Best non-metal nipple bars for surgery?

I usually rock titanium because I need it or my piercings get irritated, but I have to get surgery so I need something like bioplast/bioflex temporarily. For some reason even though I’ve had them pierced for 4 years, the second I take them out they start to close. What’s the least crappy option I have? It’ll probably be in for a week or two until I’m off pain meds and can function enough to go to a piercer to put my titanium ones back in. So not a terribly long time. (It’s shoulder surgery which is why I have to get a piercer to put them in for me)