3D Character Artist and Sculptor Jim Morren has unveiled a realistic-looking mouth model with a simple rig that allows the artist to tweak jaw and tongue movements. According to the artist, the model has 670k tris and was made in Blender. The tongue rig consists of six joints, allowing for almost infinite possibilities in terms of tongue movements.
The creator also plans to make the project commercially available in the near future, so we highly recommend visiting Jim's Twitter page if you are interested in adding this outstanding model to your characters.
And here are some viewport renders shared by the artist:
