Voice of Mummified King Henri IV Recreated via 3D Functional Vocal Tract Model

Human voice arises from the glottal source being shaped and modified by the resonances of the vocal tract (VT). Reconstructing this interaction from mummified or surgically altered anatomy poses a significant challenge. In this study, we aimed to recreate the phonatory potential of King Henri IV of France (1553-1610) through a functional three-dimensional (3D) reconstruction of his preserved head and neck, providing insights into vowel production in altered vocal anatomy.

The embalmed head and neck of King Henri IV provided a unique opportunity to model historical phonation. Using high-resolution computed tomography imaging, all craniofacial and cervical structures were manually segmented in ITK-SNAP 4.0 by two independent operators following validated protocols. Mesh refinement was performed in Mesh Mixer® without altering anatomical integrity. Digital reconstruction and anatomical repositioning (including mandibular closure, vertebral alignment, and articulation correction) were achieved in Fusion 360® and reviewed by a multidisciplinary panel. Acoustic simulations were conducted on both digital and 3D-printed models to assess vowel-like sound production.

The physical reconstruction of King Henri IV's head and VT enabled the generation of distinct vowel-like sounds. Initial digital simulations produced vowels comparable to /u/ (F1 = 446 Hz, F2 = 1055 Hz, F3 = 2360 Hz), /a/ (F1 = 582 Hz, F2 = 1556 Hz, F3 = 2557 Hz), /i/ (F1 = 340 Hz, F2 = 2144 Hz, F3 = 2841 Hz), and /œ/ (F1 = 540 Hz, F2 = 1530 Hz, F3 = 2545). The 3D-printed model reproduced /a/ (F1 = 588 Hz, F2 = 1109 Hz, F3 = 2585 Hz) and /u/ (F1 = 427 Hz, F2 = 880 Hz, F3 = 2452 Hz) with realistic resonance patterns producing a comparative vowel chart.

This study demonstrates that combining advanced imaging, digital modeling, and 3D printing can restore plausible phonatory behavior from preserved or altered anatomy. Such interdisciplinary methodology has potential translational applications in phonatory modeling, surgical voice rehabilitation, and laryngeal function research.