All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad is His slave and Messenger.
We are not aware exactly of what the change in these features is, but the general rule in regard to cosmetic procedures is that they are permissible if they are done to remove a defect and not just for beautification. In this regard, you may refer to fatwa 87848.
Filler injections fall under the ruling of beautification and are included in its details; because as we learned, they contain a substance that is injected to fill the void in some parts of the body.
Allah knows best.