Rationale for a novel attachment system for implant-supported overdentures.

Purpose: To quantify the effect of support stiffness on the retention forces of telescopic crowns and to evaluate a prototype attachment system incorporating a nickel-titanium element.

Materials And Methods: In the first part of the study, telescopic crowns were fabricated employing standard laboratory procedures. For six combinations of telescopic crowns, the separation force was determined while varying the stiffness of their supporting implants.