Please activate JavaScript!
Please install Adobe Flash Player, click here for download
ePaper created 2017-05-10, 16:12:25 | version 1.38.0
fixed and removable implant restorations CE article | Fig. 16a Fig. 16b Fig. 16c Fig. 17a Fig. 17b Fig. 17c The maxillary osteotomies were positioned to fa- cilitate an All-on-4 configuration, with the posterior implants tilted to maximise the anterior-posterior (AP) spread, avoid the sinuses and accommodate the patient’s bone limitations (Fig. 3). Osteotomies were created for the placement of four mandibular im- plants, as opposed to the minimum of two required for a Locator overdenture. This would enhance reten- tion of the overdenture while affording the possibility of upgrading to a fixed restoration at a later time. This would satisfy the patient’s desire to leave the surgical appointment with a fixed, fully functional maxillary prosthesis in place. Note that the two most distal molars were removed to minimise the cantile- vers and the forces transmitted to the implants during osseointegration. Healing abutments were placed in the mandibular implants to begin developing the transmucosal passages. The lower immediate den- ture was then modified and relined to seat over the implants during healing. Figs. 16a–c: The upper and lower wax set-ups were tried in to evaluate fit, aesthetics, occlusion and function. Figs. 17a–c: Individual sections of the implant verification jig were seated and luted together before being picked up in the open-tray final impression, which was made using a custom tray and Capture VPS material (Glidewell Direct). Following the creation of the osteotomies, the im- plants were placed (Figs. 4a–c). Inclusive Multi-Unit Abutments (Glidewell Direct) were attached to the maxillary implants, correcting for the divergent an- gulation of the implants. This would both position the restorative platform in a manner that would situate the screw access holes of the eventual prosthesis toward the lingual aspect and allow for a molar-to- molar restoration (Fig. 5). Note that when patients present for treatment with terminal dentition, they are commonly anxious about losing their teeth and the effect this will have on their speech and chewing capabilities. For this reason, it is important to make every effort to ensure that the patient leaves with functional appliances in place. Thus, traditional dentures were fabricated from preliminary impressions in advance of the surgical appointment for modification and delivery following placement of the implants (Fig. 6). This approach provided the patient with same day temporary restorations, and he walked out of the of- fice with properly functioning teeth for the first time in many years. The effect this had on the patient’s comfort, function and appearance was immediate and profound (Figs. 8a & b). The final radiograph taken after seating the temporary appliances con- firmed excellent positioning of the implants (Fig. 9). The patient returned after three and a half months of healing so the stability of the implants and health of the soft tissue could be evaluated. Removal of the temporary appliances revealed excellent tissue health around the healing abutments of the mandible and multi-unit abutments of the maxilla (Figs. 10a & b). Vinyl polysiloxane (VPS) 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 restorative process began above the tissue level, without any need for secondary surgery or anaesthetisation. Having achieved sufficient primary stability, the Inclusive Tapered Implants placed in the patient’s maxilla could be immediately loaded. Thus, the upper denture was trimmed and modified chairside to connect to the multi-unit abutments through tem- porary cylinders (Figs. 7a & b). The restorative protocol for both prostheses included wax rims and set-ups, which the lab pro- duced on the working casts fabricated from the impressions (Figs. 12a & b). The maxillary wax rim incorporated temporary cylinders through which screws could connect to the dental implants. The CAD/CAM 2 2017 27