Technique for achieving a passive framework fit: a clinical case report

The clinical application of a 4-step technique for achieving the passive fit of an implant-supported cast bar or framework is reported. Implant-level transfers were attached, splinted intraorally with pattern resin, picked up in an open-tray elastomeric impression, and used to fabricate a working cast containing implant analogs. A light-cured template was used to verify master cast accuracy. A ceramometal fixed partial denture restoration was fabricated on the working cast with a preliminary try-in of the cast metal framework. A passive prosthesis fit was achieved. Failure to create an accurate working cast can distort the intended fit of a cast framework on the abutments in the patient's mouth. Optimal positioning of the implant analog in the master cast depends on (1) the transfer technique and (2) the ability of the system to maintain precise rotational orientation of the transfer components. The splinted transfer technique developed 20 years ago has sometimes been effective in improving the accuracy of framework fit with external hexagon implant-abutment connections, but it has not been documented with newer implant-abutment connections. Techniques for reestablishing master cast accuracy and correcting the superstructure are presented. The use of the presented technique resulted in a passive-fitting framework.