A Full Digital Workflow for the Duplication of an Existing Implant Retained Overdenture Prosthesis: A Novel Approach

The purpose of this clinical case report is to describe a fully digital workflow for the duplication of an existing implant retained overdenture, highlighting the benefits of digitally fabricated dentures. The patient presented with an existing mandibular implant retained overdenture on Locator attachments that needed to be replaced. The existing overdenture was duplicated/scanned with the use of an intraoral scanner and was 3D printed using acrylic resin. This resin duplicate was sectioned in the midline and served as a unilateral record base to digitally record maxillo-mandibular relationship. The occlusal relationship was scanned unilaterally with the record base (sectioned duplicate) in place, and the procedure was repeated for the opposite side. All scans (edentulous, bite registrations and preliminary scan) were superimposed and the software managed to position and stich everything together. A try-in copy denture (ProArtCAD Try in, Ivoclar Vivadent AG, Schaan, Liechtenstein) was milled in order to imitate the conventional wax teeth try-in. A definitive milled overdenture was fabricated and delivered. A reinforcing polyetheretherketone mesh was fabricated, utilizing computer assisted design/computer assisted manufacturing technology and was incorporated into the pre-designed customized space into the polymethylmethacrylate base, using indirect light-polymerized nano-filled composite resin (crea.lign; bredent GmbH & Co. KG). Occlusion was verified and the patient was instructed oral hygiene, home maintenance and was informed for the required recall visits.