I’d second the use of resin designed for this purpose. Just about any thermoplastic you can print with (except PEEK maybe, and not many printers print this) will deform at the temps you’ll want to autoclave, so I’d say FDM printing is out. Polymerized resin should handle this much better and should also have a smoother surface with less gaps for bugs to hide in. Quite a bit more expensive than FDM but that’s medicine I guess.
Formlabs resin can be printed on any SLA or DLP style printer; Formlabs will most likely recommend the Form2, which is the printer I use. I highly recommend it.
I think this is something you’re going to have to experiment with. Radiation (Gamma or E-Beam) will cause embrittlement and color changes in most plastics as there’s a lot of cross linking of polymer structures. Some people tint polycarbonate plastic an ice blue color because it will turn a sickly yellow otherwise.
I can’t offer anything about Ethelene Oxide except it’s not very practical in small batches, and autoclave is probably not an option for any thermoplastic you can print.
As others here have said, SLA or DLP is far better than FDM printing if you want to reduce surface defects. FDM will leave large spaces for contaminants and bacteria to grow within, but the resin produces a much smoother surface at a microscopic level.
Hi, I know for a fact that you can use PA2200 which is a nylon powder used on EOS Printers. This material can be sterilised, using various methods. Definitely worth looking into, but you may want to have a look around because if it is going to be in contact with an open wound you will want to make sure the manufacturers have the relevant certificates and conform to standards.