Transverse bend testing of denture base polymers

A test rig has been designed for transverse bend testing on the Instron machine. The rig is a robust, accurately machined piece of equipment that enables this test to be carried out with accuracy and ease. A range of denture base polymers has been tested under similar conditions to the ISO standard recommendations (ISO/R 1567, 1974), and in this series all the materials except 3 satisfied the criteria laid down in the standard. The specimens were tested in water after 1 month because it has been shown previously that the materials are almost fully saturated at that time (Stafford and Huggett, 1973). Nevertheless, this immersion in water may also weaken the material and this could account for the failure of some materials to pass the standards criteria.