Lab Tribune Asia Pacific No.1, 2017

22 TRENDS & APPLICATIONS Lab Tribune Asia Paciﬁc Edition | 12/2017 14 15a 15b 15c 16a 16b 16c 17a 17b 17c 18a 18b Fig. 14: A PVS wash impression was made of the mandibular arch, capturing the positions of the Locator attachments and the gingival contours and vestibules.—Figs. 15a–c: The laboratory produced wax set-ups for try-in. The maxillary set-up included temporary cylinders so that the set-up could be attached to the implants during evaluation. The mandibular set-up included recess wells so that it could be seated over the Loca- tor attachments and soft tissue.—Figs. 16a–c: The maxillary and mandibular wax set-ups were tried in to evaluate it, aesthetics, occlusion and function.—Figs. 17a–c: Individual sections of the implant veriication jig were seated and luted together before being picked up in the open-tray inal impression, which was made using a custom tray and Capture PVS material (Glidewell Direct).—Figs. 18a & b: The inal mandibular implant overdenture was designed to seat over Locator attachment analogues situated in the mandibular cast. This would allow the overdenture caps that engage the Locator attachments to be picked up chairside. —Figs. 19a & b: CAD software was used to design the deinitive prosthesis for the patient’s maxilla based on the inal impression and approved wax set-up. Access holes were created in the precise positions needed for passive it.—Figs. 20 a & b: The provisional implant prosthesis was milled and seated on the master cast to verify proper it, as well as the interocclusal relationship with the opposing implant overdenture. on their speech and masticatory capabilities. For this reason, it is important to make every effort to ensure that the patient leaves with functional appliances in place. Thus, conventional dentures were fabricated from preliminary im- pressions in advance of the surgi- cal appointment for modiication and delivery after placement of the implants (Fig. 6). Suficient primary stability having been achieved, the Inclu- sive Tapered Implants placed in the patient’s maxilla could be im- mediately loaded. Thus, the max- illary denture was trimmed and modiied chairside to connect to the multi-unit abutments through temporary cylinders (Figs. 7a & b). This would satisfy the patient’s de- sire to leave the surgical appoint- ment with a ixed, fully functional maxillary prosthesis in place. Note that the two most distal mo- lars were removed to minimise the cantilevers and the forces transmitted to the implants dur- ing osseointegration. Healing abut- ments were placed on the mandib- ular implants to begin developing the transmucosal passages. The mandibular immediate denture was then modiied and relined to seat over the implants during healing. This approach provided the patient with same- day temporary restorations, and he walked out of the ofice with properly functioning teeth for the irst time in many years. The ef- fect this had on the patient’s com- fort, function and appearance was immediate and profound (Figs. 8a & b). The inal radiograph taken after seating the temporary appliances conirmed excellent positioning of the implants (Fig. 9). The patient returned after 14 weeks of healing for stability of the implants and health of the soft tissue to be evaluated. Removal of the temporary appli- ances revealed excellent tissue health around the healing abut- ments of the mandible and mul- ti-unit abutments of the maxilla (Figs. 10 a & b). Polyvinylsiloxane (PVS) impressions were taken to begin the restorative process (Figs. 11a –c). Because multi-unit abutments and healing abutments were placed on the day of surgery, the restora- tive process began above the tissue level, without any need for second- ary surgery or anaesthesia. The re- storative protocol for both pros- theses included wax rims and set- ups, which the laboratory produced on the working casts fabricated from the impressions (Figs. 12 a & b). The maxillary wax rim incor- porated temporary cylinders through which screws could con- nect to the dental implants. The mandibular wax rim was designed to seat over Locator attachments. At the next appointment, the wax rims were seated, the jaw rela- tionship was recorded using a con- ventional denture technique and a bite registration was taken (Figs. 13a & b). A PVS wash impres- sion of the mandibular arch was also taken with the wax rims and Locator impression caps in place (Fig. 14). This would aid the labora- tory in designing an overdenture that fully rested on the tissue in- stead of the implants. The case was returned to the laboratory, and wax set-ups were produced (Figs. 15a–c). During the try-in ap- pointment, the wax set-ups were evaluated to conirm the vertical dimension of occlusion, interoc- clusal relationship, phonetics, aes- thetics, midline, arrangement of the teeth, tooth colour and shape, in- cisal edges and function (Figs. 16a–c). After inal approval of the wax set-ups, the restorative protocols for the two prostheses diverged, as the laboratory moved directly to the inal implant overdenture from the approved wax set-up, while the process for the BruxZir Full-Arch Implant Prosthesis in- cluded an implant veriication jig, custom inal impression and provi- sional implant prosthesis. These extra measures were taken to make absolutely certain that the deinitive prosthetic design was ac- curate before milling the inal res- toration from monolithic zirconia. The implant veriication jig was at- tached to the implants so that a precise inal impression could be taken (Figs. 17 a–c). The custom tray provided by the laboratory was illed with PVS material and seated over the implant veriication jig. As the PVS material set, the relative positions of the implants repre- sented by the veriication jig re- mained ixed, ensuring an ex- tremely accurate inal impression. The approved wax set-ups and inal maxillary impression were returned to the laboratory so that the inal mandibular implant overdenture and maxillary provi- sional implant prosthesis could be produced. The inal mandibular appliance was fabricated on the master cast and included recess wells in which metal housings with overdenture caps would be cured chairside (Figs. 18a & b). These denture caps provide re- tention and stabilise the pros- 19a 19b 20a 20b

Lab Tribune Asia Pacific No.1, 2017

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