Why is the sphenoid bone considered the keystone of the cranium quizlet?
Why is the sphenoid bone considered the keystone of the cranium quizlet?
Keystone to the cranium because it articulates with all other cranial bones. Bat-shaped portion sof the sphenoid anterior to the sella turcia. Portion off the sphenoid seen exteriorly anterior to the temporal and forming a part of the eye orbits.
Which bone is considered the keystone of the face?
maxilla
Which bone serves as the keystone in the architecture of the cranium?
sphenoid
Why is the sphenoid bone important?
Sphenoid bone has many essential functions. It helps form the base and lateral sides of the skull in combination with the orbital floor. Its many articulations with other bones give the skull rigidity. It is an attachment site for many of the muscles of mastication.
What is the purpose of the sphenoid sinus?
Sinuses are air-filled sacs (empty spaces) on either side of the nasal cavity that filter and clean the air breathed through the nose and lighten the bones of the skull. There are four paired sinuses in the head.
What are the main features of the sphenoid bone?
The sphenoid bone is said to be ‘butterfly-shaped’. It consists of a body, paired greater wings and lesser wings, and two pterygoid processes….It contributes to three parts of the facial skeleton:
- Floor of the middle cranial fossa.
- Lateral wall of the skull.
- Posterolateral wall of the orbit.
Where is the sphenoid process?
The sphenoid bone is an unpaired bone of the neurocranium. It is situated in the middle of the skull towards the front, in front of the basilar part of the occipital bone. The sphenoid bone is one of the seven bones that articulate to form the orbit….
| Sphenoid bone | |
|---|---|
| TA2 | 584 |
| FMA | 52736 |
| Anatomical terms of bone | |
How thick is the sphenoid bone?
The sphenoid bone lies at the base of your skull, and in this bone is a small, cup-shaped depression called the sella turcica (“Turkish saddle”). Lying in this depression is a round ball of tissue, about 1.3 cm (0.5 in) in diameter, called the pituitary gland or hypophysis (Figure 1.9).
What is unique about the sphenoid bone?
Being so centrally located, the sphenoid bone acts somewhat as a bone of transition, allowing various vessels and nerves to pass through its many foramen. What’s particularly unique about the sphenoid bone, is that on its cranial surface, the body has a deeply concave surface called the sella turcica.
What muscles attach to the sphenoid bone?
The sphenoid bone is an attachment point for multiple muscles:
- Lateral and medial pterygoid muscles.
- Lateral rectus muscle.
- Pterygoideus externus muscle.
- Tensor veli palatini muscle.
- Sphenomandibular ligament.
- Temporalis muscle.
- Superior pharyngeal constrictor muscle.
Is sphenoid a facial bone?
Variations. Elements of the cartilaginous viscerocranium (i.e., splanchnocranial elements), such as the hyoid bone, are sometimes considered part of the facial skeleton. The ethmoid bone (or a part of it) and also the sphenoid bone are sometimes included, but otherwise considered part of the neurocranium.
Which two bones are not connected by a suture?
Sutures of the Skull: The bones of the skull, with one pair of exceptions, are joined together by immovable fibrous joints called sutures. (See Fig. 6-7 and 6-8.) The exceptions are the jaw joints, the movable synovial joints between the mandible and the 2 temporal bones.