RPD Review Questions

Answer to Question #81


The correct answer is

Incorrect. An I-bar (or any type of retentive arm) can be one component that helps establish 180 degree encirclement of an abutment. Because retentive arms are flexible, they may not be quite as effective as some other components but they still contribute.

Incorrect. Because of their location and their rigidity, minor connectors are very effective contributors to 180 degree encirclement.

Incorrect. Because of their location and rigidity, guide plates are very effective contributors to 180 degree encirclement.

Correct. Open latticework (or any type of denture base retentive element) has no relation to the 180 degree encirclement rule.