Bones of the Skull (Detailed)

Question 1

Parts of the skull

Answer 1

Divided into 2 parts;
-Viscerocranium (Splanchocranium)
-Neurocranium

Question 2

Viscerocranium (Splanchnocranium)

Answer 2

-Refers to the bones that form the facial skeleton
-Made up of 14 irregular bones
-Can be seen in an anterior view of the skull

Question 3

Neurocranium

Answer 3

Refers to the bones that house and protect the brain

Question 4

Skull definition

Answer 4

Refers to the entire bony framework of the head including the mandible

Question 5

Cranium definition

Answer 5

Refers to the skull without the mandible

Question 6

Calvaria definition

Answer 6

Refers to the skull cap which consists of the upper part of the neurocranium or the superior portions of the frontal, parietal and occipital bones

Question 7

Bones of the viscerocranium

Answer 7

-Nasal bone
-Maxillae bone
-Zygomatic bone
-Mandible

Question 8

Bones of the neurocranium

Answer 8

-Frontal bone
-Parietal bone
-Temporal bone
-Sphenoid bone
-Ethmoid bone
-Occipital bone

Question 9

Nasal bones
(Os nasale)

Answer 9

-Found at the centre of the face
-Two small paired bones
-These bones define the nose, and determine its shape and size
-Superior borders and main bodies form the bridge of the nose
-Inferior borders connect with the nasal cartilage to then form the superior margin of the nasal aperture

Question 10

Maxillary bone (Upper jaw)
Maxilla

Answer 10

-Found upwards/laterally from the nasal bone
-A paired bone consisting of the right and left maxilla which fuse in the midline
-Involved in the formation of the bony orbit, nose and palate
-Holds the upper/maxillary teeth
-Plays an important role in communication

Question 11

Key features of the maxilla

Answer 11

-Infraorbital foramen or foramina (a paired structure)
-Anterior nasal spine
-Has 4 projections; the zygomatic process, the alveolar process, the frontal process and the palatine process

Question 12

Zygomatic process

Answer 12

Articulates with the zygomatic bone on either side of the face contributing to the formation of each orbit

Question 13

Alveolar process

Answer 13

Forms half of what is known as the maxillary dental arch and holds the upper teeth

Question 14

Frontal process

Answer 14

Articulates with the frontal bone and contributes towards the medial border of each orbit

Question 15

Palatine process

Answer 15

-It is a horizontal extension found on the medial side of this bone, so can be seen from an inferior or medial view
-The Palatine process contributes to the roof/hard palate of the mouth as well as the floor of the nasal cavity.

Question 16

Zygomatic bone

Answer 16

-Paired bone found on both sides of the face
-One of the most irregularly shaped bones in the skull

Question 17

Mandible (lower jaw)

Answer 17

-The body is the largest part of this bone and possesses the mental foramina

Question 18

Frontal bone

Answer 18

-Bone that defines your forehead
-One of the bones that encases the brain
-Consists of 3 parts; the squamous part, the orbital part, and the nasal part

Question 19

Squamous part

Answer 19

Makes up the largest portion of the frontal bone encompasses the area of the forehead and houses the frontal sinuses

Question 20

Orbital part

Answer 20

Essentially the part of the frontal bone that contributes to the bony orbit

Question 21

Temporal bone

Answer 21

-Another paired bone
-Form the base of the cranial vault along with this bone right here, the occipital bone, and they also ascend to participate in the lateral walls of the skull.

Question 21

Nasal part

Answer 21

The portion that articulates with the frontal processes of the maxilla and the nasal bones and this is the portion that helps form the root of the nose.

Question 22

Parietal bone

Answer 22

-A paired bone found on both sides of the skull and it forms large parts of the top and sides of your head
-The parietal bones also connect with the temporal bones via the squamosal suture, and with the sphenoid bone via the sphenoparietal suture

Question 23

Sphenoid bone (Wasp bone)

Answer 23

-Makes up most of the middle part of the base of the skull and contributes towards the floor of the middle cranial fossa
-Made up of two important parts- greater and lesser wings

Question 24

Ethmoid bone

Answer 24

-Contributes towards the medial wall of the bony orbit
-In the anterior nasal aperture, there are several structures of the ethmoid bone including the superior and middle nasal conchae and the perpendicular plate

Question 25

What is the bony orbit

Answer 25

-A skeletal cavity that is made up of several cranial structures and surrounds the soft tissue that makes up the eye
-Divided into four main parts – the roof, the lateral wall, the medial wall, and the floor

Question 26

The roof of the bony orbit

Answer 26

Comprised of the orbital surface of the frontal bone and the lesser wing of the sphenoid bone

Question 27

The lateral wall of the bony orbit

Answer 27

Comprised by the orbital surface of the zygomatic bone and the greater wing of the sphenoid bone

Question 28

The medial wall of the bony orbit

Answer 28

-Defined by the orbital plate of the ethmoid bone and the sphenoid bone
-Contributes to the medial wall of the bony orbit along with a few other bony structures such as the lacrimal bone.
-There are some small contributions from other bones including the frontal bone and the maxilla.

Question 29

The floor of the bony orbit

Answer 29

-Anteriorly, the floor is defined by the orbital surface of the maxilla and the orbital surface of the zygomatic bone.
-Posteriorly, it’s defined by the process of the palatine bone