I designed this from scratch, but inspired by another model that didn't quite satisfy my itch... pun intended! ;)  I added actual teeth to dig into an itch.  Now you can take this anywhere and vanquish your itches to hades!  

I also added filets, better rotating joint, and a barrel grip. Print with 0.2 Layer height for best results.

Original model for inspiration:

Foldable Back Scratcher by Linabe | Download free STL model | Printables.com