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Objectives This study aims to investigate the effect of different occlusal relationships on skull structural and mechanical behaviors through simulation of chewing food. Methods Finite element (FE) skull models of occlusion for Class I, end‐on Class II, and full‐cusp Class II were generated. End‐on Class II and full‐cusp Class II were chosen as mild and severe Class II occlusions, respectively. A simplified food bolus was introduced between the upper and lower dentition of the right molars. Chewing food was simulated in the skulls by moving the mandible. An experiment was conducted to measure strains at selective locations and compared them to the analytical results for validation. Results In the early stages of mandibular movement, masticatory forces predicted from the skull models without food were lower than the skull models with food but increased drastically after occluding teeth full enough. As a result, the relationship between masticatory force and mandible movement shows that there is no significant difference between the skull models with food and without food in the range of human masticatory force, approximately 250 N. In all the cases of skulls including a food bolus, stress was similarly propagated from the mandible to the maxilla and concentrated in the same regions, including the mandibular notch and alveolar bone around the lower molars. Conclusion It is predicted that there is no significant difference of bite force–mandible movement relationships and stress distributions of skull and teeth, between end‐on Class II and full‐cusp Class II models. When simulating chewing activities on candy and carrot, it is also found that there is no difference of masticatory performance between Class II occlusions, from structural as well as mechanical perspectives.

The purpose of this study is to investigate the effect of fire-damaged areas associated with wall width on the axial strength of fire-damaged reinforced concrete (RC) walls. Toward that goal, Finite Element (FE) models of RC walls in real scale are generated with various wall widths of (600, 1500, and 3000) mm and number of heated surfaces such as half-surface, single-surface and double-surfaces. For the analyses, experiments are used to obtain temperature distributions inside the walls depending on the fire-damaged areas, and to validate the FE models. The analytical results show that the axial strength of the fire-damaged wall increases linearly with the wall width, except that the ratios of axial force to wall width showed slightly off from the average for the case of walls heated on half of the surface. Using the axial strength data of fire-damaged concrete walls obtained from the current and previous studies, regression analysis is conducted to estimate axial strength reduction ratios of fire-damaged concrete walls, considering various influencing parameters, such as concrete strength, fire-damaged areas, wall width and height. As a conclusion, multiple linear regression formulations from the regressions analyses are able to estimate axial strength reduction ratios of the fire-damaged concrete walls considering various influencing parameters of the wall size, concrete strength and fire-damaged area and the estimations showed good agreements with the data collected from experiments and FE analyses.

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