The bone compression and the inertia from cochlear fluid or middle ear (ME) ossicles, are generally considered to be important components inducing bone-conducted (BC) hearing. To clarify the bone compression effect on the BC hearing caused by variation of Young’s modulus of skull, two different types of three-dimensional finite-element models were used in this study. The FE models were (1) Isolated cochlea model comprising ME and cochlea containing basilar membrane (BM) and (2) Head model comprising the isolated cochlea structure. The model was validated by comparison of cochlear responses such as BM velocities with those of otosclerosis patients’ clinical data. Additionally, results showed that the bone compression effects on a BC hearing is highly depended on the Young’s modulus of a skull. Also, the bone compression effects could be underestimated at low frequencies in temporal bone experiments, whereas the effects could be overestimated at high frequencies in cadaver experiments.

Three-dimensional CAD models are usually used by designers because of their applications in the areas of CAD/CAM/CAE/CAQ. A desirous trend to create this model, long been studied by scientists globally, is 3D model reconstruction from views. With this method, geometric information can be easily entered as well as using existing 2D drawings. Most of the previous studies used three views, but many of the common parts needed only two views. A flexible reconstruction system that responds to both forms is the subject of this study. The proposed method has been installed and tested by an ADSRX program running on AutoCAD software. The 3D model results have been checked for the compatibility with CAD/CAM systems.

The objective of this study is to verify the accuracy of performing surgery by developing and experimenting orthognathic surgical splints using 3D convergence technology. We performed the computation of the movement of the maxilla on the virtual simulation data for the surgery then designed the surgical splints using 3D CAD. We produced the designed splints and the test object and experimented on them using a 3D printer (accuracy ± 0.025 mm). The subjects were scanned using an optical scanner (accuracy ± 0.01 mm). We then compared and evaluated the simulated data and their accuracy. The evaluation results showed that the mean error range was within +0.313/-0.456 mm (average standard deviation 0.106), which was within the range of ±0.5 mm. These splints did not need for a reference point for external measurement to be set, neither did it need improving of the accuracy nor shortening the operation time. In addition, its advantage is that the amount of bone removal can be known accurately when the maxilla is repositioned.

The mold manufacturing is one batch production that the same process does not repeat. The digital model in software is processed with a real mold fabricated in high performance without error. In this study process planning, and machining simulation software are integrated with a smart machine tool for the mold industry. It reduces the operational complexity to four button clicks after dragging and dropping of 3d model data to fabricate multiple-numbers of graphite electrodes. The smart machine tool fabricated 27 graphite electrodes with minimum interference of humans in 35 hours.