Effects of overdentures upon remaining oral structures.

This study provided the following guidelines in the selection of specific designs for overdenture abutments: 1. The Dolder bar, which exhibits more cross-arch involvement than the Zest anchor, will share the occlusal load across the arch, between the abutments and the supporting structures. 2. The posterior edentulous regions will receive some physiologic stimulation with the Dolder bar, for it shares more stress here than the Zest anchor. 3. The forces on the Dolder bar produce stress directed more apically than that from the Zest anchor. Since this force is better tolerated, use of the Dolder bar may be indicated for a short-rooted tooth with less supporting bone. 4. The greater stress concentrated around the abutment teeth by the Zest anchor makes use of this design in a tooth that is periodontally sound and has a long root structure well imbedded in supporting bone seem logical.