Congenitally missing maxillary lateral incisors:

Restorative replacementCOUNTERPOINT

Vincent O. Kokich, Jr.Greggory A. Kinzer, and

Jim Janakievski

AJO DO April 2011, Vol 139, Issue 4

Introduction

• The maxillary lateral incisor is the second most frequently missing tooth in the dental arch with clinical management requiring a complex and multidisciplinary treatment approach is required

The esthetic and functional success of canine substitution ultimately depends on variables such as malocclusion, crowding, profile, crown shape and color, and smiling lip level

INDICATION

Those patients who do not meet the specific qualifications necessary to be considered optimal candidates for canine substitution, an alternative form of treatment must be considered.

Restorative treatment alternatives

Single tooth

implant

Tooth-supported restoration

Resin bondedfixed partial

dentureCantilevered

FPD

Conventional full-coverage

FPD

IMPLANT-SUPPORTED RESTORATIONS

• The single-tooth implant has become the most popular treatment alternative for the replacement of missing teeth

• The main benefit of this type of restoration is that it leaves the adjacent teeth untouched. This is particularly important in young patients and unrestored dentitions.

Implant-site development

• After implant placement, dimensional changes in the surrounding crestal bone occur in both vertical and horizontal dimensions.

• If an implant is to be used to replace a missing lateral incisor, the thickness of the alveolus must be adequate to allow for proper implant placement.

• As the osseous ridge in this area is typically deficient due to absent of maxillary lateral incisor.

• the permanent canine is allowed to erupt mesially through the alveolus into the lateral incisor position, its large buccolingual width willinfluence the thickness of the edentulous ridge.

• Then,after the permanent canine is orthodontically moved distally, an increased buccolingual alveolar width is established

If it fails .

• Positioning dental implants in a narrow ridge will require deeper placement to prevent a bony dehiscence and also results in a thin layer of bone on the facial aspect, both of which will have a negative impact on the surrounding soft tissues.

This may lead to

The biologic width or bone remodeling of the thin buccal bone will inevitably lead to show-through of both the implant body and the abutment, resulting in an unesthetic cyanotic color of the soft tissue, gingival recession, and abutment exposure.

Unilateral agenesis of the maxillary left lateral incisor with a peg-shaped right lateral incisor in an 18-year-old woman. The patient had just completed orthodontic treatment. Moderate-to-advanced facial ridge resorption was present in the maxillary left lateral incisor site with gingival asymmetry noted betweenThe maxillary right lateral and the 2 central incisors (altered passive eruption). Rather than rebracket, it wasdecided to restore the maxillary left lateral incisor site with a single-tooth implant with guided bone regeneration and perform esthetic crown lengthening on the facial aspects of the 2 right central and lateralincisors to match the free gingival margin locations of the contra-lateral teeth. The final result looksnatural with regard to tooth position, gingival margin symmetry, papillae location, and tissue color

• It is seen that the loss of the supporting bone is worse if the implant-to tooth distance is less than 1.5 mm. This results in apical migration of the papillary tissue, leading to open gingival embrasures and lack of gingival scallop.30 Mesio-distally, most lateral incisor sites will be between 5 and 7 mm. Historically, because of the lack of options regarding implant sizes, the use of standard diameter 3.75- to 4.0-mm implants was common in implant therapy. This compromise in proximal implant positioning led to unfavorable esthetic outcomes

A word before de-bonding

• After the appropriate amount of coronal space has been determined, it is necessary to evaluate the interradicular spacing.36 Inadequate space between the root apices is generally due to improper root angulation. Therefore, it is important to take a periapical radiograph of the edentulous area before removing the orthodontic appliances to confirm the ideal root position and adequate spacing for future implant placement.

BUT

Implants however, cannot be placed until facial growth is complete. Therefore, monitoring the eruption in these patients at an early age is important for optimal implant-site development

Timing of implant placement

• The appropriate time to place an implant is based on a patient’s facial growth. As the face grows and the mandibular rami lengthen, the teeth must erupt to remain in occlusion. Implants cannot erupt. If an implant is placed before a patient has completed his or her facial growth, significant periodontal, occlusal, and esthetic problems can be created

• The timing for implant placement after the end of growth is generally about 20 to 21 years of age for men and 16 to 17 years of age for girls

Interim tooth replacement after orthodontics

• It is done If implants cannot be placed until facial growth is complete, the edentulous space must be maintained after the orthodontic appliances are removed until the implant can be placed and restored.

Solution

• A removable retainer with a prosthetic tooth is an easy and efficient way to replace the missing tooth as well as to ensure post-orthodontic retention.

• If there is long duration before growth is completed, it is possible to see the roots of the central incisor and canine converge toward each other during the retention phase, making future implant placement difficult or impossible. Therefore, a more appropriate choice might be a bonded fixed retainer. This could be as simple as a traditional lingual wire with a prosthetic tooth or as involved as a laboratory-fabricated resin-bonded FPD.

• According to author regardless of the choice, these long-term retainers are excellent for maintaining the final orthodontic position of the canine and the central incisor.

TOOTH-SUPPORTED RESTORATIONS

• The most conservative tooth-supported restoration is the resin-bonded FPD, because it leaves the adjacent teeth relatively untouched. It has been seen that the success rate of this type of restoration varies widely, with debonding the most common cause of failure

CRITERIA FOR TOOTH-SUPPORTED RESTORATIONS

• These criteria include the position and mobility of the abutment teeth as well as the overall occlusion. If any of these criteria are not met, the predictability of the final restoration will be compromised

• Ideal anterior relationship is a shallow overbite

• Mobility of the abutment teeth is also a contraindication for resin-bonded FPDs because it impacts the durability of the bond in 2 ways.

• “Directional” mobility problems arise with lateral incisor replacement since a mobile central incisor and a mobile canine move in different vectors because of their positions in the arch. This places increased stress at the bond interface.

• “Differential” mobility is when the abutment teeth have different grades of mobility. Generally, it is the least mobile of the 2 abutments that will debond because the restoration tends to move with more mobile abutment

IDEAL CANDIDATE FOR TOOTH-SUPPORTED RESTORATIONS

• Non-bruxer with abutment teeth that are immobile

• Upright with a shallow overbite

Cantilevered FPD

• A more predictable tooth-supported restoration that overcomes the limitations of a conventional resin bonded FPD is the cantilevered FPD

• As compared with the resin-bonded FPD, the success of this restoration does not depend on the amount of proclination or mobility of the abutment teeth. If the facial esthetics of the canine abutment do not need to be altered, the most conservative cantilevered restoration uses a partial coverage preparation

• The key to the long-term success of a cantilevered bridge restoration is managing the occlusion on the pontic.

• All contact in excursive movements must be removed from the cantilever. If eccentric contact remains on the pontic, the potential risks include loosening of the restoration, migration of the abutment, and fracture.

Conventional full-coverage FPD

• The least conservative of all tooth-supported restorations is a conventional full-coverage FPD. This restoration is generally considered the treatment of choice only when replacing an existing full-coverage bridge or the adjacent teeth require restoration for structural reasons such as caries or fracture. However, because of the amount of tooth preparation required for a conventional bridge restoration, it is not the ideal treatment for replacement of missing lateral incisors in young patients.

CONCLUSIONS

• There are several restorative options for the replacement of congenitally missing lateral incisors, including resin-bonded bridge, cantilevered bridge, and conventional full-coverage bridge. Each of these restorative

options has a high degree of success if used in the correct situation

CONCLUSIONS

• The main advantage of this type of restoration is conservation of tooth structure. It leaves

the adjacent teeth intact. The orthodontist’s role is to provide the coronal and apical spacing necessary to facilitate any future restorative dentistry and implant placement

Review of litrature

• IMPLANT REPLACEMENT OF CONGENITALLY MISSING LATERAL INCISORS: A CASE REPORT

Sheldon Winkler, DDS; Kenneth G. Boberick, DMD; Stanton Braid, DDS; Robert Wood, DDS; Michael J. Cari, DMD Journal of oral implantology Vol.XXXIV/No. Two/2008

• Implants can readily be placed and restored in congenitally missing maxillary lateral incisor sites with predictable results if surgical, periodontal, and prosthodontic conditions are favorable. A case report using dental implants to replace bilateral congenitally absent maxillary lateral incisors for teenage female identical twins is presented.

Conclusion• The best treatment for replacement of congenitally missing maxillary

lateral incisors is the most conservative approach that meets esthetic and functional demands. Implants do not require preparation of natural teeth, promote alveolar ridge preservation, and can facilitate achieving optimum restorative results.

• Implant treatment planning in the case of congenitally missing maxillary lateral incisors depends on occlusion, anterior relationships, space requirements, and the condition of the adjacent teeth. Possible problems include space limitations for implant placement and prosthodontic restoration, close proximity of the apices of adjacent teeth to the proposed implant site, inadequate ridge thickness that requires augmentation, and inadequate bone support for the gingival papillae

• If implants are inserted and restored at too early age, the adjacent teeth can erupt and create disharmony between the gingival margins of the implant and the natural teeth. Kokich has recommends waiting until an adolescent male has completed growth in height. For a female, facial growth is often completed by 15 to 16 years of age. Implants can be placed earlier in females as compared with males without the risk of adjacent teeth eruption

• Congenitally missing teeth:Orthodontic management in the adolescent patient

Vincent O. Kokich, Jr, DMD, MSD

In opening space, the main concern is alveolar ridge width in the area of the missing lateral incisor. Alveolar ridge width may be influenced in the mixed dentition during the eruption of the permanent canine. The idealsituation is to encourage the canine to erupt adjacent to the permanent central incisor. After the canine has erupted, it can be moved distally into its normal position. By moving the tooth distally, bone is laiddown, forming an alveolar ridge with adequate buccolingual width to facilitate proper implant placement. Occasionally, the canine does not erupt adjacent to the central incisor. When this occurs, a future bone graftmight be necessary to establish the appropriate width in the edentulous area to place an implant

Conclusion

• Orthodontists commonly encounter patients with congenitally missing maxillary lateral incisors. Treatment decisions must be based on eruption pattern, age, gender, and presence of a permanent tooth. If the patient is missing the maxillary lateral incisors, guided eruption and ridge development are critical. Therefore, monitoring these patients in the mixed dentition is essential to preserve various treatment options in the future

• Temporarily replacing congenitally missing maxillary lateral incisors in teenagers using transitional Implants-Implant News & Views January/February 2001 Vol. 3 No. 1

Dr. G. William Keller

• As a transition, the removable appliance is the first choice amongst orthodontists. Not only does it replace the missing teeth, but also functions as an orthodontic retainer. Orthodontic retention is very important post active therapy for at least 9-12 months in which the patient wears the retainer 24 hours a day to allow for proper bone remodeling.

• The inconvenience of this appliance is quite obvious, especially when eating and talking. The social embarrassment of showing “no teeth” when eating in front of their friends can be quite disturbing

• Transitional Implants .A unique approach involves the use of transitional implants that are normally utilized to support partially and/or fully edentulous provisional restorations and have been widely discussed and documented in the literature. Using these fixtures to retain a provisional restoration in a single tooth gap created by congenitally missing laterals in a teenager

The treatment plan coordinates the surgical,restorative and laboratory procedures sothat the provisional restoration can beplaced within 24 hours after MTI placement[Modular Transitional Implants

Once adequate anesthesia hasbeen achieved, the osteotomies are performedin the edentulous sites createdby the congenitally missing teeth. In most cases, the osteotomy is done without incisions or the use of a surgical flap. This is accomplished quite easily with the use of the pointed [long] 1.3 mm diameter profile twist drill. It is important to be parallel to the palatal taper due to the presence of labial concavities.Insert the MTI fixture manually or with the implant handpiece adapter. Due to the approximate 3 mm of transmucosal distance from theosseous crest, you must account for this when drilling the osteotomy. Once the MTI fixture is placed to the pre-determined depth, besure the slot on the fixture is in a mesial/distal direction to accommodate the restorative component. The fixture can then be bent to the ideal position for restorative purposes

• Clinical Case Report: An Interdisciplinary Approach for Congenitally Missing Maxillary Lateral Incisors

Norman W. Ickert,;Perry H. Beeson Jr,; and Kimberly L. Gragg, Journal of Functional Esthetics & Restorative Dentistry

• The patient's main concerns were that her teeth were not properly aligned, two upper lateral incisors were missing, and the canines in the lateral incisor were not present the proper appearance. She said it was important to have "normal“ lateral incisors

• PROGNOSIS The prognosis for this dentition was considered good

but was highly dependent on the successful achievement of the orthodontic treatment to place the teeth In acceptable occlusion and to provide enough space for the placement of implants the maxillary lateral spaces. In addition, the prognosis depended on the placement of implants in adquate and management of the hard and soft tissue for the patients esthetic demands.

Conclusion• This interdisciplinary approach necessitated a treatment-planning process that started with the

final outcome in mind. The incisai edge position, occlusion plane, orthopedic position, and esthetic factors were anticipated and planned from the start.

• Respecting the five keys to esthetic success for implants in the esthetic zone and anticipating potential hard- and soft-tissue variables and how to address them during the surgical and prosthetic phases, assured the greatest likelihood for success, both in the short and long term. The detailed orthodontic placement of the teeth in the arch and with adequate interroot space for implant placement was equally important. Ideal esthetics requires ideal tooth position.

• Although there can be only one correct diagnosis, various treatment options are possible, each with a different long-term prognosis. Surgically, other treatment modalities for splitting and expanding the ridge could have been the use of Piezosurgery“ (Mectron s.p.a, Carasco, Italy) or a scalpel blade,. Prosthetically, lab selected customized-machined and contoured abutments (ANKYLOS Balanced Abutment System, DENTSPLY Friadent Ceramed) also could have been selected. The approach used for this patient, witb missing and improperly aligned teeth, illustrates tlhe rationale ; execution of an interdisciplinary treatment plan treatment illustrate the management of the patients Rinctional, esthetic, iuid psychological needs in a relatively noninvasive and long-term predictable manner. The results were very acceptable to the patient and exceeded her expectations

• Planning esthetic treatment after avulsion of maxillary incisors- Björn U Zachrisson INTERNATIONAL DENTISTRY SA VOL. 12, NO. 2

• When a young patient accidentally loses two neighboring maxillary incisors, the choice of treatment plan is difficult. Although implant restorations are a popular option, they cannot be placed until skeletal growth is finished.

• Furthermore, the use of two neighboring implant crowns represents a considerable challenge from an esthetic point of view.This case report describes an innovative solution that combined autotransplantation of a developing premolar andorthodontic space closure

Frontal facial view of 11-year-old patient who had lost bothThe maxillary right lateral incisor and the maxillary right central incisor in an accident

The developing mandibular right second premolar wasautotransplanted to the injury site. Note immature root development ofmandibular second premolarswith open apex

Autotransplanted premolar tooth in position. Note mesial drift and excessive lingual crown inclination of maxillary canines and premolars, constricting the smile.

After restoration with resin-based composite buildup on the transplanted premolar, orthodontic treatment was begun with super elastic levelingwire

Orthodontic treatment result. It is noted upright canines and posterior teeth to broaden the smile. The deep bite and midline are slightly overcorrected. The right canine crown fracture is apparent.

Three porcelain veneers are placed on the “new” canine, lateralincisor and central incisor.

The treatment result was maintained with an .0215-inch gold coated wireretainer bonded lingually to six teeth

Higher magnification of the three teeth provided with veneers natural tooth morphology and normal gingival condition