As early as 1859, Johann Nepomuk Czermak (1828–1873) developed an artificial larynx and thus laid the foundation for prosthetic voice rehabilitation following total laryngectomy. Czermak described the case of an 18-year-old girl with complete laryngeal stenosis who was able to produce a pseudo-whispering voice. In an attempt to increase the loudness of the patient’s voice, Czermak routed the flow of air from the lungs into the lower oropharynx. In 1869, he developed the first artificial larynx.
Source: Extract from article