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Dental TribuneAsia Pacific Edition | 3/2016 06 TRENDS&APPLICATIONS Careful planning is indispensable in the treatment of an edentulous jaw with implant-supported restorations. Theaxesandpositionsoftheimplants must correspond to the given biolog- ical, mechanical and aesthetic condi- tions. In situations in which severe bonerecessionhasoccurred,thework of the dental team has to involve the reconstruction of the dental and the gingival tissue. The flawless recon- struction of gingival tissue requires sound teamwork, as well as excellent materials and exceptional skill. Layer- ing with the light-curing laboratory compositeSRNexco(IvoclarVivadent) takesthisproceduretoanewlevel. A 37-year-old female patient presented to our practice with her teeth and the surrounding bone structure in very poor condition (Figs. 1 & 2). Numerous teeth were missing from both the upper and lower jaws. In addition, the upper jaw showed considerable bone and gingival resorption. The pa- tient wished to have her teeth restored to regain an attractive ap- pearance. Owing to the extensive damage, complete restoration of both jaws with implants was indi- cated. Surgical phase Owing to the sufficient bone structure in the lower jaw, this part of the mouth could be restored at once with four immediately load- able implants. During the recon- structive phase, the upper jaw had to be treated with a provisional removable denture owing to the atrophied alveolar ridge. The tooth extractions from the upper and lo- werjawwereperformedononeday. At the same time, four mandibular implants were placed and loaded. An immediate denture was seated intheupperjaw. During the osseointegration pe- riod of the mandibular implants, the maxillary bone was reconstructed. The maxillary sinus and the alveolar ridge were augmented in one ap- pointment. At a later appointment, ten implants were placed according to the treatment plan and exposed after six more months. As a result of well-planned soft-tissue manage- ment, adequate firm keratinised tissue had formed. The permanent restorations for the upper and lower jaws were fabricated two months later(Figs.3&4). The determination of the occlusal planeandtheidealincisallineallows the dental arches to be integrated more easily in terms of aesthetics andfunction.Open-trayimpressions were taken with a special plaster (Snow White, Kerr Dental) and un- splinted impression posts. The con- siderable stiffness of the impression material completely immobilised the impression posts, thereby pre- venting any errors in the casting of thestudymodels. An articulator allows the kine- matics of the jaw to be correctly simulated. The goal of this part of the treatment is of a functional na- ture.Itisintendedtoensureoptimal occlusal integration of the restora- tions and the proper jaw move- mentsduringmastication,speaking and swallowing. In this particular case, the maxillary model was posi- tioned with the help of a facebow. Fourimpressionpostswerescrewed on to the implants in order to pro- vide strong support and enhanced reliability. Alternatively, this step can take place directly on the immediately loaded provisional restorations. For this purpose, however, the model has to be mounted in the articulator. In the present case, the masticatory modelwaspositionedincorrectrela- tion to the hinge axis-orbital plane. Subsequently, we adjusted the bite patternsinordertorecordthevertical dimensionofocclusion. The centric relation is regarded as the reference position for adjusting the muscles to the centric and func- tional jaw relation. The mandibular model was mounted in the articula- torwiththehelpofanantagonistjaw relationrecord.Ifthecentricrelation and the vertical dimension of occlu- sion are correct, the immediately loaded provisional restorations can beusedforthispurpose.Therestora- tions have to be immobilised when they are mounted in the articulator. The Artex system (Amann Girrbach) allows the articulator of the dental practice and that of the laboratory to besynchronised. The Ditramax system was used to transfer the precise data on the aesthetic facial axes to the maxil- lary model (Figs. 5a & b). Two axes were marked on the plaster base of the model (vertical and horizontal). The vertical axis represents the midsagittal plane. From the front, thehorizontalaxisisalignedparallel to the interpupillary line and from the side to Camper’s plane. These markings, which should be very closetotheworkingarea,functionas a guide for the dental technician in setting up the teeth. Therefore, the incisallinehasapredictableparallel alignment with the interpupillary line. The incisal axis is aligned par- allel with the midsagittal plane. The Camper’s plane markings indi- cate the alignment of the occlusal plane. All these elements provide a sound rationale for the tooth set-up according to aesthetic and func- tionalprinciples. We selected the tooth shade and the teeth on the basis of the SR Phonares II tooth mould chart (Ivoclar Vivadent). Holding the teeth up against the lips of the patient quickly revealed whether they were in harmony with her facial features. The set-up of the teeth according to the Ditramax markings (Fig. 6) allows the situation to be clinically validated. In this case, attention was given in particular to the aesthetic integration of the dentogingival complex when the patient was smil- ing. The lip dynamics were shown with video clips. The functional cri- teria were also checked. The vertical dimension of occlusion had to be harmoniousinordertoachieveabal- anced lower facial third and proper phonation. WefeltthataCAD/CAM-fabricated titanium framework (NobelProcera, Nobel Biocare) would best fulfil this indication. The double-scan tech- nique allowed the implant model to besuperimposedonthetoothset-up to construct the framework. In the next step, the framework was ma- chined and then tried on the model and in the patient’s mouth (Fig. 7). The cast impression and the high- performance processing systems significantly contributed to provid- ingtheoptimalpassive(tension-free) fit of the framework, which is deci- sive for the long-term success of the restoration. The areas that needed to be built up with gingival materials were blasted with aluminium oxide at 200 to 300 kPa pressure. Subse- quently, the SR Link bonding agent (Ivoclar Vivadent) was applied, fol- lowed by a thin layer of the light- curing SR Nexco Gingiva Opaquer to mask the metal framework. The Opaquer was polymerised and then a second coating was applied and polymerised. The resulting in- hibition layer was removed. Aesthetic composite layering ofimplant-supportedrestorationsinanedentulousjaw A good option for the lifelike recreation of gingival tissue By Drs Patrice Margossian & Pierre Andrieu,France 11 12 13 14 7 8 9 10 5a 5b 6 1 2 3 4 Fig.1:Initialphotographofthepatient.—Fig.2:Extremelypoororalcondition:Theteethcouldnotbesaved.Thealveolarridgeintheupperjawwasconsiderablyatrophied.— Fig.3:Afterboneaugmentation,tenimplantswereplaced.Thephotographshowsthesituationpriortotheprostheticphase.—Fig.4:Fourimplantswereplacedinthelower jaw.Boneaugmentationmeasureswere not necessaryin thiscase.—Figs.5a & b:Recordingof the aesthetic facialaxeswith the Ditramaxsystem.—Fig.6:Thedenture was set upwithprefabricatedteeth(SRPhonaresII).—Fig.7:Try-inoftheCAD/CAM-fabricatedtitaniumframeworkintheupperjaw.—Fig.8:Theground-downcompositeresin areaswereconditionedforreceivingthelight-curinglaboratorycompositeSRNexco.—Fig.9:Applicationofthecolour-saturatedintensivegingivamaterials(SRNexcoPaste IntensiveGingiva).—Fig.10:Theapplicationofvarioustranslucentmaterialsimpartedtheprostheticgingivawiththedesireddeptheffects.—Fig.11:Lifelike,vital,aesthetic— the white and pink aesthetics were optimally imitated.—Fig. 12: The restorations on the implants in the upper and lower jaws.—Fig. 13: Close-up view: the macro- and microstructure of the teeth and the characteristic play of colour of the gingiva is clearly visible.—Fig.14:The complex restoration gave the patient a new lease on life. 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