I have designed it to be as compact as possible, but still fit as many styles of toothbrushes as possible. I tested these with 5 kids on a 7 day trip. Not only did these cases survive the abuse, but they performed wonderfully!
Use a section of 1.75mm filament inside the hinge to connect the lid to the base. Depending on your printer/setup, this hole maybe be on the tight side or a bit loose. If tight, drilling out the hole may help. If it is slightly oversized, I suggest melting the end of the filament piece with a soldering iron or lighter.
The following filaments were used in the pictures above: