Utilizing Reverse Scan Bodies for Immediate Provisionalization of Full Arch Prosthesis

LCDR Eunice Lee, DMD, DC, USN; Laleh Abdolazadeh, DDS, FACP, DC, USN; Stacy Yu, DDS, FACP, DC, USN

Naval Postgraduate Dental School, Bethesda, MD

This case report presents an extraoral scanning technique involving reverse scan bodies to capture implant positions, register soft tissue, and facilitate the design and fabrication of a monolithic immediate full arch prosthesis.

A 58 year old male presented with an edentulous maxilla and existing mandibular ISFCD. Digital wax-ups for both arches were tried in and subsequently, new prostheses were fabricated.  A dual arch scan protocol was completed for implant planning.  Duplicate maxillary denture was used as an out-of-bounds guide and alveolectomy guide. Out-of-bounds guide used to pick up temporary cylinders.  A second duplicate denture captured soft tissue around healing caps, OVD, and jaw relation record. Reverse scan bodies were attached to both duplicate dentures and scanned using a bench top scanner. Scans were imported into a computer-aided design software and merged with the same digital waxup. Provisional prosthesis was designed, milled, finished and polished. Maxillary immediate full arch prosthesis and mandibular interim ISFCD delivered with minimal clinical adjustments.

Reverse scan bodies have been utilized in extraoral scanning to simulate a traditional back-pouring technique used in analog workflows. This case presentation demonstrates an alternate use of reverse scan bodies for a predictable and effective approach to immediate provisionalization of a full arch prosthesis. This protocol eliminated the necessity for an intraoral pick-up of an immediate prosthesis. Consequently, a monolithic full arch provisional with superior structural integrity and predictable occlusion was manufactured and delivered.