Analysis of loaded mandible behaviour using speckle pattern interferometry

Orthognatic surgeons have a requirement for the measurement of stress distribution within the human lower jaw, in order to aid and improve surgical procedures. Validation of finite element modelling data describing mandible behaviour which has previously been attempted using holographic interferometry. Electronic speckle pattern interferometry (ESPI), a whole field non-contact optical technique has been applied to the study of a dry human mandible under load. This technique improves over previous methods by generating discrete quantitative displacement and strain components. The optical analysis of a dry mandible is described, with the results viewed in 'real time' as progressively greater forces were applied on the lower border of the chin, in the upwards (impact) direction with biting boundary conditions included in the experimental model. This has shown that the bone tissue holding the front teeth transmits the forces impacting on the chin, which are absorbed by the basal bone of the mandible.