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E

xcessive gingival display is anunattractive smile character-

istic with multiple etiologies.Vertical maxillary excess, supra-eruption of the maxillary incisors,and shortness or hypermobilityof the upper lip are some of themost common factors involved.1,2

Vertical maxillary excess is char-acterized by excessive posteriorand anterior dentoalveolar heightand is often associated with exces-sive lower facial height and a wideinterlabial gap. From a sagittal

view, such a patient may also havea convex profile due to apparentdownward and backward mandib-ular rotation.3

A patient with vertical max-illary excess exhibiting these facialcharacteristics can benefit greatlyfrom a maxillary impaction LeFort I osteotomy.3,4 This proce-dure not only reduces the gingival

display when smiling and the in-cisor display at rest, but also pro-

motes an upward and forwardrotation of the mandible thatreduces the lower facial heightand the interlabial gap, oftenresulting in a more orthognathicprofile. Because orthognathicsurgery is associated with con-siderable costs and risks, howev-er, alternative treatment optionsare often explored, includingorthodontic intrusion of the max-illary incisors.

The maxillary incisors canbe predictably intruded about2mm with orthodontic appli-ances.5 Any further correction isdifficult to achieve or may gener-ate esthetic problems, such as areverse smile architecture due tothe discrepancy between the pos-terior occlusal planes and the ante-rior incisal plane (Fig. 1). To

VOLUME XLII NUMBER 3 2008 JCO, Inc. 157

CASE REPORT

Reduction of Gingival Display with MaxillaryIntrusion Using Endosseous Dental Implants

FLAVIO URIBE, DDS, MDSBRUCE HAVENS, DDS, PHDRAVINDRA NANDA, DDS, PHD

Dr. Uribe is Assistant Professor and Program Director and Dr.Havens is Assistant Professor, Division of Orthodontics, and Dr.Nanda is Professor and Head, Department of Craniofacial Sci -ences, Alumni Endowed Chair, School of Dental Medicine,University of Connecticut, Farmington, CT 06032. Dr. Nanda isalso an Associate Editor of the Journal of Clinical Orthodontics;e-mail: [email protected].

Dr. HavensDr. Uribe Dr. Nanda

Fig. 1 A. Reverse smile archi-tecture from maxillary incisorintrusion that produced verticaldiscrepancy between posteriorocclusal planes and anteriorincisal plane. B. Problem is mostapparent from front view.

A

B

2008 JCO, Inc. May not be distributed without permission. www.jco-online.com

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increase the degree of maxillaryincisor intrusion, the posteriorocclusal plane must be alteredthrough a leveled or canted intru-sion. Unfortunately, superior dis-placement of the maxillary occlusalplane is not possible in an adultpatient without surgery, unlessadjuncts such as skeletal anchor-age are used.6-10

This article describes a pa-

tient with excessive gingival dis-play in whom the incisors wereintruded 5mm at the incisal level,with a significant esthetic effectcomparable to that of a Le Fort Imaxillary impaction. Anchoragefrom endosseous dental implantsin the posterior maxillary seg-ments was used to achieve thissignificant incisor intrusion andalter the cant of the occlusal plane.

Diagnosis

A 38-year-old female re-quested the restoration of missingteeth (Fig. 2). Dental caries hadresulted in the loss of all the max-illary right molars and left pre-molars, as well as the mandibularleft first molar and right secondpremolar. The mandibular rightthird molar was impacted. The

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Reduction of Gingival Display wi th M axilla ry Intrusion Using Dental I mplants

Fig. 2 38-year-old female patient with mutilated dentition and excessive upper gingival display before treatment.

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patient had many amalgam res-torations and a temporary cementrestoration on the occlusal sur-face of the maxillary left secondmolar. The maxillary and man-dibular incisors and canines hadmoderate wear on the incisaledges. The width, but not theheight, of the maxillary alveolarridges was reduced, especially onthe right side. Both the height andwidth of the mandibular alveolar

ridges in the edentulous sites werereduced. No interocclusal spacewas available for a prosthesis inthe maxillary left premolar area,and the mandibular right secondmolar was supraerupted, contact-ing the maxillary alveolar ridge.

The patients facial skeletaland soft-tissue profiles were con-vex due to mild maxillary prog-nathism. She had an increasedlower facial height with a vertical

maxillary excess that was evidentin smiling, with a display of

approximately 8mm of gingiva onsmiling and 4mm of the maxillaryincisors at rest. The maxillary andmandibular incisors were supra-erupted and upright (Table 1).

The canine relationship wasClass I on the right side and edge-to-edge on the left; the molar rela-tionship was indeterminate dueto the numerous missing molars.The patient also had an impinginganterior deep bite.

Treatment Plan

The general treatment objec-tives were to reduce the anteriordeep bite and excessive gingivaldisplay through intrusion of themaxillary incisors, achieve a ClassI canine relationship, and createadequate space for a fixed pros-thesis. The specific objectiveswere to reduce the skeletal and

soft-tissue convexity throughintrusion of the maxillary molars

and resultant mandibular autoro-tation, which would also reducethe lower facial height and theinterlabial gap. The maxillaryincisors were to be intruded 5mmand the lower incisors maintainedvertically, correcting the overbiteand maximizing the reduction of

the gingival display. The molarintrusion would also tend to deep-

VOLUME XLII NUMBER 3 159

Uribe, Havens, and Nanda

Fig. 3 Setup casts depicting treatment objectives.

TABLE 1CEPHALOMETRIC DATA

Pre- Post-treatment Treatment

SNA 86 85SNB 77 78ANB 9 7SN-MP 42 39U1-SN 80 97IMPA 90 93

U1-NF 33 28L1-MP 43 42

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en the anterior overbite, prevent-ing the development of an anteri-or open bite despite the significantincisor intrusion.

The plan was to maintainthe maxillary incisors in theanteroposterior dimension at theincisal level, but to move the rootslingually. The mandibular incisorswould be tipped 4mm labially,and the maxillary left molars pro-tracted 3mm. Endosseous im-

plants were to be placed in theedentulous site of the maxillaryleft first premolar anddistal to themaxillary right second premolar.The mandibular left second molarwould be tipped back 3mm, and abridge would be placed to restorethe first molar edentulous site.

Finally, the mandibular right firstmolar would be maintained, and abridge would be made at the endof treatment to restore the missingsecond premolar (Fig. 3).

Treatment Progress

The patient was first referredfor permanent restoration of theocclusal surface of the maxillaryleft second molar, as well as ex-

traction of the supraerupted man-dibular right second molar. AVisualized Treatment Objectiveand an occlusogram were used todetermine the proper location ofthe implants and transfer them tothe initial cast (Fig. 4). After theappropriate sites were identified,

the bone was evaluated to ensureadequate height and width of thealveolar bone. Two 3i* maxillaryendosseous dental implants wereplaced, one in the right first molararea and the other in the edentu-lous left first premolar site.

During the osseointegrationperiod, .022" maxillary and man-dibular appliances were placedfor initial leveling and alignment.Two months after the implants

were inserted, abutments wereplaced. A temporary acrylic toothwas cemented to the top of themaxillary right first molar dentalimplant, and a preformed bandwas cemented around the tempo-rary tooth. A custom-made bandwith a soldered bracket wascemented directly to the abutmentof the maxillary left premolar.

An .017" .025" nickel tita-nium Connecticut IntrusionArch** was attached from max-illary first molar to first molar todeliver a continuous intrusiveforce to the incisors, which wereligated as a unit with an .017" .025" stainless steel wire segment.

Fig. 4 Endosseous dental implant placement plan, based on transfer of information from occlusogram to castfor stent fabrication and then to clinical setting. Implants were placed before orthodontic appliances.

Fig. 5 Tipback force on molarcounteracted by endosseous den-tal implant, preventing dissipationof intrusive force.

Fig. 6 Maxillary incisor intrusionwith .017" x .025" nickel titaniumConnecticut Intrusion Arch andmandibular second molar up-righting spring.

*BIOMET 3i, 4555 Riverside Drive, PalmBeach Gardens, FL 33410; www.biomet3i.com.

**Ortho Organizers, 1822 Aston Ave.,Carlsbad, CA 92008; www.orthoorganizers.com. CNA is a trademark.


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The tipback and extrusive force onthe molars were counteracted bythe implants, directly on the rightside and indirectly on the left side

(Fig. 5), so that the intrusive forcewas the only component of theforce system producing toothmovement. A segment was addedto connect the maxillary left im-plant to the first molar, from whichthe intrusion arch was extended.Because the bracket on theimplant was more gingival, thisassembly helped intrude the max-illary first molar and reduce thelower facial height. In the lowerarch, a heavy continuous .017" .025" stainless steel wire wasplaced from the mandibular rightfirst molar to the left second molar.An uprighting spring made from.017" .025" CNA Beta III wire**was placed on the second molar totip the molar back (Fig. 6).

The significant maxillaryincisor intrusion created a reversesmile architecture (Fig. 7), neces-

sitating intrusion of the caninesand premolars on the right side.The canines were intruded about3mm with a cantilever on the rightside and a V-bend on the left sidefrom the maxillary left premolarimplant (Fig. 8). The right firstand second premolars were intrud-ed with short cantilevers extend-ed from the first molar implant.

Once the anterior and posteriorintrusion was completed, contin-uous archwires were inserted inboth arches. A mushroom loopwas placed to close a space thathad opened distal to the maxillaryleft lateral incisor.

After 42 months of treat-ment, appliances were removed,and the patient was referred tothe restorative dentist for place-ment of bridges in the mandibularposterior regions and crowns onthe maxillary endosseous im-plants. Crown-lengthening gin-givectomies were recommendedfor the anterior teeth to reducethe residual gingival display, alongwith composite veneers or crownsto restore the worn incisal edges.The patient was satisfied enoughwith the anterior esthetics that shedecided to limit her prosthodontic

treatment to the posterior occlusalrehabilitation (Fig. 9).

Discussion

Anchorage from conven-tional endosseous dental implantscan be used not only to restoreedentulous areas, but also toachieve significant anterior intru-

sion, with esthetic results com-parable to those of surgicalmaxillary impaction. Althoughsignificant root resorption mightbe expected with this amount ofintrusion, the final radiographsrevealed only mild resorption,consistent with conventionalorthodontic mechanics (Fig. 9).

A significant mechanicaladvantage is obtained with leverarms that generate intrusive forcesanterior to the buccal segments.This method provides a versatileway to deliver the desired forcevectors from remote areas of themouth. Significant tooth move-ment can be achieved whenintruding the incisors from endos-seous molar implants, because theforce activation is not dissipatedby the tipback side effect of theanchorage unit.

Fig. 8 A. Intrusion arch maintaining initial incisor intrusion, with can-tilever used to intrude right second premolar from endosseous implant.Canine and first premolar were intruded using same force system. B. V-bend from endosseous implant in maxillary left first premolar site used

to intrude canine and molar.

Fig. 7 Vertical discrepancy be-tween maxillary buccal segmentsand incisor plane after maxillaryincisor intrusion, requiring cant-ed intrusion of buccal segments.



A B

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Fig. 9 A. Patient after 42 months oftreatment, showing significant re-

duction of excessive gingival dis-play and superior autorotation ofmandible. Prosthetic restorationswere fabricated for endosseousdental implants and edentulousareas. B. Superimposition of ceph-alometric tracings before and aftertreatment.


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1. Sarver, D.M.: Facial analysis and thefacial esthetic problem list, in EstheticOrthodontics and Orthognathic Surgery,

Mosby, St. Louis, 1998, pp. 2-55.2. Sarver, D.M.; Proffit, W.R.; and

Ackerman, J.L.: Evaluation of facial softtissues, in Contemporary Treatment ofDentofacial Deformity, ed. W.R. Proffit,R.P. White Jr., and D.M. Sarver, Mosby,St. Louis, 2003, pp. 92-126.

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4. Legan, H. and Conley, S.C.: Biomech-

anical factors in surgical orthodontics, in

Biomechanics and Esthetic Strategies in

Clinical Orthodontics, ed. R. Nanda,

Elsevier Saunders, St. Louis, 2005, pp.310-329.

5. Ng, J.; Major, P.W.; Heo, G.; and Flores-Mir, C.: True incisor intrusion attainedduring orthodontic treatment: A system-atic review and meta-analysis, Am. J.Orthod. 128:212-219, 2005.

6. Creekmore, T.D. and Eklund, M.K.: Thepossibility of skeletal anchorage, J. Clin.Orthod. 17:266-269, 1983.

7. Sugawara, J.: A bioefficient skeletalanchorage system, inBiomechanics andEsthetic Strategies in Clinical Ortho-

dontics, ed. R. Nanda, Elsevier Saun-

ders, St. Louis, 2005, pp. 295-309.8. Everdi, N.; Keles, A.; and Nanda, R.:

Orthodontic anchorage and skeletal im-

plants, in Biomechanics and EstheticStrategies in Clinical Orthodontics, ed.R. Nanda, Elsevier Saunders, St. Louis,2005, pp. 278-294.

9. DeVincenzo, J.P.: A new non-surgicalapproach for treatment of extremedolichocephalic malocclusions, Part 1:Appliance design and mechanotherapy,J. Clin. Orthod. 40:161-170, 2006.

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REFERENCES



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