 0.022 inch slot, MBT prescription. Riding pontics on the arch wires, using the acrylic teeth from her previous denture, were used to avoid an unesthetic edentulous appearance during the course of treatment. These riding pontics were sequentially reduced during the space closure phase. As the lateral incisors and canines were moved mesially during space closure, the buccolingual ridge width improved, as the roots of these were moved through and into the edentulous site. Principles of substitution treatment such as intrusion of lateral incisors to raise gingival margins and reduction of canine root prominence, were followed. At the end of the orthodontic phase (Fig 6), spaces
were left around the lateral incisors, more mesially than distally, to allow fabrication of zirconia crowns of bigger mesiodistal width to mimic central incisors. With this treatment plan, the bimaxillary proclination was corrected, along with closure of the anterior edentulous space with bilateral subtitutions of lateral incisors for central incisors, canines for lateral incisors, and first premolars for canines in the upper arch. In the lower arch, crowding was relieved, the midline was corrected, and the previous lower left first molar extraction space was closed with uprighting of the lower left second molar. The restorative phase involved zirconia crowns on the upper lateral incisors to mimic central incisors, reshaping and restorations on the canines to mimic lateral incisors, and reshaping of the first premolars to mimic canines (Fig 7). A mutually protected occlusal scheme with group function for excursive movements was established. Retention protocol required fixed anterior lingual-bonded retainers in both arches.
Discussion This article describes an integrated orthodontic and prosthodontic treatment option in patients who have lost one or both maxillary central incisors. In both the reports described, the patient came in with the chief concern of an unesthetic smile.
Figure 6 Postorthodontic intra- and extraoral views.
Figure 7 Postprosthetic rehabilitation intra- and extraoral views.
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C 2014 by the American College of Prosthodontists Journal of Prosthodontics 23 (2014) 509–513
Gautam et al
The first patient, a 13-year-old boy missing his maxillary right central incisor, reported 3-year post avulsion of the tooth. Direct prosthodontic replacement either with an FPD or implant was not possible without space opening and uprighting of adjacent teeth, as the edentulous space had almost closed due to teeth drifting since the avulsion. Hence, orthodontic treatment options of either opening the central incisor space for a prosthetic replacement or closing the space with substitution of maxillary lateral incisor for the missing central incisor were explored. The latter option was chosen, as the patient warranted orthodontic treatment in the lower arch with a premolar extraction in the lower right quadrant and in the upper arch, all factors necessary for a substitution treatment plan were optimal. In the second patient, a 28-year-old woman with both the upper central incisors missing was unhappy with her RPD, which she was using for missing upper incisors. Again a direct prosthodontic treatment plan with implants for the missing teeth was difficult if not impossible due to lack of sufficient buccolingual bone width at the site due to the long-standing edentulous history and thereby the need for bone grafting procedures. Additionally, the site involved was the esthetically sensitive upper anterior region in a patient with a high lip line. An FPD replacement was also not considered, as it would have involved preparing two adjacent healthy teeth. Since the patient also required orthodontic correction for crowding in the upper and lower arches with bimaxillary proclination and a mesially tilted lower left second molar due to a previously extracted first molar, an orthodontic treatment plan to correct the malocclusion features using the missing upper central incisor spaces along with extraction of a lower right first premolar was chosen. In the upper arch all factors necessary for a bilateral lateral incisor-central incisor and first premolar-canine substitution treatment plan were optimal and thus were executed. In both patients’ postorthodontic treatment, the upper lateral incisors required esthetic crowns to mimic central incisors, and the upper canines and first premolars required esthetic recountouring and necessary composite resin build-ups to resemble upper lateral incisors and canines, respectively, to fulfil esthetic and functional requirements. Both patients were happy with the treatment end result. In a critical evaluation of the treatment results, the authors do acknowledge the maxillary midline still being slightly “off” to the right in the first patient; however, further correction of the maxillary midline to the left would have required space necessitating interproximal reduction in the upper and lower left buccal segment teeth, which we decided against, as this could compromise the enamel health of the involved teeth. Also in the second patient, we do acknowledge that the gingival marginal
Strategies for Missing Maxillary Central Incisor
heights and zeniths of the substituted central and lateral incisors could have better enhanced the esthetics of the segment.
Conclusion In patients presenting with unilateral or bilateral missing maxillary central incisors, an orthodontic treatment plan involving space closure with substitution of adjacent teeth for the missing teeth along with prosthetic and restorative intervention fully satisfies the esthetic and functional demands of the patient.
References 1. Kokich V, Crabill K: Managing the patient with missing or malformed maxillary central incisors. Am J Orthod Dentofacial Orthop 2006;129:55-63 2. Jena AK,Singh SP, Utreja A: Orthodontic replacement of maxillary central incisors by lateral incisors: issues to be considered. Hellenic Orthodont Rev 2010;13:9-23 3. Newsome P, Owen S, Reaney D: Clinical quandaries: strategies for dealing with space closure following the loss of a central incisor. Int Dent SA 2011;13:6-10 4. Stenvik A Zachrisson BU: Orthodontic closure and transplantation in the treatment of missing anterior teeth. An overview. Endod Dent Traumatol 1993;9:45-52 5. Zachrisson BJ: Improving orthodontic results in cases with maxillary incisors missing. Am J Orthod 1978;73:274-289 6. Kokich V, Nappen D, Shapiro P: Gingival contour and clinical crown length: their effect on the esthetic appearance of maxillary anterior teeth. Am J Orthod 1984;86:89-94 7. Kokich V: Esthetics and anterior tooth position. An orthodontic perspective. Part 1: crown length. J Esthet Dent 1993;5:19-23 8. Kokich VG, Spear F: Guidelines for managing the orthodontic restorative patient. Semin Orthod 1997;3:3-20 9. Kokich VG: Esthetics and vertical tooth position:the orthodontic possibilities. Compendium Cont Ed Dent 1997;18:1225-1231 10. Monefeldt I, Zachrisson BU: Adjustment of clinical crown height by gingivectomy following orthodontic space closure. Angle Orthod 1977;47:256-64 11. Schwaninger B, Shaye R: Management of cases with upper incisors missing. Am J Orthod 1977;71:396-405 12. Tuverson DL: Orthodontic treatment using canines in place of missing maxillary lateral incisors. Am J Orthod 1970;58: 109-127 13. Ngan DC, Kharbanda OP, Darendeliler MA: Considerations in the management of transposed teeth. Aust Orthod J 2004;20:41-50 14. Asher C, Lewis DH: The integration of orthodontic and restorative procedures in cases with missing maxillary incisors. Br Dent J 1986;160:241-245 15. McNeill R, Joondeph DR: Congenitally absent maxillary lateral incisors. Treatment planning considerations. Angle Orthod 1973;43:24-29
C 2014 by the American College of Prosthodontists Journal of Prosthodontics 23 (2014) 509–513
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