Mich. Comp. Laws § 205.54ff

Sec. 4ff. (1) The sale to a hospital or freestanding surgical outpatient facility of a prosthetic device for implantation into a human is exempt from the tax imposed by this act. (2) As used in this section: (a) "Freestanding surgical outpatient facility" means a facility licensed under part 208 of the public health code, 1978 PA 368, MCL 333.20801 to 333.20821. (b) "Hospital" means a hospital licensed under part 215 of the public health code, 1978 PA 368, MCL 333.21501 to 333.21571. (c) "Prosthetic device" means a replacement, corrective, or supportive device, other than contact lenses and dental prosthesis, including repair or replacement parts for that device, worn on or in the body to do 1 or more of the following: (i) Artificially replace a missing portion of the body. (ii) Prevent or correct a physical deformity or malfunction of the body. (iii) Support a weak or deformed portion of the body.