Effect of internal hexagonal index on removal torque and tensile removal force of different Morse taper connection abutments.

Statement Of Problem: The maintenance of the mechanical stability of implant-abutment connections is relevant to the clinical success of implant-supported restorations. However, the reduction in the conical area of abutments with an internal hexagonal index may result in a biomechanical disadvantage in Morse taper connections.

Purpose: The purpose of this in vitro study was to evaluate the influence of an internal hexagonal index on the removal torque and tensile removal force of different Morse taper connection abutments submitted to thermomechanical cycling.

Fracture Strength of Implant-Supported Ceramic Crowns with Customized Zirconia Abutments: Screw Retained vs. Cement Retained.

Purpose: To compare the fracture resistance before and after cyclic fatigue assays of ceramic crowns with customized zirconia abutments when screw retained and cemented onto implants.

Materials And Methods: The sample of this study consisted of 40 ceramic crowns with zirconia infrastructure fixed onto external hexagonal implants. The crowns were distributed into two groups (n = 20): Screw-retained and cemented crowns.