Final answer:
Functional joints between the skull bones and teeth sockets are gomphosis joints, with periodontal ligaments holding the teeth firmly. Sutures are the fibrous joints connecting skull bones, and both types of joints are classified as synarthroses.
Step-by-step explanation:
The functional joints found between the skull bones and the teeth sockets are known as gomphosis joints. A gomphosis is a type of fibrous joint where the tooth is anchored into its bony socket in the jaw. The teeth are held in the sockets by the periodontal ligament, which is a dense connective tissue that provides a strong, immovable connection. This type of joint is functionally classified as a synarthrosis because it allows for very little to no movement, making it a stable union. Apart from gomphosis, the skull bones are interconnected by another type of fibrous joint called sutures, which also allow for minimal movement and are thus classified similarly as synarthroses.