Management of unfavorable implant positions and angulations in edentulous maxillae with different complete-arch fixed prosthetic designs: A case series and clinical guidelines.

Implant-supported fixed prostheses in the edentulous maxilla can be difficult because of anatomic limitations and high esthetic demand. The choice between cement and screw retention depends on factors such as esthetics, occlusion, retrievability, and passivity. The choice is also often governed by the ability to manage technical or biologic complications. In the edentulous maxilla, because of the bone trajectory and resorption pattern, unfavorable implant angulations may be encountered. In such situations, a conventional screw-retained prosthesis is difficult to design. This article describes the restoration of edentulous maxillae for a series of patients with different complete-arch fixed prosthesis designs. The clinical guidelines, including indications, advantages, and limitations of each design, were discussed.