The temporal bone or the temporal bone pyramid ( pars petrosa [ossis temporalis] , petrosum , outdated also pyramis ) is the hardest bone of the mammalian and human skull and a section of the temporal bone ( os temporale ). It surrounds the inner ear (labyrinth).
Sometimes, especially in animal anatomy, the pars tympanica , which surrounds the middle ear , and the pars mastoidea of the temporal bone are also included in the temporal bone pyramid.
The nervus facialis and the nervus tympanicus , among others, pass through the petrous pyramid . On the front surface (in animals the inner surface) there is a shallow pit for the trigeminal ganglion .
The temporal bone has three important accesses:
- Porus acousticus internus (internal auditory opening): Entry of the facial nerve and exit of the vestibulocochlear nerve
- Stylomastoid foramen : exit of the facial nerve
- Canalis musculotubarius : Canal of the ear trumpet ( Tuba auditiva ) into the middle ear