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Unilateral agenesis of the maxillary lateral incisor: space closure versus space preservation in growing patients

Open AccessPublished:February 21, 2020DOI:https://doi.org/10.1053/j.sodo.2020.01.004

      Abstract

      A unilateral congenitally missing maxillary lateral incisor is often associated with a small or peg-shaped contralateral tooth. This form of hypodontia is also frequently combined with a generally undersized maxillary dentition, which could therefore be considered a paradigm for esthetic situations where problems of tooth position, size and form need to be connected and resolved. The space opening versus the space closure option should derive from a hierarchy of decisions. When we treat young patients, the restorative solutions should be obtained by a minimally invasive approach, which facilitates both the reversibility and ease of reintervention in the long term.

      Introduction

      Agenesis of anterior teeth in growing patients is one of the most challenging situations in the dental practice. We often complete our orthodontic treatment in adolescent patients who still undergo significant changes and present an unstable ground for a long lasting restorative solution. The key issue is to provide these teenage patients with a satisfactory esthetic and functional outcome for the long transition from adolescence into adulthood.
      Unilateral agenesis of an upper lateral incisor often occurs with a small or peg-shaped contralateral incisor.
      • Brook A.H.
      Variables and criteria in prevalence studies of dental anomalies of number, form and size.
      A missing or peg-shaped lateral incisor is a significant determining factor for an overall reduction of the mesiodistal tooth widths in the affected quadrant, with the maxillary central incisors exhibiting the greatest reduction in size.
      • Mirabella A.D.
      • Kokich V.G.
      • Rosa M.
      Analysis of crown widths in subjects with congenitally missing maxillary lateral incisors.
      ,
      • Bozkaya E.
      • Canigur Bavbek N.
      • Ulasan B.
      New perspective for evaluation of tooth widths in patients with missing or peg-shaped maxillary lateral incisors: Quadrant analysis.
      This form of hypodontia can be used as a paradigm to describe the hierarchy of decisions and interactions for ortho-prosthodontic treatments in the esthetic zone. The decision of space opening or space closing is the result of a logical sequence of considerations. 3D digital planning and the use of temporary anchorage devices (TADs) can help to increase the predictability of the intended outcome. The interdisciplinary solution should provide a pleasing esthetic outcome, periodontal health, and long-term stability.

      Possible orthodontic solutions

      The orthodontist has to choose among 3 solutions:
      • 1.
        Extraction of the small lateral incisor, symmetrical space closure with bilateral canine substitution,
      • 2.
        Unilateral space closure in combination with restorative therapy for the dental asymmetry, or
      • 3.
        Space opening for a prosthetic replacement of the missing lateral with subsequent equal enlargement of both lateral incisors.
      A 3D virtual set-up can be helpful to plan the best final occlusion by establishing the most favorable position of the teeth which need to be restored. The position and size of teeth should be planned before defining their final form (Figs. 25).

      Extraction of the upper lateral incisor and bilateral space closure

      The bilateral space closure solution with canine substitution provides satisfactory esthetic and functional long term results, and can be considered a feasible option already during adolescence.
      • Tuverson D.L.
      Orthodontic treatment using canines in place of missing maxillary lateral incisors.
      • Thordarson A.
      • Zachrisson B.U.
      • Mjor I.A.
      Remodeling of canines to the shape of lateral incisors by grinding: a long-term clinical and radiographic evaluation.
      • Robertsson S.
      • Mohlin B.
      The congenitally missing upper lateral incisor. A retrospective study of orthodontic space closure versus restorative treatment.
      • Zachrisson B.
      • Rosa M.
      • Toreskog S.
      Congenitally missing maxillary lateral incisors: canine substitution.
      The possibility to restore the 6 anterior teeth with minimally invasive preparation (MIP) can resolve the frequently concomitant presence of small teeth related to this form of hypodontia (Fig. 3).
      Healthier periodontal conditions after space closure have been reported,
      • Brough E.
      • Donaldson A.N.
      • Nain F.B.
      Canine substitution for missing maxillary lateral incisors: the influence of canine morphology, size, and shade on perceptions of smile attractiveness.
      • Rosa M.
      • Zachrisson B.U.
      Integrating space closure and esthetic dentistry in patients with missing maxillary lateral incisors.
      • Rosa M.
      • Lucchi P.
      • Ferrari S.
      • Zachrisson B.U.
      • Caprioglio A.
      Congenitally missing maxillary lateral incisors: Long-term periodontal and functional evaluation after orthodontic space closure with first premolar intrusion and canine extrusion.
      and the esthetic results are judged more favorably by lay people than any prosthodontic replacement.
      • Kokich V.G.
      • Spear F.M.
      Guidelines for managing the orthodontic-restorative patient.
      Extraction of the upper lateral and canine substitution is a consequence of 3 occlusal conditions:

      Extractions of lower bicuspids

      If the orthodontist recognizes the indication for extractions in the lower arch to resolve excessive crowding or protrusion, coordination of the reduced lower tooth material with the upper dentition will make extraction of the contralateral upper lateral incisor and subsequent symmetrical space closure by canine substitution almost inevitable (Fig. 1).
      Figure 1
      Figure 1Female patient age 15,5 years. The maxillary right upper lateral incisor is congenitally missing. Anterior and posterior lower crowding and incisor protrusion lead to the decision to extract 2 lower second bicuspids and, consequently, to extract the small upper left lateral incisor for bilateral space closure.
      Figure 2
      Figure 23D Digital set up. Lower arch: extraction of second bicuspids and space closure with minimum anchorage (3Shape®, Ortho Analyzer). Space closure in the upper arch and cuspids substitution; evaluation of position and size of future restorations (Digital Smile Design, DSD).
      Figure 3
      Figure 3Bilateral space closure and cuspids substitution. Composite restorations for upper centrals, ultra thin feldspathic veneers (Minimally Invasive Preparation, MIP) for laterals and cuspids. (Restorative dentist: M. Veneziani).
      Figure 4
      Figure 4Congenitally missing upper left lateral incisor. Hypodontia will small teeth. Spaced upper arch. Upper and lower midilines deviated to the left. Dental asymmetry in the lower arch. Lower left cuspid and molar are more posteriorly placed. The distalization of the upper left cuspid and the space opening option are deemed less predictable.
      In this case, the orthodontist needs to control the anchorage in the lower arch to avoid excessive incisor retraction.

      Retraction of the upper incisors

      In Class 2 malocclusions, where the upper incisors need to be retracted for correction of the increased overjet, controlling the upper midline requires symmetrical space closure and cuspid substitution after extraction of the upper lateral.
      The feasibility of this orthodontic camouflage must take the potential reduction of the upper lip support and/or excessive projection of the nose into consideration.

      Upper crowding and upper midline deviation

      The amount of both maxillary crowding and upper midline deviation towards the affected side requires a thorough space analysis of the 2 upper quadrants.
      This quadrant analysis should also take the presence of smaller teeth and the required space for their restorations into account (Fig. 5).
      Figure 5
      Figure 5DSD to digitally evaluate dental position and size. Space opening in the upper left quadrant should be of at least 7.5-8 mm to allow 6.5 mm for implant placement and the enlargement of the upper front teeth. Space closure on the left side by canine substitution as the most predictable solution, because of the more posterior position of the lower canine on this side (subdivision).
      If the quadrant with the congenitally missing lateral incisor exhibits severe lack of space for its prosthetic replacement, and the upper midline needs to be centered, the extraction of the contralateral upper lateral followed by bilateral space closure and canine substitution offers the most predictable result.
      The extraction of the controlateral upper lateral can be considered a consequence of morphologic conditions:
      • Kokich V.G.
      • Spear F.M.
      Guidelines for managing the orthodontic-restorative patient.

      Peg-shaped upper lateral incisor

      The extraction of the upper lateral incisor can be considered, if crown form, root morphology, or lack of gingival support makes its restoration very difficult or impossible to create a perfect match with the contralateral mesialized canine.
      Bilateral or unilateral space closure often requires significant mesialization of the upper posterior buccal segments. These orthodontic movements can be facilitated by the use of TADs.
      • Wilmes B.
      • Vasudavan S.
      • Drescher D.
      Maxillary molar mesialization with the use of palatal mini-implants for direct anchorage in adolescent patients.
      Utmost attention should be given to intrusion of the upper first bicuspids and extrusion of the cuspids for harmonizing their gingival contours as described by Rosa and Zachrisson.
      • Rosa M.
      • Zachrisson B.U.
      Integrating space closure and esthetic dentistry in patients with missing maxillary lateral incisors.
      ,
      • Kokich Jr, V.O.
      • Kinzer G.A.
      • Janakievski J.
      Congenitally missing maxillary lateral incisors: restorative replacement.
      ,
      • Rosa M.
      • Lucchi P.
      • Ferrari
      • et al.
      Congenitally missing maxillary lateral incisors: Long-term periodontal and functional evaluation after orthodontic space closure with first premolar intrusion and canine extrusion.
      During the orthodontic finishing phase, the restorative dentist should direct the final position of the 6 upper anterior teeth in order to achieve the best restorative result with minimal invasive preparation (MIP) or with no preparation at all. The increased size of the 6 anterior restorations helps to reduce the risk of space reopening in the long term.

      Unilateral space closure maintaining the small lateral incisor: a restorative challenge

      The upper lateral incisor may be maintained when its quadrant is (or is almost) in a Class 1 relationship and the aforementioned indications for bilateral space closure are not present. In this case, the decision to open or to close the controlateral space will be based on the predictability of the distal or mesial orthodontic movement of the correspondent buccal segment.
      Great attention needs to be paid to the presence of a possible subdivision due to either a mandibular dental and/or skeletal asymmetry.
      • Alavi D.G.
      • BeGole E.A.
      • Schneider B.J.
      Facial and dental arch asymmetries in Class II subdivision malocclusion.
      ,
      • Azevedo A.R.
      • Janson G.
      • Henriques J.F.
      • et al.
      Evaluation of asymmetries between subjects with Class II subdivision and apparent facial asymmetry and those with normal occlusion.
      If a lower dental asymmetry with a more posterior position of the canine and the molar is present on the same side as the upper agenesis, space closure and cuspid substitution is the preferred choice.
      The use of palatal TADs can facilitate the mesialization of the posterior segment.
      • Wilmes B.
      • Vasudavan S.
      • Drescher D.
      Maxillary molar mesialization with the use of palatal mini-implants for direct anchorage in adolescent patients.
      In case of an overall undersized maxillary dentition, a 3D digital set-up can be helpful for defining the adequate final tooth size. Temporary composite restorations or CAD-CAM veneers – already performed at the beginning of treatment- allow the orthodontist to work with the correct size of teeth from day 1 (Fig. 6).
      Figure 6
      Figure 6Unilateral space closure. The upper front teeth have been enlarged with provisional composite restorations, placed before orthodontic treatment according to the digital plan, to achieve the desired final tooth position. Definitive feldspathic MIP veneers. (Restorative dentist: M. Veneziani).
      If the upper midline results mildly deviated due to the asymmetrical lower arch, this situation should be managed as previously described by Vince Kokich jr. to make it esthetically acceptable.
      • Alavi D.G.
      • BeGole E.A.
      • Schneider B.J.
      Facial and dental arch asymmetries in Class II subdivision malocclusion.
      The final orthodontic position should make MIP restorations of the upper front teeth possible. A slightly retrusive position of the canine helps to reduce its dominance and facilitates restorative cuspid-lateral substitution (Fig. 6).
      On the contrary, distalization and space opening can be very demanding and unpredictable in a subdivision malocclusion, if attempted on the same side as the more posterior mandibular dentition. Vice versa, space opening could be a feasible option, if planned on the side where the lower cuspid and molar are more anterior (Fig. 7).
      Figure 7
      Figure 7Congenitally missing upper left lateral incisor. Spaced upper arch. Upper midilines deviated to the left. Dental asymmetry in the lower arch. Lower right cuspid and molar are positioned more posteriorly. Distalization of the upper left canine and space opening for prosthetic replacement of the missing lateral incisor is a feasible option.

      Space opening and molar distalization

      If the lack of space in the maxillary quadrant affected by agenesis is not severe and the contralateral quadrant is almost in Class 1 occlusion, space opening for prosthetic replacement of the missing tooth can be considered. It is definitely the first option in presence of a spaced upper arch.
      If a full Class 2 relationship is present on the affected side, achieving Class 1 occlusion and obtaining adequate space for prosthetic replacement of the missing lateral incisor by distalization of the entire hemiarch is less predictable.
      It has been reported, that when the canine has erupted mesially, its distalization can increase the buccolingual alveolar width,
      • Azevedo A.R.
      • Janson G.
      • Henriques J.F.
      • et al.
      Evaluation of asymmetries between subjects with Class II subdivision and apparent facial asymmetry and those with normal occlusion.
      which will remain stable over time,
      • Kokich V.O.
      • Kokich V.G.
      • Kiyak H.A.
      Perception of dental professionals and laypersons to altered dental esthetics: Asymmetric and symmetric situations.
      and that distalization can be facilitated by TADs and corticotomies.
      • Aboul-Ela S.M.
      • El-Beialy A.R.
      • El-Sayed K.M.
      • et al.
      Miniscrew implant-supported maxillary canine retraction with and without corticotomy-facilitated orthodontics.
      ,
      • Long H.
      • Pyakurel U.
      • Wang Y.
      • et al.
      Interventions for accelerating orthodontic tooth movement: a systematic review.
      A mini-implant anchored pontic can be used to control the upper midline and to facilitate space opening. (Fig. 8) This type of pontic can also serve as a temporary solution to allow vertical growth of the alveolar process over a period of 5 years.
      • Ciarlantini R.
      • Melsen B.
      Semipermanent replacement of missing maxillary lateral incisors by mini-implant retained pontics: A follow-up study.
      However, a developing convergence of the adjacent roots over time might still pose a problem for future implant placement.
      • Olsen T.M.
      • Kokich Jr, V.G.
      Postorthodontic root approximation after opening space for maxillary lateral incisor implants.
      Figure 8
      Figure 8Palatal mini-implants (Benefit® 2.3 × 9 mm implants, PSM Germany) have been used to distalize both quadrants for creating the appropriate space for upper anterior restorations and prosthetic replacement of the congenitally missing left lateral incisor. A provisional anchored to the mini implants facilitated both management of the upper midline and space distribution for the 1-wing ovate pontic.

      Space requiremets for a single tooth implant or a resin bonded FDP

      Prosthodontic substitution of the missing lateral incisor can be performed by insertion of either a single tooth implant or a fixed dental protheis (FDP), in particular a resin bonded cantilever bridge.

      Single tooth implant

      A single tooth implant is often preferred by dentists because it leaves the adjacent teeth untouched.
      • Schneider U.
      • Moser L.
      • Fornasetti M.
      • et al.
      Esthetic evaluation of implants vs canine substitution in patients with congenitally missing maxillary lateral incisors: Are there any new insights?.
      This approach requires intercoronal and interradicular space opening of at least 6-6,5 mm.
      • Tarnow D.P.
      • Cho S.C.
      • Wallace S.S.
      The effect of inter-implant distance on the height of the inter-implant bone crest.
      The same space is necessary for the enlargement of the upper small lateral in the contralateral quadrant.
      Since this form of hypodontia is often associated with the presence of generally small teeth, the space could be insufficient for correct implant placement after distalizing the cuspid into Class 1, if the original deficient dental dimensions are maintained.
      Conversely, if the space requirement for the upper lateral implant is 6.5 mm, the upper centrals need to be at least 8.5 - 9 mm wide for adequate achieving tooth proportions; hence, when the upper central incisors are small, the orthodontist should plan to open some extra space for their enlargement, creating a total space of 7.5 - 8 mm (Fig. 5). A thorough space analysis of the upper quadrants is mandatory in order to assess these prosthetic and restorative requirements.

      Bonded FDP

      If the choice is to maintain the smaller size of the maxillary teeth, a resin-bonded FDP can be an alternative to a single tooth implant-borne crown. In this case, even a 5 mm space for the missing upper lateral is adequate.
      • Kern M.
      RBFDPs - Resin-Bonded Fixed Dental Prostheses Minimally invasive - esthetic – reliable.
      The smaller the space, the more favorable the biomechanical performance of a 1- wing pontic will be, and only minimal or even no preparation is needed.
      1-wing FDPs can overcome some of the instability problems which had been encountered in a 2-wing design,
      • Kern M.
      Clinical long-term survival of two-retainer and single-retainer all-ceramic resin-bonded fixed partial dentures.
      especially in patients with a deep bite or proclined upper incisors.
      Directional mobility problems are reduced by a 1-wing design with better long-term prognosis.
      • Sailer I.
      • Bonani T.
      • Brodbeck U.
      • et al.
      Retrospective clinical study of single-retainer cantilever anterior and posterior glass-ceramic resin-bonded fixed dental prostheses at a mean follow-up of 6 years.
      To date, the best choice for a resin-bonded bridge is a 2-unit (1 wing) instead of 3-unit (2 wings) design, because of its reduced risk of secondary caries.
      • Kern M.
      • Passia N.
      • Sasse M.
      • et al.
      Ten-year outcome of zirconia ceramic cantilever resin-bonded fixed dental prostheses and the influence of the reasons for missing incisors.
      Important parameters affecting long-term prognosis of the 1-wing cantilever bridge are the choice of the material, the bonding surface, the bonding technique, and the thickness of the connector.
      • Kern M.
      RBFDPs - Resin-Bonded Fixed Dental Prostheses Minimally invasive - esthetic – reliable.
      Adding a 0.5 mm layer of composite material to the palatal surface of the central incisor or the cuspid (where the wing will be bonded) already during the orthodontic leveling phase reduces the amount of necessary enamel preparation for the wing by the prosthodontist.
      The standard materials for resin-bonded bridges are either zirconia or lithium disilicate glass-ceramics.
      • Zitzmann N.U.
      • Özcan M.
      • Scherrer S.S.
      • et al.
      Resin-bonded restorations: a strategy for managing anterior tooth loss in adolescence.
      A 1- wing ovate pontic requires a bonding area for the wing (preferably to the central incisor or to the cuspid) of 30 mm2, with a thickness of least 0.7 mm, and a connector dimension of 3 × 2 mm (height x width) for Zirconia or 4 × 4 mm for lithium-disilicate.
      • Kern M.
      • Passia N.
      • Sasse M.
      • et al.
      Ten-year outcome of zirconia ceramic cantilever resin-bonded fixed dental prostheses and the influence of the reasons for missing incisors.
      All excursive movements must be carefully checked in order to avoid precontacts or interferences which would compromise good function and long-term stabilty.
      Soft tissue enhancement is often necessary to augment a deficient alveolar ridge, especially when the cuspid has erupted relatively distant from the central incisor. These mucogingival procedures will create the premises for a satisfactory emergence profile of the ovate pontic (Fig. 9).
      Figure 9
      Figure 9Gingival flap to obtain a natural looking emergence profile of the ovate pontic. The zirconia single wing bonded to the upper left cuspid without prior tooth preparation.
      The tight gingival contact of the ovate pontic might decrease over time because of the continuous eruption of the adjacent teeth. However, this problem is much less relevant than a potential infraocclusion of an implant-borne crown.
      • Thilander B.
      • Odman J.
      • Lekholm U.
      Orthodontic aspects of the use of oral implants in adolescents: a 10-year follow-up study.

      Infraocclusion: a change in perspective

      The current literature emphasizes that infraocclusion of an implant-borne crown is a frequent problem, which is not limited to the second and third decade of life, but which can also occur at an older age.
      Infraocclusion has great interindividual variability, is unpredictable in terms of its amount,
      • Schwartz-Arad D.
      • Bichacho N.
      Effect of Age on Single Implant Submersion Rate in the Central Maxillary Incisor Region: A Long-Term Retrospective Study.
      and cannot always be successfully managed by simply elongating the incisal margin or placing a new crown. Therefore, it could become a severe esthetic and functional problem.
      • Jemt T.
      • Ahlberg G.
      • Henriksson K.
      • et al.
      Tooth movements adjacent to single-implant restorations after more than 15 years of follow-up.
      Furthermore, the potential development of a darker shade of the labial gingiva due to resorption of the underlying alveolar bone, gingival recessions, and compromised health and morphology of the papillae,
      • Dierens M.
      • De Bruecker E.
      • Vandeweghe S.
      • et al.
      Alterations in soft tissue levels and esthetics over a 16 to 22-year period following single implant treatment in periodontally-healthy patients: a retrospective case series.
      makes this ortho-prosthodontic treatment alternative very risky and unpredictable in young patients with a high smile line and vertical maxillary excess.
      A spontaneous mesial drift of the natural teeth can induce a loss of the interproximal contact and a space opening mesial to the implant crown; this can cause esthetic complaints and food impaction.
      • Op Heij D.G.
      • Opdebeeck H.
      • van Steenberghe D.
      • et al.
      Facial development, continuous tooth eruption, and mesial drift as compromising factors for implant placement.
      The former existing agreement to place the implant only if 2 serial lateral headfilms, taken 6 months to 1 year apart, do not show any vertical growth (on average at 16-17 years of age in females and 20-21 years in males
      • Fudalej P.
      • Kokich V.G.
      • Leroux B.
      Determining the cessation of vertical growth of the craniofacial structures to facilitate placement of single-tooth implants.
      ) should be applied with caution due to the continuous process of bone remodeling and tooth eruption.
      • Dietschi D.
      • Shahidi C.
      • Krejci I.
      Clinical performance of direct anterior composite restorations: a systematic literature review and critical appraisal.
      Therefore, delaying implant placement in the esthetic zone of a young patient (especially with a high smile line) as long as possible seems to be a good advice.
      After completion of orthodontic space opening for the missing lateral incisor, it is necessary to provide the adolescent patient with an esthetically acceptable transitional prosthetic solution, preferable for a longer time than previously described in the literature.
      • Azevedo A.R.
      • Janson G.
      • Henriques J.F.
      • et al.
      Evaluation of asymmetries between subjects with Class II subdivision and apparent facial asymmetry and those with normal occlusion.
      A 1-wing resin bonded ovate pontic can provide satisfactory long-term stability in combination with good functional and esthetic performance during adolescence and young adulthood (Fig. 10). In patients with high smile line and vertical maxillary excess, a 1-wing FDP might even be a better alternative to an implant-borne crown in the esthetic zone when orthodontic space opening was preferable (Fig. 11).
      Figure 10
      Figure 10Composite restorations to harmonize the form and size of the central incisors and upper right lateral. Upper left lateral: 1-wing ovate pontic. Resin bonded wing in zirconia, ovate pontic in feldspathic ceramic. (Restorative Dentist: N. Perakis).
      Figure 11
      Figure 11Young patient with a high smile line. A 1-wing ovate pontic can be a solution for the long transitional period from adolescence to adulthood, possibly even avoiding the need for a single tooth implant at all.

      Conclusions

      In patients affected by unilateral agenesis of the upper lateral incisor, extraction of a contralateral small or peg-shaped lateral incisor and subsequent bilateral space closure is often indicated.
      Achieving an ideal esthetic outcome frequently requires adhesive reconstruction of the 6 upper anterior teeth. To date, minimally invasive direct or indirect techniques can be implemented, providing the young patients with the option of possible future reintervention, if necessary. Composite restorations,
      • Dietschi D.
      • Shahidi C.
      • Krejci I.
      Clinical performance of direct anterior composite restorations: a systematic literature review and critical appraisal.
      ultra-thin CAD-CAM veneers,
      • Patroni S.
      • Cocconi R.
      From orthodontic treatment plan to no prep CAD/CAM temporary veneers.
      and ceramic laminate veneers
      • Morimoto S.
      • Albanesi R.B.
      • Sesma N.
      • et al.
      Main Clinical Outcomes of Feldspathic Porcelain and Glass-Ceramic Laminate Veneers: A Systematic Review and Meta-Analysis of Survival and Complication Rates.
      offer excellent long term results, if appropriate procedures and materials are utilized.
      Unilateral space closure can be considered, when the extraction of the small upper lateral is not mandatory for positional or morphological reasons. In patients who present a concomitant subdivision malocclusion on the same side as the maxillary agenesis, it is preferable to close the upper space.
      In patients who need space opening for an implant-borne crown, positional requirements for the adjacent teeth, which might be smaller in size than average, have to be taken into account and addressed by restorative means.
      A 1-wing ovate pontic can be a good solution for the long transitional period from adolescence to adulthood, and in some patients even avoid the need for a single tooth implant at all - especially in young patients with a high smile line.
      The exciting synergy between orthodontics and contemporary adhesion dentistry requires implementation of an appropriate hierarchy of decisions in order to select the most advantageous approach for the individual young patient.
      • Perakis N.
      • Cocconi R.
      The decision-making process in interdisciplinary treatment: digital versus conventional approach.
      By utilizing appropriate materials and techniques, a 95% success rate of resin-bonded bridges and veneers after 10 years has been reported,
      • Patroni S.
      • Cocconi R.
      From orthodontic treatment plan to no prep CAD/CAM temporary veneers.
      ,
      • Perakis N.
      • Cocconi R.
      The decision-making process in interdisciplinary treatment: digital versus conventional approach.
      with a less than 5% need for reintenvention after this period, which proves that these approaches have already become reliable and rewarding treatment alternatives for young patients with a unilateral congenitally missing maxillary lateral incisor.

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