J Oral Maxillofac Surg58:1069-1073, 2000

Bony Augmentation of the MaxillarySinus Via a Le Fort I Osteotomy:

A Report of 3 CasesDavid M. Smith, DDS, MD,* Jeffery W. Armstrong, DDS,†

and William L. Davenport, DDS‡

The patient with partial edentulism and accompany-ing interarch alveolar positional discrepancies poses aparticular dilemma with respect to prosthetic recon-struction. Placement of endosseous implants is a via-ble option, but the interarch alveolar discrepancymust be addressed, along with the confounding situ-ation of limited bone height below the floor of themaxillary sinus secondary to ridge atrophy and sinusmorphology.

Various procedures have been described in theliterature for grafting the maxillary sinuses, both withsimultaneous and secondary implant placement.1,2

The literature has described techniques of augmenta-tion of the sinus floor through either a sinus mem-brane lift procedure3-6 or a “sandwich” technique ofsinus inlay grafting through a Le Fort I osteotomy withinferior and anterior repositioning to restore the ver-

tical and anterior dimension of the severely atrophicedentulous maxilla.7-10 In this report, a technique forgrafting the maxillary sinus through a Le Fort I osteot-omy in patients planned for implant-borne prostheticreconstruction who also have been identified as need-ing alteration of the maxillary alveolar position isdescribed and 3 patients who have undergone treat-ment with this technique are presented.

Surgical Technique

Presurgical treatment planning included clinicalanalysis of the remaining dentition, existing inter-arch relationship, and facial aesthetics. Panoramic,lateral, and posteroanterior radiographs were per-formed to determine the degree of maxillary sinuspneumatization and cephalometric skeletal posi-tion. The change in the vertical position of theedentulous alveolar ridges was then determined bythe desired interarch distance needed for pros-thetic restoration. Model surgery was completed onfacebow-mounted diagnostic casts, and acrylicsplints were fabricated to assist in intraoperativepositioning of the maxilla.

Each case was performed under general nasoen-dotracheal anesthesia. Cancellous and cortical bonewas harvested by use of a medial approach to theanterior iliac crest, taking care to obtain a corticalblock of bone from which the cortical “caps” de-scribed later would be fashioned. The Le Fort Iosteotomy was then performed in the usual fashion.Segmentalization, if required, was performed, andrepositioning of the maxilla was accomplished by

Received from Wilford Hall Medical Center, Lackland AFB, TX.

* Chief Resident, Department of Oral and Maxillofacial Surgery.

† Director of Residency Training, Department of Oral and Max-

illofacial Surgery.

‡ Chairman, Department of Oral and Maxillofacial Surgery.

The views expressed in this article are those of the authors and

do not reflect the official policy of the Department of Defense or

other Departments of the US Government.

Address correspondence and reprint requests to Dr Smith: 60

DS/SGDDS, 101 Bodin Circle, Travis AFB, CA 94535-1800; e-mail:

david.smith@60mdg.Travis.AF.mil

This is a US government work. There are no restrictions on its use.

0278-2391/00/5809-0023$0.00/0

doi:10.1053/joms.2000.8756

using the prefabricated acrylic splint and maxillo-mandibular fixation. Before final fixation of themaxilla, the sinus mucosa was removed and mor-selized corticocancellous bone was condensed intothe sinuses (Fig 1). Using suture package foil toform a template, the outline of each sinus wasreproduced, and the bone caps to be placed over

the condensed particulate bone were fashionedfrom the cortical blocks of bone. The cortical capswere then placed flush over the maxillary sinusesand secured with angled positional screws (Fig 1).The maxilla was then placed into the final positionand fixed with microplates. The grafts were al-lowed to consolidate for a period of 4 to 6 months,

FIGURE 1. Technique of sinus augmentation: A, The mucosa isremoved from the floor of the sinuses. B, Morselized, autogenouscorticocancellous bone is condensed into the sinuses. C, “Caps”fashioned from pieces of autogenous cortical iliac bone are positionedover the condensed particulate bone. Custom templates made from thefoil from suture packages are used to shape the caps. D, The corticalcaps are held in place with angulated position screws placed in abicortical fashion. E, The maxilla is placed into the desired finalposition and fixed with microplates.

1070 SINUS GRAFTING VIA LE FORT I OSTEOTOMY

after which implant placement and eventual pros-thetic reconstruction were completed.

Report of Cases

Case 1A 37-year-old woman presented to the prosthodontic

department and requested prosthetic reconstruction for herbilaterally missing maxillary posterior teeth. These teethhad been missing for many years and had had no prostheticreplacement. The result was flaring of the maxillary anteriordentition and a severe loss of vertical dimension. Her re-maining mandibular molars were occluding with her max-illary alveolar ridge, and the posterior interarch distancewas inadequate for any type of opposing prosthesis. Anytreatment plan for prosthetic reconstruction for this patientwould have to include increasing the interarch distance;alveoloplasty alone would not provide enough increase ininterarch distance because of the prominent maxillary si-nuses and combined with the lack of residual alveolarheight. The preoperative panoramic radiograph showedprominent pneumatization of the maxillary sinuses and in-adequate alveolar height for implant placement (Fig 2).

The patient’s treatment plan was developed in concertwith the referring prosthodontic department. A Le Fort Iosteotomy with a differential impaction would be per-formed so that the posterior maxilla could be superiorlyrepositioned, increasing the interarch distance. Augmenta-tion of the sinuses would then be accomplished with au-

FIGURE 4. Panoramic radiograph showing final implant placement.

FIGURE 5. A, Reformatted CT scan of proposed implant site withradiopaque marker before bony augmentation showing lack of ade-quate alveolar bone for implant placement. B, Same implant site afterbony augmentation by described method.

FIGURE 2. Panoramic radiograph taken preoperatively showing lackof interarch distance and inadequate alveolar bone height for implantplacement secondary to alveolar resorption and prominent maxillarysinus pneumatization bilaterally.

FIGURE 3. Custom-shaped cortical “caps” placed over condensedparticulate bone grafts and fixed with single angulated position screwsbilaterally.

SMITH, ARMSTRONG, AND DAVENPORT 1071

togenous bone harvested from the anterior iliac crest andcondensed into the sinuses bilaterally at the time of down-fracture. The remaining mandibular molars were to be re-moved (secondary to supraeruption and severe mesial tip-ping) and alveoloplasty of the mandibular ridge performed.Implants then would be placed as a secondary procedure inboth the maxillary and mandibular posterior regions aftersufficient healing was complete.

The patient was taken to the operating room and placedunder general anesthesia administered by nasoendotrachealintubation. Custom cast arch bars fabricated by the refer-ring prosthodontist were secured to the teeth, and the LeFort I procedure was begun. Harvest of bone from theanterior iliac crest bone was initiated simultaneously by asecond surgical team. Final position of the maxillary seg-ment was ensured by use of an acrylic splint. The patientwas then placed into maxillomandibular fixation, bony in-terferences were relieved, and, after the desired position ofthe maxilla was obtained, attention was directed to theplacement of the bone grafts into the sinuses. To accom-plish this, the sinus floors were meticulously stripped of allsinus mucosa. Morselized corticocancellous bone then wascondensed into each of the sinuses. The caps of corticalbone were fashioned as previously described and placedover the condensed particulate bone and secured with asingle 1.5-mm position screw (Fig 3). Care was taken toensure that there were no interferences from the graftedbone that would prevent achievement of the previouslydetermined final maxillary position. Fixation of the maxillawas accomplished by use of microplates, and the surgical

sites were closed in the usual fashion. The patient was thentaken out of maxillomandibular fixation, and the final oc-clusion was verified.

The grafts were allowed to consolidate for a period of 6months before implant placement. During this period, thepatient wore transitional removable prostheses to preservethe interarch distance gained by the Le Fort I procedure andto prevent any relapse of alveolar position. Implants thenwere placed (Fig 4), with all implants achieving osseointe-gration.

Case 2A 50-year-old woman was referred from the prosthodon-

tic department for evaluation of an interarch discrepancy.As a consequence of alveolar resorption, the patient was leftwith edentulous posterior regions that had resulted in ex-cessive interarch distance so that any prosthesis fabricatedwould have an unsightly and unnatural appearance becauseof increased crown length. The crown-to-implant ratiowould be excessive as well, compromising stability of thefinal prosthesis. Additionally, the patient had some degreeof vertical maxillary excess.

The treatment plan included a 3-piece segmental Le FortI osteotomy to inferiorly reposition the posterior edentu-lous segments and obtain a more ideal interarch distance,and a slight superior repositioning of the anterior segmentto obtain a more aesthetic incisor display. The restorativetreatment plan called for implant-borne fixed prostheses.However, as a result of the alveolar resorption and proxim-ity of the maxillary sinuses, inadequate alveolar crest heightremained for implant placement; therefore, the treatmentplan also included bony augmentation of the maxillary si-nuses. This was accomplished at the time of Le Fort Idownfracture after simultaneous harvest of autogenousbone from the anterior iliac crest. After downfracture, thevertical osteotomies were completed, and the maxilla wassegmentalized. A prefabricated acrylic splint was used toposition the segments, which were fixed in place with lagscrews placed through the splint and into the alveolarsegments. After final vertical positioning was obtained, mor-selized corticocancellous bone was condensed into themaxillary sinuses bilaterally after removal of all the sinusmucosa, and cortical caps were fashioned to overlay thegrafts. These were held in place using 2 positional screwsbilaterally. The maxilla was then placed into the desiredposition and fixed with microplates. The patient remainedin the acrylic splint for a period of 6 weeks to allow foradequate consolidation.

FIGURE 6. A, B, Intraoral views showing sites after restoration with implant-borne fixed prostheses displaying more aesthetic crown forms and amore ideal crown-to-implant ratio than could have been achieved with the preexisting interarch distance.

FIGURE 7. Diagnostic casts showing decreased interarch distanceand resulting Class III skeletal relationship secondary to alveolar ridgeresorption.

1072 SINUS GRAFTING VIA LE FORT I OSTEOTOMY

Reformatted computed tomography (CT) scans with ra-diopaque markers over the proposed implant sites wereobtained preoperatively to determine the degree of alveolarbone insufficiency, as well as after the augmentation, justbefore implant placement. Side-by-side comparisons of thescans of each implant site before and after augmentationwere made to determine that the patient now had adequatebone available for implant placement (Fig 5). The patientthen proceeded to have prosthetic reconstruction with amore ideal interarch distance that allowed for more aes-thetic prostheses as well as a more stable crown-to-implantratio (Fig 6).

Case 3A 44-year-old man sought treatment with multiple miss-

ing maxillary teeth, including posterior teeth bilaterally, aswell as some anterior teeth. The patient not only possessedinadequate bone posteriorly, but the degree of alveolaratrophy anteriorly had rendered the ridge too knife-shapedto allow for implant placement. Additionally, the maxillawas retrusive and in a poor interarch relationship for properreconstruction (Fig 7). The treatment plan called for a3-piece segmental Le Fort I osteotomy to advance the entiremaxilla to improve the interarch relationship anteroposte-riorly, as well as an impaction of the posterior segments toimprove the occlusal relationship of the remaining poste-rior teeth. Interarch distance also was to be increased,providing adequate vertical dimension for aesthetic pros-thetic restoration.

The patient underwent a segmental 3-piece Le Fort Iosteotomy in which the segments were mobilized and fixedin their new position by use of a prefabricated acrylic splint.The maxillary sinuses were then grafted with autogenousiliac crest bone by using the previously described tech-nique. After placement and fixation of the cortical caps overthe morselized corticocancellous bone that had been con-densed into the sinuses bilaterally, the maxilla was reposi-tioned and fixed with microplates. The patient then hadprosthetic reconstruction with implant-borne prostheses.

Discussion

In each of these cases, the patients had an identifiedneed for maxillary positional change either en toto orin segments and, therefore, Le Fort I osteotomieswere planned. Because the ultimate treatment planincluded implant-borne prostheses, access to themaxillary sinuses that is so readily available at the timeof Le Fort I downfracture was used for the placement

of autogenous bone grafts. This method of graftingallows placement of both cortical and cancellousbone under direct visualization, thus maximizing con-trol of the grafted material and offering a very predict-able outcome with regard to the bony augmentation.In each of these cases, radiographic evidence of bonyconsolidation was evident, and osseointegration of allimplants was obtained in the 2 cases that have com-pleted prosthetic reconstruction.

This method of maxillary sinus bone grafting offersanother means of bony augmentation of the maxillarysinus. In those cases in which a Le Fort I osteotomy isindicated as part of the preprosthetic treatment ofmaxillary alveolar position discrepancies, it is a simpleand effective method to contain grafts of compactedcancellous bone while achieving the needed posi-tional changes of the teeth or alveolar ridges.

References1. Block MS, Kent JN: Maxillary sinus bone grafting, in Block MS,

Kent JN: Endosseous Implants for Maxillofacial Reconstruction,Philadelphia, PA, Saunders, 1995, p 478

2. Misch CE: Maxillary sinus augmentation for endosteal implants:Organized alternative treatment plans. Int J Oral Implant 4:49,1987

3. Boyne PJ, James RA: Grafting of the maxillary sinus floor withautogenous marrow and bone. J Oral Surg 38:613, 1980

4. Raghoebar GM, Brouwer TJ, Reintsema H, et al: Augmentationof the maxillary sinus floor with autogenous bone for theplacement of endosseous implants. J Oral Maxillofac Surg 51:1198, 1993

5. Smiler DG, Johnson PW, Lozado JL, et al: Sinus lift grafts andendosseous implants. Dent Clin North Am 36:151, 1992

6. Wood RM, Moore DL: Grafting of the maxillary sinus withintraorally harvested autogenous bone prior to implant place-ment. Int J Oral Maxillofac Implants 3:209, 1988

7. Bell WH, Buche WA, Kennedy JW, et al: Surgical correction ofthe atrophic alveolar ridge. Oral Surg 43:485, 1977

8. Farmand M: Horse-shoe sandwich osteotomy of the edentulousmaxilla as a preprosthetic procedure. J Maxillofac Surg 14:238,1986

9. Keller EE, Van Roekel NB, Desjardins RP, et al: Prosthetic-surgical reconstruction of the severely resorbed maxilla withiliac bone grafting and tissue-integrated prostheses. Int J OralMaxillofac Implants 2:155, 1987

10. Sailer HF: A new method of inserting endosseous implants intotally atrophic maxillae. Craniomaxillofac Surg 17:299, 1989

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