01: Izchak Barzilay DOS, Cert, Prastha" MS, 01: Murray Arlin DOS, Dip_, Peria" FRCO(C)

ultimately involve implant support for thecomplete maxillary reconstruction.

evaluated future esthetic needs. Afterpatient approval of esthetics and toothposition, an implant placement guide wasfabricated based on the interim removableprosthesis (fig. 1). The guide suggestedimplant positions and angulation forfixtures to be placed in the pontic regions.

Figure 1. An implant placement guidehas been fabricated that showssuggested implant position and

angulation. The guide is supported bythe remaining natural teeth to ensure its

stability during use.

After making diagnostic casts andradiographs, an interim removableprosthesis was fabricated. It was inserted atthe time of pontic removal. This device

Figure 2. Ten implants (shown with fixturemounts) have been positioned using the

placement guide.

The four remaining teeth were kepttemporarily to support the interim

28 The Canadian Tournai of Dental Technology

State of the art implant dentistry demandsrestorations of optimal esthetics as well asfunction. While osseointegration remainsthe basis for success, our patient's increasingexpectations place a new meaning on ourdefinition of success and failure. It isimperative that all the Rlembers of theimplant team (restorative dentist, surgicaldentist, laboratory technician, and patient)effectively communicate and workharmoniously in order to consistentlyachieve optimal results.

A case report is presented thatdemonstrates the restoration of themaxilla. In consultation with all teammembers the following summarizes thetreatment plan sequence utilized for this

patient:1. Fabrication and insertion of the

interim prosthesis retained bymaxillary cuspids and second molars.

2. Fabrication of a surgical pJacementguide based on the patient approvedinterim prosthetic setup.

3. Surgical implant placement.4. Verification of osseointegration and

placement of healing perimucosal

components.5. Extraction of the cuspids and second

molars followed by immediateinsertion of a fixed interim prosthesis.

6. Final prostheses fabrication andinsertion.

7. Supportive care.

Case PresentationA 50 year old female patient presented witha full maxillary restoration fabricated in 3sections. These prostheses were failing dueto periodontal, mobility and prosthodonticissues. Over the next four years, bothposterior bridge segments failed leavingonly the second molars and a mobileanterior fixed partial denture. Both rightand left cuspids were endodonticallytreated and restored but had poor longterm prognosis. After consultation with thepatient, treatment was initiated that would

restoration during healing. A total of tenimplants (fable 1) were placed using theconventional technique (fig. 2). After anuneventful healing period of 6 months, allten implants were uncovered andper-mucosal healing abutments wereplaced. After a soft tissue healing period of4 weeks, an implant level impression wasmade and 3 interim fixed prostheses weremade to restore the implants. The interimrestorations were fabricated from heatcured acrylic (BIOLON) with fiber(RIBBOND) reinforcement. These materialswere attached to the manufacturerscylinders using C&B METABOND as abonding agent between the titaniumcylinder and the acrylic restoration. At thetime of delivery of these restorations, theremaining teeth were extracted and theprostheses were installed. The extractionsites were then allowed to heal for threemonths before final impressions weremade for fabrication of the definitiverestoration. The contour, esthetics and sizeof the definitive restoration was based onthe interim restoration. The definitiverestoration was also made in sections(fig. 3a & 3b) and was made in a directmanner fitting onto the implant surfacewithout intervening abutments (fig. 4).The screw retained porcelain fused to metalprostheses were secured and accessobturated and cotton pellets andcomposite resin (fig.S).

Figure 4. Radiograph shows directcontact of the prosthesis with the

implant. No abutments were used in theprosthetic restoration of the ten implants.

Figure 5. Occlusal view ofthe maxillashowing the three prostheses in place.The anterior prosthesis restores the six

anterior teeth. Composite resin has beenused to obturate the screw access holes.

DiscussionThis case presentation illustrates theinterdisciplinary communication andtreatment of a patient. Initial planning ofthe implant site was done by restorativeand technical spedalists. This informationwas conveyed to the surgical spedalist byusing a placement guide. Pre-surgicalconsultation as to implant type,manufacturer, length and diameterprepared all members of the implant teamfor the possible multiple implant types tobe used for this patient.

Ten implants were ultimately placed.They were of different manufacturers,diameter, length and surface characteristic.The diameter of the selected implants werechosen based on the available bone ridgewidth. A minimum of 1 mm of bone wasleft remaining circumferentially aroundthe prepared implant site thus avoiding theneed for osseous ridge augmentationprocedures. While the literature hasdescribed augmentation techniques, themost predictable recipient site is thepatient's pristine bone. If ridgeaugmentation procedures can be avoided,the morbidity, time and cost to the patientis reduced. In this case, the narrow

diameter implants (3.25 mm) weremanufactured from titanium alloy andwere splinted together with neighbouringimplants in the final prosthesis.

The length of the selected implants werechosen to be as long as possible withoutviolating the anatomic structures. Someresearch has questioned if anosseointegrated implant needs to be longerthat 10-12 mm. At the initial placementhowever, the initial stability of the implant,which is critical to aChieve osseointegration,can be maximized by increasing the totalsurface area of the implant placed (i.e.maximum length and diameter).

Osseointegration is attainable not onlywith machined Grade 1 commerdally puretitanium but also with add etchedtitanium, titanium alloy, titanium plasmaspray and hydroxylapatite coated implants.Processes such as blasting, etching andplasma spraying can increase the surfacearea available for osseointegration andaccelerate the osseointegration process.Studies have indicated that roughersurfaced implants may achieve higher earlysuccess rates espedally in poor densitybone. Most manufactures produceimplants that incorporate a machined(relatively smooth surface) along the fulllength of the implant. Newer designs(Osseotite - Implant Innovations) include amachined surface at the coronal aspect ofthe implant with a rougher surface in theapical portion of the implant. This hasbeen done in order to try to incorporate thebest attributes of both surface types whilepotentially minimizing the long termcomplication of periimplantitis.

In the case presented in this article, addetched machined titanium implants wereused where the bone quality was of fair togood density. In the 2.4, 2.5, and 2.6 area'the bone was of poor density and theOsseotite selective surface etched implantwas chosen. The Osseotite implant surfacemay allow for a more favourable outcomein poor density bone.

Once healing had taken place, theinterim prostheses not only establishedesthetics, phonetics and function, but alsotested the osseointegration of the implantsand the oral hygiene abilites of the patient.The interim prostheses were used as thebasis for the final restoration. The patienthad little difficulty adjusting from theinterim restoration to the final restorationand continues to do well to date. Thepatient is seen on a six month basis forprosthodontic as well as periodontal followup. Radiographs are made to evaluate bonechanges and clinical examination evaluatesperiodontal indices, occlusion andprosthesis integrity and function.

Figure 3a & 3b Right and left lateralviews of the posterior restorations

showing proper emergence profile.

30 The Canadian Journal of Dentnl TechnoloilY - Prosthodontists Journal