If you want them clean and shiny (and not smelling like rotten meat), soak them in hydrogen peroxide until the blood and tissue dissolves. This usually takes hours to days, depending on the amoint of tissie. To make them white, soak them in 30 strength hair developed for a few days. You'll have super-white, clean teeth to display!

This is way too far down. This is your answer, or at keast a path and not immediate euthanasia. Bloodwork isn't super expensive and the meds are pretty cheap.