GAP Australasian-Dentist-Mar Apr 2019

Category 70 AustrAlAsiAn Dentist Lyndon Cooper Mandibular dental reconstruction using the Astra Tech Implant System®EV and SmartFix concept By Lyndon Cooper, DDs. Ph.D. Associate Dean for research & Head of the Department of Oral Biology, university of illinois school of Dentistry Chicago, il Co-authors: Ghadeer Thalji, DDs, Ph.D. Associate Professor, restorative Dentistry university of illinois school of Dentistry Chicago, il Carly Park, DMD Prosthodontic resident, restorative Dentistry university of illinois school of Dentistry Chicago, il lee Culp, CDt sculpture studios Cary, north Carolina t he patient selected to have her mandibular dentition comprehensively rehabilitated using an implantsupportedfixed prosthesis utilizing four implants. Following CBCt-based planning, her teeth were extracted, an alveolectomy was performed, and four Osseospeed eV implants and Multibase eV abutments (smartFix concept) were placed in a tilted anterioposterior configuration to increase distribution according to the rules of ten.1 A CAD/CAM milled provisional was provided at the time of implant placement. After 8 weeks of uneventful healing, a final impression was made and mandibular/maxillary records made using conventional VPs materials. the final monolithic zirconia prosthesis was delivered and detailed supportive therapy instructions were provided. implant position planned in the 3D environment using simplant software, was assured by guided surgery, proper use of Multibase Abutment eV 17 degree in the posterior and the use of an integrated digital workflow involving CAD/CAM milled immediate prosthesis, a novel 3D printed prosthetic guide and the monolithic zirconia implant supported fixed prosthesis. lInICal Figure 1. Intraoral appearance of the pre- treatment dental condition. The remaining five teeth demonstrated a suitable vertical dimension of occlusion in centric relation. The occlusal plane provided acceptable phonetics and aesthetics. Figure 2. Panoramic radiographic image demonstrates the dentoalveolar status when the patient initially was presented. The failed posterior fixed dental prosthesis was removed prior to definitive treatment planning. Figure 3. Implant treatment planning was performed in Simplant software. Proposed position of the teeth in occlusion and the estimated position of anterior implants (OsseoSpeed EV) and posterior implants (OsseoSpeed Profile EV) is revealed within the confines of the proposed final prosthesis. Figure 4. After surgical placement of implants and alveolectomy using a pilot guide approach, 17 degree Multibase Abutment EV were placed and torqued to 25 Ncm. Anteriorly, straight Multibase abutments EV were used. The PEEK abutment holder is flexible and can be used to avoid the tongue and cheek and to confirm parallel alignment with the other three abutments. Figure 5. Multibase EV Temporary Cylinders were placed onto the abutments using the Multibase EV Bridge Screws. The cylinders were filled with VPS material to protect the screws. Note: Clinician’s choice of opaque material. Figure 6. Polymerisation sleeves were placed on each abutment below the designated finishing line to protect the freshly sutured incision line. The CAD/CAM milled PMMA provisional is sitting loosely over the Multibase EV Temporary Cylinders, later to be positioned in correct relation to maxilla.