Fabrication of a Monolithic Computer-Aided Design (CAD)/Computer-Assisted Manufacturing (CAM) Zirconia Crown Adapted to the Clasp of an Existing Removable Partial Denture

This case report illustrates a technique for fabricating a monolithic computer-aided design (CAD)/computer-aided manufacturing (CAM) zirconia crown by reproducing the morphology of a provisional restoration that had been adapted to the clasp of an existing removable partial denture. A 69-year-old patient presented after endodontic treatment of the mandibular right first and second premolars, which served as abutments for a removable partial denture with a double Akers clasp. To achieve optimal clasp adaptation, occlusal contacts, marginal fit, a rest seat, a guide plane, and undercut areas were intentionally incorporated into the provisional restoration. Models of the abutment teeth, provisional restoration, and opposing dentition were fabricated. A definitive cast was scanned with a digital scanner, and the datasets were superimposed to design and fabricate a monolithic zirconia crown. The crown demonstrated excellent clasp adaptation upon placement. Over a four-year follow-up period, denture movement was minimized, abutment teeth remained unaffected, and periodontal tissues remained stable. This case highlights the clinical effectiveness of using a provisional restoration incorporating clasp adaptation as a guide for the CAD/CAM-based fabrication of definitive monolithic zirconia crowns for abutment teeth.