instead of hearing sleeve, perhaps 'tooth' version of bone conductor to transmit 'missing frequencies' [1] [1] : https://newatlas.com/hearing-aid-tooth/14042/

instead of hearing sleeve, perhaps 'tooth' version of bone conductor to transmit 'missing frequencies' [1] [1] : https://newatlas.com/hearing-aid-tooth/14042/ https://newatlas.com/hearing-aid-tooth/14042/