A fenestration (36) piercing the otic capsule bone of the cochlea (34) receives a therapeutic appliance, such as a microactuator (78), plug (92), micropump for drug or therapeutic agent delivery, electrode (102), etc. Disclosed are several different ways of achieving a “water tight” seal between the otic capsule bone and the therapeutic appliance. Also disclosed are specific ways of implanting the therapeutic appliance both with and without a sheath (72) lining the wall of the fenestration (36) formed using specialized surgical burrs (122, 124, 162, 164).
