Strain measurement setup of compressively loaded mandible model with teeth and compensations

Abstract

In this study, the setup for strain measurement of loaded mandible model with teeth and compensations is presented. During mastication, bite forces exert compressive loads on mandible and teeth. If compensations are present in a patient, failure might occur on tooth-compensation contact due to inadequate processed tooth design resulting in uneven strain distribution. Difference in hardness of teeth and compensations has an additional impact on failure at the location of contact. Obtaining strain field underneath the teeth in ‘’in vitro’’ measurement is substantial in predicting possible failure. Strain field was measured using contactless optical 3D system ARAMIS 2.0.Aset consisting of two accurately correlated cameras allows recording of relative movement, based on which the strain field was obtained. Proper calibration of the device is substantial for acquisition of results. Mandible models are manufactured using additive technology, allowing for versatile and repeatable results compared to previous researches which included cadaver mandible models. Compensation caps of different design are all made of CoCrMo alloy. Loads are transmitted through a vise, in a force range of 0-150N. Dynamometer is used for applied force measurement. Developed experimental setup allows for application of different cap designs on different set of teeth. Results show how this setup enables comparison of influence of different shapes of compensation and teeth on strain distribution.