A living hinge, by definition, is made from the same material as the two pieces it connects. I actually made that statement backwards. It technically isn't, but basically is... if that makes sense. Since it isn't the same material it's just a *regular* hinge.

As I have said, if it only needs to survive a hundred or so cycles then it's perfectly fine. If you need more than that AND a rigid material for the rest of the case, then a living hinge isn't the answer for a 3d printed part.