Cranial and Facial Bones I: Ethmoid, Sphenoid, Temporal Bones

1. 📌 Essentials

• The ethmoid bone is unpaired, located in the anterior skull base, forming part of the nasal septum and medial orbit walls.
• The sphenoid bone is a complex, butterfly-shaped bone at the skull's base, connecting cranial bones and forming part of the sella turcica.
• The temporal bone is situated at the skull's sides, comprising squamous, mastoid, and petrous parts, protecting hearing and balance organs.
• The ethmoid joins the frontal, nasal, and sphenoid bones, linking anterior and middle cranial fossae with nasal structures.
• The sphenoid articulates with all neurocranial bones, acting as a central "keystone" at the skull base.
• The temporal bone includes critical landmarks like the zygomatic process, mastoid process, and styloid process; important in attachment and neurovascular passage.

2. 🧩 Key Structures & Components