[Torque effect of the forces on the terminal abutment in Kennedy Class II cases].

In this research we have compared the properties of force distribution of some retainers which are used in Kennedy Class II modification 1 cases by using photoelastic stress analysis technique. This research has shown that different retainers vary in their ability to reduce stress to abutments. The results showed that the stressbreaker reduced torque to the abutment teeth induced by the denture and contributed to the preservation of the teeth and their supporting structures. When rigid retainers are used, splinting of the distal abutments on the free-end side and restoring of the abutments on the tooth supported side are usually indicated.