What's the difference between audiphone and dentiphone?
Audiphone
Definition:
(n.) An instrument which, placed against the teeth, conveys sound to the auditory nerve and enables the deaf to hear more or less distinctly; a dentiphone.
Example Sentences:
(1) The invention of the Audiphone triggered the development and sale of a number of similar devices that had considerable popularity until the invention of the carbon-electric hearing aid in the early 1900s.
(2) In 1879, the Audiphone, a hearing fan that operated by bone conduction, was patented.
Dentiphone
Definition:
(n.) An instrument which, placed against the teeth, conveys sound to the auditory nerve; an audiphone.