Please activate JavaScript!
Please install Adobe Flash Player, click here for download

Dental Tribune Middle East & Africa No. 5, 2016

Dental Tribune Middle East & Africa Edition | 5/2016 32 CAD/cam guides were fabricated to ensure placement of the implants in the precise positions called for by the treatmentplan(Figs.5a&b). At the next appointment, the tissue- supported surgical guides were tried in and found to be well-fitting. The fixation pins of each surgical guide were tightened with a surgical index in place to ensure complete, secure seating of the appliances (Fig. 6). A tissue punch was used to provide access to the implant sites, facilitat- ing a flapless surgical procedure that would minimise gingival trau- ma. The osteotomies were created through metal inserts placed in the surgical guides, which precisely con- trolleddrillingdepthandorientation according to the digital treatment plan(Fig.7). Eight BioHorizons® Laser-Lok® dental implants (BioHorizons; Bir- mingham, USA) were placed in each ridge, including 5.7 mm implants in the two distalmost locations of each arch, and 4.5 mm implants in the re- maining sites. After placing healing abutments in the implants, a soft re- line was performed on the patient’s temporary dentures so they could continuetoserveasinterimprosthe- ses for the duration of healing and osseointegration. Four months after surgery, the patient returned to the office so impressions could be taken. Removal of the healing abutments revealed optimal tissue health sur- rounding the implant sites (Figs. 8a & b). Transfer posts were seated to capture the position of the implants (Fig.9).Closed-trayimpressionswere taken of the upper and lower arches DrAraNazarian DICOI(Diplomate International CongressofOral Implantologists) 1857East Big BeaverRoadTroy, Michigan48083, USA drnazarian@premierdentalcenter.com www.michiganreconstructiveimplant- dentistry.com www.premierdentalcenter.com www.aranazariandds.com Figs. 14a & b.The lab digitally produced the custom abutments and verified the design on thesoft-tissuemodels. Figs.18a&b.TheBioTempsprostheseswere triedinandfit thepatient well. Figs. 22a–22c. Retracted frontal, occlusal maxillary and occlusal mandibular views exhibit the excellent esthetics achieved by the im- plantsandfixedPFMprostheses,reconstructing thepatient’sdentitionaswellas thesoft tissue. Fig. 17. Acrylic positioning jigs were used to seat the custom abutments in the pa- tient’smouth. Fig. 21. Final panoramic radiograph illus- trates proper placement and orientation of thedentalimplants. Fig. 15. A diagnostic wax-up was created to assist in the development of the full- archreconstructions. Fig.19.TheinterimBioTempsrestorations wereevaluatedforproperocclusion,func- tionandesthetics. Fig. 16. The BioTemps prostheses were fabricated, and the interocclusal relation- ship was verified on the articulator prior topatient try-in. Fig. 20. Based on the final-approved Bi- oTemps prostheses, the final PFM restora- tionswerefabricatedon themastercasts. Fig. 23. The patient was provided with a nightguard to protect his investment against theforcesofbruxing. using Take 1® Advanced™ vinyl poly- siloxane material (Kerr Corp.; Or- ange, USA, Figs. 10a & b). At the same appointment, thermoformed suck- down impressions were made and a bite registration taken with the pa- tient’s immediate dentures in place, providingthelabwithatemplatefor the definitive design of the PFM res- torations(Fig.11). The lab poured working casts from the VPS impressions of the patient’s edentulous arches and produced wax occlusal rims (Fig. 12). After seat- ing the wax rims in the patient’s mouth and tightening the tempo- rarycylinderscrews,thejawrelation- shiprecordsweretaken(Fig.13).Note that the patient’s vertical dimension had virtually collapsed due to the extensive wear to his teeth. After measuring the distance between the patient’s nose and chin during maximum intercuspation, the lab was instructed to open the patient’s biteby2mm.Next,thelabusedCAD software to design Inclusive® Tita- nium Custom Abutments (Glidewell Europe GmbH; Frankfurt/Main, Ger- many) for both arches based on the scanned working models. The CAD/ CAM-produced custom abutments were seated on the working models so their fit could be verified and they could be used in the development of the definitive prostheses (Figs. 14a & b). Based on the jaw relationship records and the impressions of the patient’s immediate dentures, the lab prepared a diagnostic wax-up to help determine the initial design for thePFMrestorations(Fig.15).Afterfi- nalising the initial design, BioTemps prostheses were fabricated from polymethyl methacrylate (PMMA) material, which is versatile enough to easily accommodate adjustments at the try-in appointment, yet dura- ble enough for provisionalisation (Fig. 16). The working models were sentoutalongwiththecustomabut- ments and BioTemps interim resto- rations for patient evaluation. At the nextappointment,thetitaniumcus- tom abutments were transferred to thepatient’smouthusingtheacrylic delivery jigs provided by the lab (Fig. 17). The custom abutments achieved a precise fit and were thus tightened to the appropriate torque, establish- ing ideal soft-tissue margins and support. Complete seating was veri- fied radiographically, and the screw accessholeswerecovered. Next, the BioTemps prostheses were tried in and exhibited an accurate fit (Figs. 18a & b). The provisional res- torations were attached to the abut- ments using temporary cement, and the phonetics, aesthetics, bite and function were evaluated (Fig. 19). Mi- nor modifications were made to the BioTemps prostheses, and the pa- tient wore the BioTemps provision- als for an interim of four weeks. This trial period was essential in verifying that the patient was happy with the look, comfort and function of the prosthetic designs before the final PFM restorations were fabricated. After patient approval was provided, alginate impressions were made of the BioTemps prostheses. Models of the final-approved BioTemps resto- rations were fabricated from the im- pressions, and a new bite was taken so the definitive prosthetic designs couldbeadjustedaccordingly.Crown & bridge impressions were taken of the final custom abutments in place andwouldbeusedbythelabtopour master models,uponwhichthe final PFM prostheses would be produced. The gingival areas for the final PFMs were marked onto the models of the BioTemps restorations, and the case was returned to the lab along with instructions for final adjustments. The final PFM prostheses were fab- ricated by layering porcelain over a castmetalframework.Pinkporcelain was layered on to form the gingival areasaccordingtothemarkingsindi- catedonthemodelsoftheBioTemps restorations, thus replacing por- tions of the soft tissue as well as the teeth per Dr Misch’s FP3 (Fixed-Pros thesis-3) principles of prosthetic de- sign.6 Because the final prostheses were designed using the models fabricated from the final crown and bridge impressions, a precise fit over the patient’s custom abutments was ensured(Fig.20). At the final delivery appointment, the PFM restorations were delivered over the custom abutments with- out issue. A panoramic radiograph was taken to confirm complete seating (Fig. 21). The final prostheses achieved the exact fit, aesthetics and function that the patient had come to expect after six weeks of wearing the BioTemps provisionals, which ultimatelyservedasthebasesforthe finalrestorations(Figs.22a–c). The patient was ecstatic with the re- sults, which reconstructed his teeth and gingiva, along with his confi- dence and quality of life. A night- guard was produced for the patient to mitigate the impact of his par- afunctionalhabits(Fig.23). Conclusion The predictability of implant treat- mentandtheadaptabilityofrestora- tive materials enable clinicians to provide patients in the most dire of dental circumstances a complete overhaul, reversing the damage that canresultfrommanyyearsofdental wear and neglect. This goes beyond the restoration of oral function by preserving the facial aesthetics that aresofundamentaltotheemotional state and social life of the patient. Provided its life-changing capacity, the fixed full-arch implant restora- tion should be offered to all patients who present with untreatable denti- tion, without prejudging a patient’s situation and the form of treatment that they will ultimately accept. As the precision, cost-effectiveness and prosthetic versatility of implant therapy expands ever further, so does the patient population that is able to receive high-quality treat- ment. Editorial note: Reprinted by permis- sion of ©2015 Glidewell Laboratories, inclusive magazine. The dental lab work in this case was performed by Glidewell Laboratories. A complete listofreferencesisavailablefromthe publisher. Figs.10a&b.Upperandlowerclosed-trayimpressionsweretakenandsent tothelabso workingcastscouldbefabricated. Fig. 13.The patient’s jaw relationship was recordedwith thewaxrimsinplace. Fig. 11. Impressions of the patient’s im- mediate dentures were taken along with abiteregistrationtohelpguidethedesign of thedefinitiveprostheses. Fig. 12. Wax rims were produced by the lab so the patient’s interocclusal relation- shipcouldbedetermined. ◊Page30

Pages Overview