parietals

The parietals are a pair of bones that form a significant portion of the top and sides of the skull. They are quadrilateral in shape and meet each other at the superior sagittal suture, a jagged line that runs down the midline of the skull. Each parietal bone articulates with several other cranial bones: at the front, it connects with the frontal bone at the coronal suture; at the rear, it joins the occipital bone at the lambdoid suture; and at the sides, it articulates with the temporal bone at the squamosal suture. The inner surface of each parietal bone is concave and displays grooves for the meningeal blood vessels, which protect the brain. Prominent on the outer surface are the temporal lines, which serve as attachment points for the temporalis muscle, a major muscle of mastication. The parietal bones are crucial for protecting the brain and providing structural integrity to the cranium. They develop from intramembranous ossification and are fully formed by early adulthood.