restorative art
TRANSCRIPT
Surface Bones of the Cranium
Geometric form of the normal skull
Oval from three views (front, side, and
crown)
Variations of form due to enlarged width
or length
The width is approx. 2/3 of the length
At birth – facial portion is about 1/8 of the
area of the cranium
Adult – the facial portion is about ½ the
size of the cranial area
Male and Female Skull Comparison
Thicker walls
Muscular ridges
pronounced
Eminences more
prominent
Higher vertex
Upper/lower jaws and
teeth larger
Thinner walls than male
Muscular ridges less pronounced
More rounded
Lighter and smaller
Cranial capacity 10% less than that of the male
Smoother facial bones
Male Female
Surface Bones of the Cranium
Surface Bones of the Cranium
Changes resulting from loss of teeth
Reduction in the size of upper and lower
jaws
Alteration of the angles of the jaws
Reduction of the vertical length of the
face
Surface Bones of the Cranium
Occipital bone (1)
Base/back of the skull
Has the foramen magnum Permits entry of the
spinal cord and used in decapitation restorations
See figure 3 regarding eminences and occipital protuberance
Surface Bones of the Cranium
Parietal bones (2)
Form the superior
portion of the sides
and back and posterior
2/3 of the roof
Forms the widest part
of the cranium at the
parietal eminences
Note location
anatomically in regard to
the ear
Surface Bones of the Cranium Temporal bones (2)
Located inferior to the parietal bones and anterior to the occipital bone
The squama is the vertical portion of the temporal bone
Four anatomical structures for accurate location of the ear (see figure 4 pg. 38)
External auditory meatus
Mandibular fossa
Zygomatic arch
Mastoid process
Surface Bones of the Cranium Zygomatic arches (2)
Location – lowest part of the squama; directly superior to the ear passage and extends anteriorly to the cheekbone
Two restorative values
Establish widest part of the face
Locate correct position of a modeled ear
Mastoid processes (2)
Location – on the undersurface of the temporal bone
Helps to locate the posterior lobe of the ear
Surface Bones of the Cranium
Frontal bone (1) Location – forms the
forehead and the anterior portion of the roof of the skull
Surfaces Vertical – (forehead) from
the eye sockets to the frontal eminences
Horizontal –(crown,vertex) from the frontal eminences superiorly to the parietal bones
Eminences of the frontal bone Frontal eminences (2)
Supraorbital margins (2)
Superciliary arches (2)
Glabella (1)