The frontal bone is made up of three parts. These are the squamous part, the orbital part and the nasal part. The squamous part marks the flat and also the biggest part, and the main region of the forehead. The orbital part is the horizontal and second biggest region of the frontal bone. It enters into the formation of the roofs of the orbital and nasal cavities. The nasal, the smallest, part articulates with the nasal bone and the frontal process of the maxilla to form the root of the nose.