抄録
Purpose: The purpose of this study was to apply in-vivo modal analysis to the maxillary dentition of the maxillectomy patient using obturator prostheses which were different in lateral wall height of the bulb: specifically a high type (H type), middle type (M type), and low type (L type).
Methods: The left central incisor was struck with an impact hammer, and the response at each measurement point was detected using a Laser-Doppler vibrometer. The transfer function was then obtained from each measurement point using a fast Fourier transform analyzer. Finally, a computer analysis and simulation were performed based on the measured transfer functions to obtain the natural frequency, modal shape decay rate (DR), and maximum displacement (MDP).
Results: The results showed that the natural frequency was different between with and without obturator prostheses, that the modal shapes with M and L type obturator prostheses are more suitable than that with H type. The DR of the maxillary dentition with the L type was significantly higher than that with the H or M types, and the MDP of the maxillary dentition with an obturator prosthesis was significantly lower than without an obturator prosthesis.
Conclusion: From the standpoint of vibratory characteristics, the L type obturator prosthesis is the most suitable bulb design for the patient of the three types obturator prostheses. This is the first report to apply in-vivo modal analysis to the maxillary dentition of the maxillectomy patient using obturator prostheses and clarify the vibratory characteristics of the dentition.
