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Abstract: A case is reported of a 66-year-old womanwho could not use a conventional, full upper denturebecause of a gag reflex. In the maxillary alveolar ridge,restoration was performed on a moderately atrophied,edentulous anterior area and a small defect in theright-side posterior area. In the mandibular alveolarridge, restoration was performed on a moderate osseousdefect in each molar area resulting from tooth extractiondue to severe periodontal disease. Based on carefultreatment planning, four types of bone graft were usedwith previously designed osseointegrated implants.The atrophied maxillary alveolar ridge was restoredwith veneer iliac bone grafts to avoid fenestrationduring implant placement, while alveolar processdeficiency was restored using inlay and sinus bonegrafts as placements for long implant fixtures. Thedefects in the mandibular alveolar bone were filledwith corticocancellous bone chips at the implantplacement sites. A combination of immediate andsecondary placement of Brånemark fixtures was used.Bone-anchored bridge-type implant prostheses werefitted approximately twelve months after surgery.Three years later, there had been no failure of implantfixtures and satisfactory functional and cosmetic

restoration had been maintained. (J. Oral Sci. 45, 227-232, 2003)

Key words: gag reflex; osseointegrated implant;treatment planning; four types of bonegraft.

IntroductionThis paper reports a case in which careful treatment

planning was used in providing implants for a patient withpoor bone volume and quality at the desired implant sites.Based on presurgical examination and diagnosis, severaltypes of bone graft were planned to overcome these bonedeficiencies. In the edentulous maxilla, an inlay graft, asinus graft and three veneer grafts were used. In thealveolar ridge at the molar area on both sides of themandible, moderate osseous defects were filled withcorticocancellous bone chips. Some implant fixtures wereinstalled simultaneously with these bone grafts. Otherfixtures were installed in a secondary procedure, limitedto the anterior region of the maxilla where the veneergrafts had been placed. Bone-anchored bridges were putin place, which three years after surgery were still functionaland providing a satisfactory cosmetic result.

Case ReportThe patient was a 66-year old Japanese woman in good

general health and a non-smoker, who for fifteen years

Journal of Oral Science, Vol. 45, No. 4, 227-232, 2003

Correspondence to Dr. Minoru Hori, 962-120 Komejima, Showa-machi, Kitakatushika-gun, Saitama 344-0155, JapanTel: +81-48-746-3115Fax: +81-48-746-2810E-mail: hori2010@sea.plala.or.jp

Treatment planning in a case of restoration of the maxilla andmandible using osseointegrated implants with four types of

bone graft

Minoru Hori§, Katsuhiko Kaneko‡, Daisuke Harada§, Kouji Nakanishi§,Takayoshi Tanaka§, Teruhiko Ishii§ and Hiroshi Tanaka§,†

§Department of Oral and Maxillofacial Surgery, Nihon University School of Dentistry, Tokyo 101-8310†Division of Immunology and Pathobiology, Dental Research Center,

Nihon University School of Dentistry, Tokyo 101-8310‡Kuno Dental Clinic, Soka-shi, Saitama 340-0034

(Received 5 March and accepted 24 October 2003)

Case report

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before her referral to the Nihon University Dental Hospitalhad used a partial denture in the maxilla. However, twoweeks prior to her visit, the first and second molars on bothsides of the mandible, as well as the remaining three teethin her maxilla, had been extracted because of severeperiodontal disease, and she had been given a full upperdenture controlled by a soft resin temporary treatmentliner. As well as the gag reflex with this new denture, shereported that it was not effective for mastication and shefound it uncomfortable to wear for extended periods. Shehad therefore been referred to the hospital for implanttreatment to the maxilla as an alternative to the denture.

As well as an edentulous maxilla, intraoral examinationrevealed missing teeth 2-3 and 14-15 in the mandible.The patient wore partial dentures in those areas, butreported no problems in using them. The alveolar ridgein the maxilla showed moderate horizontal and verticalatrophy in the anterior area. The second molar area of theridge in the mandible was moderately concave on theright side, while the left side was moderately concave atthe first molar area of the ridge.

A panoramic X-ray examination (Fig. 1) showed that,on the right side of the maxilla, there was a moderateconcavity in the area of the first and second molars andthat the distance from the ridge to the floor of the sinuson the left side had been reduced to approximately 7 mmat the thinnest point. It also revealed clearly definedradiolucent areas in the second molar area on the right sideand in the first molar area on the left side of the mandible.These radiolucent areas corresponded to part of the areafrom which three molar teeth (15, 18 and 30) had beenextracted due to severe periodontal disease, which was alsothe probable cause of osseous deficiencies revealed by thepanoramic X-ray examination.

Computerized tomography (CT) producing transaxialimages of the maxilla at 2-mm intervals revealed anosseous defect in the right-side first and second molararea, but no significant findings on the left side. It alsoshowed that in the maxilla from the right molar to the leftmolar region, the width of the alveolar ridge had beenreduced to the level of the root apices, and there wasinadequate bone of implantable quality. The CT sinus viewdid not reveal any problems in the right or left maxillarysinus membrane.

A lateral cephalometric X-ray examination, togetherwith clinical assessment, allowed the resorbed area of thepatient’s maxilla to be classified as a “C” type morphology,according to the Lekholm-Zarb classification system (1).

Treatment PlanningTreatment planning for this patient required careful

selection of the types of bone graft to be used, keeping inmind not only her current condition, but also the desiredend result of a satisfactory relationship between the jawsand the shape of the dental arches. To select the types ofbone graft, first, the relationship between the maxilla andmandible was determined using an articular diagnostic castmounted on a semiadjustable articulator. The diagnosticcast also revealed in both jaws many areas with deficienciesin bone volume and/or height, as well as small osseousdefects in the alveolar ridge. In addition, the cast showedthat there was a poor horizontal relationship on both sidesbetween the maxilla and mandible.

Based on the findings of the panoramic X-ray exami-nation, the CT scan and the diagnostic cast, it was decidedto use three buccal veneer bone grafts to augment thevolume of the alveolar ridge in the edentulous maxilla, fromthe right premolar to the left premolar region. For the firstand second molar area of the right side of the maxilla, itwas considered that the softness of the maxillary bone madeit unsuitable to use corticocancellous bone chips to fill thedefect. Therefore, an inlay bone graft was chosen, whichalso achieved a cosmetically acceptable level base for aprosthesis that was also partly based on the veneer bonegrafts. In addition, use of an inlay graft made it easier tosimultaneously insert a 10 mm implant fixture that wouldbe likely to retain stability.

On the left side of the maxilla from the premolar to themolar area, a sinus bone graft was selected to increase thealveolar height for the placement of longer implant fixtures.Corticocancellous bone chips were selected to fill theosseous bone defects in the mandible and increase alveolarheight, as it was considered unnecessary to use the limitedsupply of iliac bone graft material to treat defects that werenot severe.

Surgical ProcedureBone was harvested from the right iliac crest using a 7

cm incision, starting 1 cm posterior to the anterior superioriliac spine (to avoid damaging the lateral superficial branchof the femoral nerve), and running parallel to the iliac crest.A 4 cm long bony lid, encompassing the iliac crest andattached only to the inner periosteum, was tilted medially.A full-thickness iliac block of approximately 4 × 3 × 1 cmwas harvested, including the iliac crest.

An intraoral approach to the maxilla was made using ahorseshoe-shaped incision along the alveolar ridge fromthe region of the right second molar to the left second molar.The alveolar crest was revealed by raising a mucoperiostealflap, and the nasal floor was identified. The entire bonypalate and alveolar process were exposed, and the extentof the nasopalatine canal was explored.

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The material for the inlay bone graft and the threeveneer grafts was shaped and trimmed with a bur to createthe largest possible contact surfaces with the underlyingbone surface. The three contiguous veneer bone grafts wereplaced in alignment to cover the deficient labial area ofthe maxillary alveolar process, and holes were drilledwith a guide bur from the lateral aspect of the bone graftsand into the alveolar process. These were used for a totalof four titanium mini-screws to hold each graft in place.The screws were removed six months later, during thesecondary implant procedure.

Next, the inlay bone graft was held firmly against theconcavity on the right side of the maxillary alveolar ridge,and a hole was drilled with a guide bur through the graftand into the alveolar ridge. The hole was used to insert atitanium mini-screw to hold the graft in place. A self-tapping, 13 mm long implant fixture of 3.75 mm diameterwas then installed in the bone graft, according to theBrånemark procedure. The temporary mini-screw was thenremoved. In addition, another self-tapping, 10 mm longimplant fixture of 3.75 mm diameter was inserted at thefirst molar area of the maxilla, between the inlay graft andthe first of the three contiguous veneer grafts (Fig. 2).

The residual iliac bone material that had been harvestedfor grafts was processed to provide cancellous bone chipsfor the sinus augmentation procedure at the left side of themaxilla. This was performed simultaneously with theplacement of two standard Brånemark fixtures of 4 mmdiameter and a length of 13 mm, as well as one self-tapping fixture 3.75 mm in diameter and 10 mm long(Fig. 3). Bone chips were used to densely fill the cavityin the maxillary sinus area around the exposed tips of thestandard fixtures (Fig. 4).

In the mandible, two standard Brånemark fixtures each3.75 mm × 13 mm were placed at the right-side secondmolar area, and two fixtures 3.75 mm × 10 mm and 3.75mm × 15 mm were placed at the left-side first molar area(Fig. 5). Bone chips were then used to firmly fill thecavities around the exposed upper half of the fixturethreads (Fig. 6). Finally, the initial incision in the alveolarridge was closed using 4-0 sutures, together with horizontalmattress sutures to provide a watertight closure.

After approximately five months, a series of dental X-ray films and a panoramic X-ray film were obtained tocheck the condition of the bone grafts. The volume of bonehad slightly decreased in each graft and the density hadincreased, indicating that bone remodelling was almostcomplete and the secondary placement of implants couldbe performed. All the four mini-screws in the veneergraft in the maxilla were removed under local anesthesia,and three additional implant fixtures were placed in the

maxilla, two in the right-side premolar area (one standardtype 10 mm long × 4 mm diameter, and one Mark II, self-tapping type 13 mm long × 3.75 mm diameter) and onein the left-side canine area (Mark II, self-tapping type 13mm long × 3.75 mm diameter) (Fig. 7).

Six months later, second-stage abutment connectionsurgery was performed. Eight implant fixtures were placedto support a full-arch fixed prosthesis in the maxilla. Inthe mandible, four fixtures were placed (two on the rightand two on the left side) to support a bridge-type prosthesis.Clinical postoperative examinations were undertakenregularly in the interval prior to the abutment operation,as well as at 2, 4, 6, and 12 months after completedprosthodontic treatment; thereafter, the patient wasexamined annually. Radiographic examination wasperformed immediately after the abutment connection,and after a further 6 months, 1 year, 2 years, and 3 years(Fig. 8). These final-stage X-rays revealed slight resorptionof approximately 1 mm around two fixtures in the maxilla,but otherwise the results were successful. There were noclinical problems, and the patient reported that she coulduse the prostheses without difficulty.

DiscussionThe restoration of totally or partially edentulous jaws

with endosseous implants is usually successful, but it isoften difficult to treat a severely or moderately resorbedmaxilla. To overcome this, various types of bone graft areneeded to augment the alveolar ridge (2). However,treatment planning in these cases is not easy, due to theinfluence of various factors on the final outcome (3). Thesuccess rate of bone grafts is variable, and the implantsurvival rate is unpredictable (4,5). In addition, designingthe implant prosthesis to give the patient the expectedresult is complex, because the design must take intoconsideration the position, direction and number of implantfixtures, as well as such factors as the likely level of dentalhygiene.

In the mandible, similar success rates have been reportedfor all types of bone graft, placed simultaneously orsecondarily (5,6). In the maxilla, most authors agree thatinlay bone grafts, veneer bone grafts and the use ofcancellous bone chips are usually successful, and theyrecommend similar surgical procedures (7). However,although a consistent success rate of 85% to 98% hasbeen reported for sinus bone grafts (8), opinions varyabout the appropriate time to perform them and whetherblock or chip type grafts should be used (9). The biggestvariation in authors’ results occurs in relation to implantsurvival rates when combined with any type of bone graftin the maxilla: a range of 25% to 85% has been reported

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Fig. 6 Bone chips are firmly packed around the exposedfixture threads in the mandible. Arrow indicates howfixture thread is covered.

Fig. 1 Initial panoramic X-ray examination:(a) Moderateconcavity in 1st and 2nd molar area, (b) Sinus heightreduced to 7 mm, (c) & (d) Radiolucent areas at toothextraction sites.

Fig. 2 Inlay bone graft at the right side of the maxillaryalveolar ridge with simultaneous placement of self-tapping fixture (indicated by arrow) through a holedrilled in the graft.

Fig. 3 Sinus augmentation at left side of maxilla, withsimultaneous placement of implant fixtures. Arrowindicates exposed tip of a standard Brånemark fixture.

Fig. 5 Two standard Brånemark fixtures are placed in the left-side first molar area of the mandible. Arrow indicatesthe exposed thread of a fixture.

Fig. 4 (a) Cavity in the maxillary sinus is packed with bonechips; (b) labial view of veneer graft fixed with a mini-screw.

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(10). There are many risk factors that affect survival rates,and the most significant ones have yet to be clearlyidentified (4).

In combination with implant treatment, most authorsreport using only one or two types of bone graft, in eitheror both jaws. The case reported here is unusual, becausefour different types of bone graft were used. This is becausethe patient had requested full bridge prostheses to beinstalled in each jaw to support many implant fixtures. Toprepare for this, a variety of problems in both jaws had tobe treated: significant bony defects, thin and narrowalveolar ridges, and a lack of alveolar height. In such cases,other authors have reported using a sinus bone graft on bothsides of the maxilla (11). However, in this case there wasnot enough graft material to apply this technique. Anotheralternative is a Le Fort 1 osteotomy using the sandwichtechnique with simultaneous placement of fixtures toattach the graft to the residual bone. However, it is difficultto correctly align the implanted teeth following thisprocedure and lower implant survival rates have beenreported compared with other grafting techniques (12). Forthese reasons, a combination of veneer, inlay and sinus bonegrafts was selected for this case, to provide the mostsuitable solution for each problem area and to increase thelikely survival rate of the implants. Because of thecomplexity of the procedure, special attention was paid totreatment planning and a satisfactory result was obtainedfor the patient.

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Fig. 7 An additional implant fixture is placed in the maxilla,at the left-side canine area. Arrows indicate theaugmented bone volume at the area of the veneergrafts.

Fig. 8 Three years following placement of the prostheses:(Above): Intraoral view showing full arch prosthesisin the maxilla and two bridge-type prostheses in themandible. (Below): Panoramic X-ray film showingeight fixtures supporting the full arch prosthesis in themaxilla, and two fixtures on each side supporting thebridge-type prostheses in the mandible.

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