Editing Temporal bone (section)

=== Postnatal development ===
Apart from size increase, the chief changes from birth through puberty in the temporal bone are as follows:
# The [[tympanic ring]] extends outward and backward to form the tympanic part. This extension does not, however, take place at an equal rate all around the circumference of the ring, but occurs more at its anterior and posterior portions. As these outgrowths meet, they create a foramen in the floor of the meatus, the foramen of Huschke. This foramen is usually closed about the fifth year, but may persist throughout life.
# The [[mandibular fossa]] is at first extremely shallow, and looks lateral and inferior; it deepens and directs more inferiorly over time. The part of the squama which forms the fossa lies at first below the level of the zygomatic process. As, the base of the skull thickens, this part of the squama is directed horizontal and inwards to contribute to the [[middle cranial fossa]], and its surfaces look upward and downward; the attached portion of the zygomatic process everts and projects like a shelf at a right angle to the squama.
# The mastoid portion is at first flat, with the stylomastoid foramen and rudimentary styloid immediately behind the tympanic ring. With air cell development, the outer part of the mastoid component grows anteroinferiorly to form the mastoid process, with the styloid and stylomastoid foramen now on the under surface. The descent of the foramen is accompanied by a requisite lengthening of the facial canal.
# The downward and forward growth of the mastoid process also pushes forward the tympanic part; as a result, its portion that formed the original floor of the meatus, and contained the [[Foramen tympanicum|foramen of Huschke]], rotates to become the anterior wall.
# The [[subarcuate fossa]] is nearly effaced.

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File:Gray142.png|1. Outer surface of petromastoid part. 2. Outer surface of tympanic ring. 3. Inner surface of squama.
File:Gray143.png| Temporal bone at birth. Outer aspect.
File:Gray144.png| Temporal bone at birth. Inner aspect.
</gallery>