title: Application of modal analysis to human subjects: comparison of healthy subjects and cleft lip and palate subjects.
abstract: To evaluate the vibrational characteristics of the maxillary arch, modal analysis was applied to human subjects. Twelve healthy human subjects and 2 cleft lip and palate (CLP) subjects with surgical failure in their cleft area were chosen for this study. The main measurement system was composed of an impact hammer, acceleration sensor, CF-6400 FFT Analyzer, PC-9821Xn personal computer, and Vibrant PC modal analysis software. The measurement points were established on 12 teeth between the upper first molars on both sides of the mouth in healthy subjects, and on 10 teeth in CLP subjects. In all subjects, one distinct resonance peak was observed in each transfer function at each measurement point. All of the transfer functions of a given subject strongly resembled each other in terms of shape. The amplitude and modal shapes of the maxillary arches of all the subjects were obtained by using a curve-fitting function in the software. In the healthy subjects, the maxillary arch expanded outward and shrank inward on vibration with no node after an impact. In the CLP subjects, the phase lag between the large and small segment was distinctly observed after an impact. In this study, the applicability of modal analysis for human subjects was demonstrated.
authors.affiliation: Department of Maxillo-Facial Prosthetics, Graduate School, Tokyo Medical and Dental University, Japan.
authors.forename: L
authors.initials: L
authors.lastname: Du
authors.forename: R
authors.initials: R
authors.lastname: Suzuki
authors.forename: H
authors.initials: H
authors.lastname: Taniguchi
authors.forename: T
authors.initials: T
authors.lastname: Ohyama
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002971:Cleft Lip / Q000503:physiopathology; D002972:Cleft Palate / Q000503:physiopathology*; D003198:Computer Simulation; D003724:Dental Arch / Q000033:anatomy & histology* / Q000502:physiology*; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D008297:Male; D008437:Maxilla; D008954:Models, Biological; D010474:Percussion; D015203:Reproducibility of Results; D014732:Vibration