I ran into many issues trying to print the original design by Inhuman Species, so I ended up merging some pieces together in MeshMixer and it printed perfectly.
Note that it took me a while to remove all the supports and sand the prints.
* The file "top" is made of the skull files (skull_part_01 / skull_part_02 / skull_part_03).
* The file "bottom" is made of the mandible files (mandible_part_01 / mandible_part_02).
* Both teeth files should be scaled to 110% so that they can fit the holes better.
EDIT:
Inhuman_Species seems to have removed his model from Thingiverse, so I am adding the teeth here. Keep in mind that it may be likely that he asks at some point that I remove my remix.