At what age does the anterior fontanelle ossify to form the Bregma?
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At the age of 1.5 to 2 years.
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At what age does the anterior fontanelle ossify to form the Bregma?
At the age of 1.5 to 2 years.
What bones does the lambdoid suture separate?
The occipital bone from the two parietal bones.
What bones does the coronal suture separate?
The frontal bone from the two parietal bones.
Which bone is labeled 'Zygomatic' in the image?
The zygomatic bone.
What is another term for the calvarium?
Skull vault or roof.
What type of joint are the coronal, sagittal, and lambdoid sutures?
Fibrous joint.
What is the vertex of the skull?
The most convex point of the skull vault (calvaria) near the midpoint of the sagittal suture, between the bregma and lambda.
What is located above the zygomatic arch in the Norma Lateralis?
The temporal region.
What passes through the parietal foramina?
Emissary veins.
What is the function of the zygomatico-facial foramen in the zygomatic bone?
It allows the passage of nerves and vessels (N.&Vs).
What is the anatomical position of the squamous part of the occipital bone in the calvarium?
Posteriorly.
What is the parietal eminence?
The most prominent part of the parietal bone and the site of the ossification center of the parietal bone.
What is the Bregma?
The point of meeting of the coronal with the sagittal sutures.
What is the anatomical position of the frontal bone in the calvarium?
Anteriorly.
What is the anatomical position of the parietal bones in the calvarium?
Laterally.
Which four bones form the structure shown in the image?
Frontal, nasal, maxillary, and zygomatic bones.
What is the calvarium also known as?
The top part of the skull and the upper part of the neurocranium.
Which fontanelle is located at the Bregma?
The anterior fontanelle.
What cavities are surrounded by the bones shown in the image?
Two orbital cavities and a nasal cavity.
What bones form the calvarium?
Frontal bone, left and right parietal bones, and squamous part of the occipital bone.
Where is the parietal foramen located?
On each side of the sagittal suture.
What is the canine eminence?
A feature of the maxilla that corresponds to the position of the canine tooth.
What structures are found in the nose related to the zygomatic bone?
Vomer and inferior nasal concha.
What bones does the sagittal suture intervene between?
The two parietal bones.
What is the Lambda?
The point of meeting of the lambdoid with the sagittal sutures.
At what age does the posterior fontanelle ossify to form the Lambda?
At the age of 4 to 6 months.
What does the alveolar process contain?
The sockets of the upper teeth.
What is the canine fossa?
A depression in the maxilla located below the infraorbital foramen and above the canine tooth.
Which teeth are referred to as incisor teeth?
Central and lateral incisor teeth.
Where is the superior nuchal line located?
It is located on the external surface of the occipital bone, running horizontally from the external occipital protuberance.
Which fontanelle is located at the Lambda?
The posterior fontanelle.
What sutures meet at the Lambda?
The lambdoid and sagittal sutures.
What are the two processes of the zygomatic bone?
Frontal process and temporal process.
Which bone contains the lacrimal fossa and groove?
The orbit contains the lacrimal fossa and groove.
What is the anterior nasal spine?
A projection of the maxilla at the lower margin of the nasal cavity.
What is the function of the occipital condyle?
It forms a synovial ellipsoid joint with the first cervical vertebra (atlas), enabling nodding movements of the head.
What sutures meet at the Bregma?
The coronal and sagittal sutures.
How many processes does the maxilla bone have?
Five processes.
What is the alveolar process of the maxilla?
It contains the sockets for the upper teeth.
What is the superciliary arch?
The ridge above the eye socket, where the eyebrows are located.
What is the pterygopalatine fossa?
A small pyramidal space deep to the pterygomaxillary fissure.
What is the name of the suture found in the Norma Occipitalis?
Lambdoid suture.
What is the function of the frontal process of the maxilla?
It articulates with the frontal bone.
Where is the inferior nuchal line located?
It is located on the external surface of the occipital bone, below the superior nuchal line.
What forms the zygomatic arch?
The union of the temporal process of the zygomatic bone and the zygomatic process of the temporal bone at the zygomaticotemporal suture.
What is the location of the intermaxillary suture?
Between the two maxillary bones.
What are the nasal bones?
Two small bones that form the nasal bridge.
What prominence does the zygomatic bone form?
The prominence of the cheek.
Where is the highest nuchal line located?
It is the uppermost of the three nuchal lines on the external surface of the occipital bone.
What are the main features of the maxilla bone?
It forms the upper jaw and contains the maxillary air sinus.
What is the palatine process of the maxilla?
It forms the anterior two-thirds of the hard palate.
What is the frontal air sinus?
An air-filled cavity within the frontal bone.
Which bones form the Norma Occipitalis?
Two parietal bones, occipital bone, and the mastoid part of the temporal bone.
What does the anterior cranial fossa hold?
The frontal lobe of the brain.
Where is the incisive fossa located?
On the maxilla, near the incisor teeth.
What is the lateral boundary of the infratemporal fossa?
Ramus of Mandible.
What is the supraorbital margin?
The upper edge of the eye socket.
Which bone is located below the lambdoid suture in the Norma Occipitalis?
The occipital bone.
What is the nasal bridge?
A saddle-shaped area that includes the nasal root and the lateral aspects of the nose.
What is the mastoid process of the temporal bone?
The mastoid process is a conical prominence projecting from the temporal bone, located behind the ear, and contains air cells that communicate with the middle ear.
What is the Lambda and when does the posterior fontanelle close?
The Lambda is the posterior fontanelle, and it closes at around 6 months.
What does a depressed fontanelle indicate?
A depressed fontanelle indicates dehydration.
What part of the temporal bone is involved in forming the middle cranial fossa?
Petrous part of the temporal bone.
What structure is located in the groove for the optic chiasma?
Optic chiasma.
Which cranial fossa is located at the highest level in the skull base?
The anterior cranial fossa.
What is the frontal eminence?
A rounded elevation on the frontal bone.
What is the center of ossification in the frontal bone?
The primary site where bone formation begins in the frontal bone.
What is the nasion?
The midline point of the junction of the frontonasal suture with the internasal suture.
What is the roof of the infratemporal fossa?
Sphenoid.
What does the term 'sphenoid' mean and from which language is it derived?
'Sphenoid' means wedge-shaped and is derived from the Greek word 'sphenoeides'.
Which part of the sphenoid bone is labeled 'Body' in the image?
The central part of the sphenoid bone is labeled 'Body' in the image.
What is the squamous part of the temporal bone?
The squamous part of the temporal bone is the broad, flat portion that forms part of the side of the skull.
What is the role of the Medial pterygoid plate?
The Medial pterygoid plate serves as a point of attachment for muscles of mastication.
Which bones form the posterior cranial fossa?
Occipital bone, petrous part of the temporal bone, and mastoid part of the temporal bone.
What is the largest and deepest of the three cranial fossae?
The posterior cranial fossa.
What is the function of the cribriform plate of the ethmoid bone?
It contains small foramina that allow the passage of the olfactory nerves.
What structures are found in the posterior cranial fossa related to the occipital bone?
Internal occipital crest and internal occipital protuberance
What passes through the infraorbital foramina?
Infraorbital nerve and vessels.
What is the foramen magnum?
A large opening in the occipital bone that allows passage of the spinal cord from the brainstem.
What is the supraorbital notch or foramen?
An opening in the frontal bone above the eye socket for nerves and vessels.
What bones meet at the pterion?
The frontal, parietal, sphenoid, and temporal bones meet at the pterion.
What bones meet at the asterion?
The parietal, mastoid, and occipital bones meet at the asterion.
What does the posterior cranial fossa hold?
The cerebellum.
What are the four parts that form the Norma Lateralis?
Body, Lesser wing, Greater wing, Pterygoid processes (medial and lateral pterygoid plates).
What anatomical feature does the arcuate eminence mark?
The roof of the superior semicircular canal of the inner ear.
What is the function of the transverse groove in the posterior cranial fossa?
It serves as a groove for the transverse sinus.
What does the jugular foramen transmit?
The sigmoid sinus, which continues as the internal jugular vein, and the Glossopharyngeal (9), Vagus (10), and Accessory (11) nerves.
What is the function of the zygomatic process of the maxilla?
It articulates with the zygomatic bone.
What is the external occipital crest?
A ridge located on the external surface of the occipital bone that extends downward from the external occipital protuberance.
What is the external occipital protuberance (Inion)?
A prominent midline projection on the external surface of the occipital bone.
Which bones form the inferior row of the Norma Lateralis?
Nasal, maxilla, zygomatic, greater wing of sphenoid, and temporal.
What is the pterion and where is it located?
The pterion is the H-shaped formation of sutures on the side of the skull where four bones meet: frontal, parietal, sphenoid, and temporal bones. It is the ossified anterolateral fontanelle at the age of 3 months.
What is the anterior boundary of the infratemporal fossa?
Maxilla.
What are the components of the Pterygoid processes?
Medial pterygoid plate and Lateral pterygoid plate.
Which part of the Norma Lateralis is labeled as the 'Greater wing' in the image?
The yellow-colored section.
What structure is labeled as the 'Frontal crest'?
It is a bony ridge located on the internal surface of the frontal bone.
What is the orbital plate of the maxilla?
It forms the floor of the orbit.
Which bones form the superior row of the Norma Lateralis?
Frontal, parietal, occipital.
What divides the Norma Lateralis into temporal and infratemporal regions?
The zygomatic arch.
What is the significance of the supramastoid crest (inferior temporal line)?
The supramastoid crest, also known as the inferior temporal line, is a ridge on the temporal bone that serves as an attachment point for the temporalis muscle.
What is the petrous part of the temporal bone?
The petrous part of the temporal bone is a pyramid-shaped, dense region that houses the structures of the inner ear.
What is the glabella?
The smooth area between the eyebrows.
Which part of the temporal bone is visible in the Norma Occipitalis?
The mastoid part.
What is the maxillary process of the frontal bone?
A projection of the frontal bone that articulates with the maxilla.
What is the zygomatic process of the frontal bone?
A projection of the frontal bone that articulates with the zygomatic bone.
What are the wings of the sphenoid bone called?
The wings of the sphenoid bone are called the greater wing and the lesser wing.
Which part of the brain is held by the middle cranial fossa?
The temporal lobe of the brain.
What is the hypophyseal fossa, and what does it contain?
The hypophyseal fossa, also known as the sella turcica, is a saddle-shaped depression that contains the pituitary gland.
Which structures occupy the posterior cranial fossa?
Cerebellum, pons, and medulla.
What is the function of the Viscerocranium?
To form the facial skeleton.
What are the anatomical landmarks that bound the temporal fossa?
The temporal fossa is bounded anteriorly by the frontal process of the zygomatic bone and the zygomatic process of the frontal bone, superiorly and posteriorly by the temporal lines, and inferiorly by the zygomatic arch.
What is located below the zygomatic arch in the Norma Lateralis?
The infratemporal region.
What is the asterion and where is it located?
The asterion is the junction on the side of the posteroinferior skull where three bones meet: parietal, mastoid, and occipital bones. It is the ossified posterolateral fontanelle at the age of 1 year.
What is the styloid process?
Slender and elongated bony projections of the temporal bone that give attachment to muscles.
What is the function of the mastoid process?
It gives attachment to muscles and contains air cells.
Where is the external auditory meatus located?
Below the posterior part of the zygomatic process of the temporal bone.
What is the Bregma and when does the anterior fontanelle close?
The Bregma is the anterior fontanelle, and it closes at around 1.5 years.
What does the trigeminal impression house?
The sensory ganglia of the trigeminal nerve.
Which line on the mandible gives origin to the buccinator muscle opposite the last 3 molar teeth?
Oblique line
What are the main parts of the sphenoid bone?
The main parts of the sphenoid bone are the body, greater wing, and lesser wing.
What is the styloid process of the temporal bone?
The styloid process is a slender, pointed piece of bone just below the ear, serving as an anchor point for muscles associated with the tongue and larynx.
What is the Asterion and when does the posterolateral fontanelle close?
The Asterion is the posterolateral fontanelle, and it closes at the end of the first year.
Which part of the Norma Lateralis includes the Medial and Lateral pterygoid plates?
The Pterygoid processes.
What are the names of the two wings of the Norma Lateralis?
Lesser wing and Greater wing.
What part of the temporal bone houses the middle and inner ear?
The petrous part of the temporal bone.
What passes through the supraorbital notch or foramen?
Supraorbital nerve and vessels.
What is the supra-meatal triangle (Mac Ewen) and where is it located?
It lies postero-superior to the external auditory meatus and is used to locate the mastoid antrum.
Where is the trigeminal impression located on the temporal bone?
On the anterior surface of the petrous part of the temporal bone.
What are the two main parts the skull is divided into?
Neurocranium and Viscerocranium.
What marks the transition from the medulla to the spinal cord in the posterior cranial fossa?
Foramen magnum
What does the foramen rotundum allow passage of?
The maxillary nerve of the trigeminal nerve.
What does the foramen ovale allow passage of?
The mandibular nerve of the trigeminal nerve.
What is the medial boundary of the infratemporal fossa?
Lateral Pterygoid Plate.
Where is the mastoid process located?
Posterior to the ear, containing air cells and giving attachment to muscles.
What is the tympanic part of the temporal bone?
The tympanic part of the temporal bone surrounds the external acoustic meatus and forms part of the ear canal.
What is the function of the Pterygoid Hamulus?
The Pterygoid Hamulus acts as a pulley for the tendon of the tensor veli palatini muscle.
Which bones form the anterior cranial fossa?
What is the Crista galli?
A vertical projection of the ethmoid bone that serves as an attachment point for the falx cerebri.
What is the orbital plate of the frontal bone?
It is the portion of the frontal bone that forms the roof of the orbit and part of the anterior cranial fossa.
What passes through the foramen lacerum?
Nothing is transmitted vertically, but the internal carotid artery passes through it transversely.
What is the Pterion and when does the anterolateral fontanelle close?
The Pterion is the anterolateral fontanelle, and it closes at around 3 months.
What are the three parts into which the norma basalis interna is divided?
Anterior cranial fossa, Middle cranial fossa, Posterior cranial fossa.
What bone feature separates the anterior cranial fossa from the middle cranial fossa?
The lesser wing of the sphenoid.
Where is the groove for the transverse sinus located?
In the posterior cranial fossa.
Where is the internal acoustic meatus located relative to the jugular foramen?
Just superior to the jugular foramen.
What is the clinical significance of fontanelles being present at birth?
Fontanelles are present at birth to allow the overlap of skull bones during delivery.
What condition is associated with the delayed closure of fontanelles?
Delayed closure of fontanelles occurs in rickets.
Which part of the sphenoid bone contributes to the formation of the middle cranial fossa?
Greater wing of the sphenoid.
Which cranial fossa is located at the lowest level in the skull base?
The posterior cranial fossa.
What cranial nerves pass through the superior orbital fissure?
Cranial nerves 3 (oculomotor), 4 (trochlear), ophthalmic division of 5 (trigeminal), and 6 (abducens).
What does an elevated fontanelle indicate?
An elevated fontanelle indicates increased intracranial tension.
What bone feature separates the middle cranial fossa from the posterior cranial fossa?
The upper border of the petrous bone.
What forms the clivus?
The body of the sphenoid and the basilar part of the occipital bone.
Where is the foramen caecum located?
It is located at the base of the frontal crest.
What is the anterior clinoid process?
A projection of the lesser wing of the sphenoid bone that serves as an attachment site for the tentorium cerebelli.
Which cranial nerve passes through the Optic Canal?
Cranial Nerve II (Optic Nerve).
What is located between the coronoid and condyloid processes?
The mandibular notch.
What surrounds the hypophyseal fossa?
Four clinoid processes.
Which part of the temporal bone is labeled in the image?
Squamous part of the temporal bone.
What passes through the optic canal?
The optic nerve and the ophthalmic artery.
What is the significance of the lesser wing of the sphenoid bone?
It forms part of the floor of the anterior cranial fossa and contains the optic canal.
What is the Calvaria?
The topmost part of the neurocranium, which protects the cranial cavity that houses the brain.
What is the shape of the groove for the sigmoid sinus in the posterior cranial fossa?
S-shaped
What is the triangular eminence on the mandible known as?
Mental protuberance (mental tubercle)
What does the mental foramen transmit?
Mental nerve and vessels
What are the main features labeled in the image of the cranial fossae?
Internal acoustic meatus, hypoglossal canal, jugular foramen, groove for transverse sinus, cerebellar fossa, and cerebral fossa.
What is the largest bone in the human skull?
The mandible.
Where is the arcuate eminence located?
Near the center of the anterior surface of the petrous part of the temporal bone.
What marks the anterior portion of the occipital bone in the posterior cranial fossa?
Clivus
What is the diploë?
The intervening cancellous tissue between two layers of compact bones in the skull.
What are the primary functions of the mandible?
It holds the lower teeth in place, assists in mastication, and forms the lower jawline.
What does Norma Occipitalis refer to?
The view of the skull from the back.
What is the function of the Neurocranium?
To form a protective case around the brain (cranial skeleton).
What anatomical feature is located below the 2nd premolar teeth?
Mental foramen
What is transmitted through the foramen spinosum?
The middle meningeal artery.
What does Norma Frontalis refer to?
The view of the skull from the front.
What is the faint median ridge indicating the fusion of the two halves of the mandible called?
Symphysis menti
What does Norma Lateralis refer to?
The view of the skull from the side.
What does the hypoglossal canal transmit?
The hypoglossal nerve.
What is the function of the mylohyoid line on the mandible?
It gives attachment to the mylohyoid muscle and its posterior end gives attachment to the pterygomandibular ligament.
What is the sublingual fossa and where is it located?
It is located above the mylohyoid line and lodges the sublingual gland.
Which structures are transmitted through the internal acoustic meatus?
Facial nerve (VII), Vestibulocochlear nerve (VIII), and labyrinthine artery.
Where is the hypoglossal canal located relative to the foramen magnum?
Superior to the margin of the foramen magnum.
What does Norma Verticalis refer to?
The view of the skull from above.
What are the two main parts of the mandible?
The body and the ramus.
Which cranial nerve passes through the Foramen Rotundum?
Cranial Nerve V2 (Maxillary branch of Trigeminal Nerve).
Where is the submandibular fossa located on the mandible?
Below the mylohyoid line. It lodges the submandibular gland.
What is the function of the alveolar border in the mandible?
The alveolar border holds the lower teeth in place.
Which cranial nerve passes through the Cribriform plate?
Cranial Nerve I (Olfactory Nerve).
Where is the mandibular foramen located?
On the medial surface of the ramus.
What are the superior and inferior genial tubercles (mental spines) used for?
They provide attachment for muscles.
Which cranial nerve passes through the Hypoglossal Canal?
Cranial Nerve XII (Hypoglossal Nerve).
What does Norma Basalis (Interna & Externa) refer to?
The view of the skull from the base, both internal and external.
Which cranial nerves pass through the Superior Orbital Fissure?
Cranial Nerves III (Oculomotor), IV (Trochlear), V1 (Ophthalmic branch of Trigeminal), and VI (Abducens).
What features are shown on the medial surface of the ramus?
Lingula, mandibular foramen, and mylohyoid groove.
What is the significance of the mandibular notch?
It is the upper border between the coronoid and condyloid processes.
What are the two main parts of the mandible illustrated in the image?
Body and Ramus.
Where is the mandible located in relation to the maxilla?
The mandible is located inferior to the maxilla.
What are the key elements to identify in the different Norma views of the skull?
Names of the bones, names of the sutures, and features.
Which cranial nerve passes through the Foramen Ovale?
The Mandibular Nerve (V3 branch of the Trigeminal Nerve).
What is the significance of the inferior border (digastric fossa) in the mandible?
The inferior border (digastric fossa) serves as an attachment point for muscles involved in mastication and movement of the jaw.
Which cranial nerves pass through the Internal Acoustic Meatus?
Cranial Nerves VII (Facial) and VIII (Vestibulocochlear).
Which cranial nerves pass through the Jugular Foramen?
Cranial Nerves IX (Glossopharyngeal), X (Vagus), and XI (Accessory).
What is the lingula in the context of the mandible?
A bony projection on the medial surface of the ramus.
What is the mylohyoid groove?
A groove on the medial surface of the ramus that houses the mylohyoid nerve.
