Week 1 - head and neck (skull, dental, neck triangles) Flashcards
What are the characteristic features of cervical vertebrae?
Triangular vertebral foramen
Bifid spinous process
Transverse foramina
Between which bones does the nodding ‘yes’ movement occur?
Between atlas and the occiput
Between which bones does the shaking of the head ‘no’ movement occur?
Between atlas and axis
What are the articular surfaces of the atlanto-occipital joint?
occipital condyles and superior articular facets of atlas
Which movements occur at the atlanto-occipital joint?
Flexion, extension, a small amount of lateral flexion
Which movements occur at the atlanto-axial joint?
Axial rotation
Limited flexion, extension, lateral flexion
Which ligament wraps around the odontoid peg to enable axial rotation?
The transverse ligament of atlas
What are the unusual features of atlas?
No vertebral body, no spinous processes
What is the neurocranium?
The 8 bones that surround and protect the brain
What is the viscerocranium?
The 14 bones that make up the face
Which bones make up the neurocranium?
(mneumonic STEP OF) Frontal, sphenoid, ethmoid, occipital, temporal x2, parietal x2.
Which bones make up the viscerocranium?
Mandible, vomer, nasal bones x2, lacrimal bones x2, zygomatic bones x2, inferior nasal conchae x2, palatine bones x2, maxillae x2
Where is the lacrimal bone?
The infero-medial aspect of the orbit
The infra-orbital canal lies within which bone?
The maxilla - one canal each side of the nose
What travels in the infra-orbital canal?
The infraorbital nerve - a branch of the maxillary division of the trigeminal nerve
What travels through the mental canal?
The mental nerve, terminal branch of inferior alveolar nerve (from trigeminal), mental artery
Where is the mental canal?
In the mandible, one on each side, usually adjacent to the root of the mandibular second premolar tooth
Where is the squamous suture?
Between the parietal and temporal bones
Where is the coronal suture?
Between the frontal and parietal bones
Where is the lambdoid suture?
Between the parietal and occipital bone
Within which bone does the external acoustic meatus lie?
Temporal bone
Where is the mastoid process?
Inferior prominence of the temporal bone, just posterior to the ear
Where is the styloid process of the temporal bone?
inferomedial and anterior to the ear
Where is the incisive foramen of the maxilla?
centrally, anterior aspect of the roof of the mouth, just behind the two front teeth
What goes through the incisive foramen/ nasopalatine canal?
Greater palatine artery and vein, nasopalatine nerve (from maxillary)
What is the zygomatic arch?
The cheek bone, a thin arch of maxillary and temporal bone
What is the crista galli?
A thick midline, smooth triangular process from the superior surface of the ethmoid bone
What is the purpose of the crista galli?
To separate the olfactory bulbs, anterior attachment for the falx cerebri
What are the parts of the sphenoid bone?
Lesser wing, greater wing, sella turcica, medial and lateral pterygoid plate
Where is the vomer?
In the midline of the nasal cavity, forms the posterior-inferior part of the nasal septum
Which bones does the vomer articulate with?
Palatine, maxilla, ethmoid, sphenoid
What nerve goes through the cribriform plate?
The olfactory nerve (CNI)
What goes through the optic canal?
Optic nerve (CNII), ophthalmic artery, dural sheath of optic nerve
What goes through the Superior Orbital Fissure?
Oculomotor nerve (CNIII), Trochlear nerve (CNIV), Ophthalmic nerve (CNV1), Abducens nerve (CNVI), ophthalmic veins
What goes through the foramen rotundum?
Maxillary nerve (CNV2)
What goes through the foramen ovale?
Mandibular nerve (CNV3), acessory meningeal branch of maxillary artery, emissary vein (lesser petrosal nerve)
What nerves go through the internal acoustic meatus?
Facial nerve (CNVII), Vestibulocochlear nerve (CNVIII)
What goes through the Jugular foramen?
Glossopharyngeal nerve (CNIX), Vagus (CNX), descending portion of Accessory nerve (CNXI), internal jugular vein
What nerve goes through the hypoglossal canal?
Hypoglossal nerve (CNXII)
What goes through the foramen caecum?
Emissary veins
What goes through the foramen spinosum?
Middle meningeal artery
What goes through the foramen lacerum?
The Greater petrosal nerve - but it is mostly covered by connective tissue
What goes through the carotid canal?
Internal carotid artery
What goes through the foramen magnum?
Brainstem/spinal cord, vertebral arteries, ascending portion of spinal accessory nerve (CNXI)
What is the condylar process of the mandible?
The posterior superior aspect of the mandible, forms the TMJ
Where is the coronoid process of the mandible?
A bony projection on the anterosuperior aspect of the mandible
Where is the mandibular foramen?
On the medial surface of the ramus of the mandible - one on each side
Where are the mental foramen?
On the superficial surface of the body of the mandible, lateral to the midline - one on each side
Where is the mental protuberance?
On the superficial inferior aspect of the midline of the mandible
where is the mental tubercle?
One on each side, protrusions on the body of the mandible, either side of the mental protuberance
What are the four main parts of the mandible?
Ramus, Angle, Body, Aveolar part
What movements can occur at the temporomandibular joint?
Protrusion/retraction, lateral deviation, elevation and depression
Why is the TMJ considered an atypical joint?
Articular surfaces are lined with fibrocartilage rather than hyaline cartilage
What are the articular surfaces that make up the TMJ?
Temporal bone: mandibular fossa and articular tubercle
Mandible: condylar process
Which ligaments are involved in the TMJ?
Lateral temporomandibular ligament, (stylomandibular ligament, sphenomandibular liigament)
Which muscles elevate the jaw?
Temporalis, masseter, medial pterygoid muscles
Which muscles depress the jaw?
Lateral pterygoid, digastric, geniohyoid and mylohyoid muscles
Which muscles protrude the jaw?
Lateral pterygoid, medial pterygoid, masseter
Which muscles retract the jaw?
Posterior fibres of temporalis, deep part of masseter
Which muscles are involved in lateral deviation of the jaw?
Posterior fibres of temporalis, digastric, mylohyoid, geniohyoid (ipsilateral movement)
Lateral and medial pterygoids (contralateral movement)
What are the two divisions of the oral cavity?
Vestibule and oral cavity proper
What is the vestibule in the mouth?
The space between the teeth and the inner mucosal lining of the lips and cheeks
How many teeth do human adults have?
32
How many of each type of tooth is there?
8 incisors
4 canines
8 premolars
12 molars
What are the 9 surfaces of a tooth?
Incisal, occlusal, mesial, distal, buccal, palatal, lingual, labial, cervical
What is the incisal surface of a tooth?
The biting edge of the incisors and canines
What is the occlusal surface of a tooth?
The biting surface of premolars and molars
What is the mesial surface of a tooth?
The surface of any tooth nearest the mid-line of the arch
What is the distal surface of a tooth?
The surface of any tooth furthest from the midline of the arch
What is the buccal surface of a tooth?
The surface facing the cheeks (molars and premolars)
What is the palatal surface of a tooth?
The surface facing the palate of all upper teeth
What is the lingual surface of a tooth?
The surface facing the tongue in all lower teeth
What is the labial surface of a tooth?
The surface facing the lips (Incisors and canines)
What is the cervical surface of a tooth?
The part of the tooth next to the gingival margin
What are the layers of a tooth from superficial to deep?
Enamel, dentin, pulp chamber (blood vessels and nerves)
What is cementum?
The calcified substance covering the root of a tooth - a kind of continuation of the enamel layer
What are the functions of each type of tooth?
Incisor and canines: biting pieces of food
Premolar: tearing and grinding food
Molar: chewing and grinding food
What are the distinguishing features of incisors?
Chisel-shaped sharp edge, one root. distal occlusal surface more rounded than the mesial. Upper incisors are wider than lower incisors.
What are the distinguishing features of canines?
More pointed and slightly larger than incisors, one root. Upper canines are broad relative to their height, lower canines are narrow. The mesial occlusal ridge is usually shorter than the distal occlusal ridge.
What are the distinguishing features of premolars?
2 cusps, 1 or 2 roots. Upper: oval occlusal outline, two cusps of equal size. Lower: round occlusal outline, buccal cusp larger than lingual cusp. Long aspect of roots angle distally.
What are the distinguishing features of molars?
4 or 5 cusps, 2 roots (lower) 3 roots (upper). Upper: 3-4 major cusps and a rhombus-shaped outline. lower: 4-5 major cusps and a more square outline. all roots angle distally
What are the key features of deciduous teeth?
- Crowns with thinner enamel, whiter and more opaque
- More bulbous crowns
- thinner and shorter roots
- deciduous molars have divergent roots
- wider and more vascularised pulp chambers
What are the features of 3rd Molars?
Fused roots, less than 4 cusps, irregular shaped, smaller crowns