"Mmm, not really. Most mammalian species only have a couple sets of teeth. First the baby ones, then the adult versions that replace the original set later. At which point, it's best for the owner of said teeth to not lose them, because they won't grow new ones.

"New feathers, on the other hand, grow in to replace damaged ones all the time. With said molting also featuring at times, like when the babies lose their original feathers to grow in the adult ones that will help them fly in the first place."