Historical Background of Bone Conduction Hearing Devices and Bone Conduction Hearing Aids

TLDR

Bone‑conduction hearing has been known since antiquity, with early devices such as teeth stimulators in the Renaissance and carbon‑micophone‑based vibrators in the 20th century, culminating in the first Baha implant in 1977 that spurred subsequent device development. This chapter aims to chronicle the historical milestones that enabled the creation of modern bone‑conduction hearing devices. The authors review these milestones using original documentation to illustrate the evolution of the technology. Since the first implant, successive refinements have produced the current Baha system.

Abstract

During the last 20 years, bone-anchored hearing aids (Baha®) became a familiar solution in the treatment of some types of hearing loss. The aim of this chapter is to present the different historical steps which have permitted the production of this new bone conduction hearing device. The recognition of bone conduction hearing is old and was known at least in Antiquity. During the Renaissance, Girolamo Cardano demonstrated a method by which sound may be transmitted to the ear by means of a rod or the shaft of a spear held between one's teeth: this was the beginning of teeth stimulators to improve hearing, firstly in connection with a musical instrument and then, in the second part of the 19th century, with the speaker. The development of the carbon microphone at the beginning of the 20th century allowed the construction of the bone conduction vibrator placed on the mastoid area, notably supported by eyeglasses since the 1950s. Confronted by various problems, and notably the loss of part of sound in the soft tissue of the external mastoid, the idea to implant the vibrator into the mastoid bone was developed in Göteborg, and the first Baha was implanted in 1977 by Anders Tjellström. From that date, various improvements allowed the development of the actual Baha. These different steps are presented in this study, supported by original documentation.