RPD Review Questions
Both the statement and the reason are true. The rigid metal located above the survey line (height of contour) and closest to the edentulous space is that portion of the rest where it joins the guide plate/minor connector. The tip of the clasp lies in front of the axis of rotation and the clasp will be activated when the extension base moves toward the residual ridge. Thus, the clasp must be flexible to provide stress relief for the abutment.