They are characterized by presenting surfaces of contact that are generally very extended, rough, and interlocked with each other.

They can adopt three classic types: dented, harmonic, and squamous.

The squamous type is given by the union of the zygomatic bone with the zygomatic process of the temporal bone.

The fibrous joints of the craniofacial region are classified into four types: dented, scaly, flat, and squamous.

The contact between the upper edge of the vomer and the body of the sphenoid bone is an example of harmonic suture.