mastoid

anatomy

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July 16, 2026

Quick Summary

The mastoid process is a smooth, cone-shaped projection of bone located at the base of the skull, just behind and below the ear. It is a key feature in fossil humans, indicating upright posture. This bony structure is connected to the middle ear cavity and contains air cells.12

The mastoid process is susceptible to inflammation, known as mastoiditis, which typically results from middle ear infections. Symptoms can include pain and swelling behind the ear, and fever. Due to its proximity to the brain and major blood vessels, untreated mastoiditis can lead to serious complications like meningitis or blood poisoning. Treatment usually involves antibiotics, with surgery sometimes necessary.34

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artiodactyl
Specializations of the head
…the skull is called the mastoid, and skulls without such a surface exposure are described as being amastoid. Amastoid skulls are found in most suiform groups (including entelodonts, anthracotheres, and all living suiform groups); mastoid skulls occur in some early suiform groups, oreodonts, and all remaining artiodactyls that have lived…
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…the skull is called the mastoid, and skulls without such a surface exposure are described as being amastoid. Amastoid skulls are found in most suiform groups (including entelodonts, anthracotheres, and all living suiform groups); mastoid skulls occur in some early suiform groups, oreodonts, and all remaining artiodactyls that have lived…
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