LO 2 Flashcards
(105 cards)
1
Q
Where does the line of separation between the cranial and facial bones run?
A
From the supraorbital ridge of the frontal bone to the mastoid process of the temporal bone
2
Q
________ and ________ on the bony surface are landmarks for the attachments of associated muscles, tendons, and ligaments.
A
- Prominences
- Depressions
3
Q
________ are landmarks where various nerves and blood vessels enter or exit.
A
Openings in the bone
4
Q
The longitudinal suture running from the frontal bone to the occipital bone is called the _________
A
Saggital suture
5
Q
The suture that connects the occipital bone to the parietal bones is called the _______
A
Lamboidal suture
6
Q
The suture that connects the frontal bone to the parietal bones is called the ________
A
Coronal suture
7
Q
Define a process
A
- General term for any prominence on a bony surface
- E.g. Alveolar process; Coronoid process
8
Q
Define condoyle
A
- Specific type of prominence on bony surfaces - relatively large, convex prominences; usually involved in joints
- E.g. occipital condyle; Mandibular condyle
(aka condylar process)
9
Q
Define head (relating to bony projections)
A
- Rounded surface projecting from a bone by a neck
- E.g. Head of the condyle of the mandible – Includes the articulating surface of the condyle
10
Q
Define tuberosity
A
- Bony protuberance or bulge, often rough
- Typically attachment areas for muscles or tendons
- E.g. Maxillary tuberosity - Often described as a bulge distal to the maxillary 3rd
molar
11
Q
Define arch
A
- Shaped like a bridge with a bow-like outline
- E.g. Zygomatic arch (aka cheek bone) - formed by the union of processes from the temporal and zygomatic bones;
12
Q
Define cornu
A
- Horn-like prominence
- E.g. Greater cornu and lesser cornu of the hyoid bone
13
Q
Define tubercle/eminence
A
- Rounded elevation/projection on a bony surface
- E.g. genial tubercles (lingual foramen is in the middle of the genial tubercles)
- E.g. frontal eminence (forehead)
14
Q
Define crest
A
- A prominent, often roughened border or ridge
- E.g. Infratemporal crest; Alveolar crest
15
Q
Define line (relating to bony projections)
A
- Small, straight ridge
- E.g. superior temporal line; inferior temporal line
16
Q
Define spine (relating to bony projections)
A
- An abrupt prominence of bone that may be a blunt or sharply pointed projection
- E.g. spine of the sphenoid bone; anterior nasal spine
17
Q
Define notch
A
- An indentation at the edge of the bone
- E.g. mandibular notch; coronoid notch
18
Q
Define sulcus
A
- A shallow depression or groove that usually marks the course of an artery or nerve
- E.g. infraorbital sulcus - the groove in the floor of the orbital surface
19
Q
Define fossa
A
- Deeper depression on a bony surface
- Fossae can be portions of joints, attachment areas for muscles, or have other functions
- E.g. temporal fossa
20
Q
Define bony plate
A
- Areas of the bones that are not prominences or depressions
- Can also be demarcated
- Flat, bony structures
21
Q
Define foramen/foramina
A
- A short, window-like opening in the bone
- E.g. Mental foramen; Mandibular foramen
22
Q
Define canal (relating to bony openings)
A
- Longer, narrow tube-like opening in the bone
- E.g. mandibular canal
23
Q
Define meatus
A
- A type of canal
- E.g. external acoustic meatus
24
Q
Define a fissure (relating to bony openings)
A
- A narrow, cleft-like opening in a bone
- E.g. superior orbital fissure; inferior orbital fissure
25
Define ostium/ostia
1. A small opening, especially as an entrance into a hollow organ or canal
2. A sinus ostium is the opening that connects a sinus to the nasal cavity.
3. Ostia may be blocked by inflammation of soft tissue (edema) or by bone (ossification of the ostium).
4. A blocked sinus ostium will cause an accumulation of fluid /exudate
5. E.g. maxillary sinus ostia
26
Define aperture
1. An opening or orifice in bone
2. E.g. Piriform aperture
27
Define articulation
1. An articulation is an area of the skeleton where the bones are joined to each other
2. An articulation of the bones can be either a movable or an immovable type of joint
3. E.g. Temporomandibular joint (TMJ) - Mandible articulates with the temporal bone
28
Define suture
1. A suture is the union of bones joined by fibrous tissue
2. Sutures appear on the dry skull as jagged lines - generally considered immovable
3. E.g. coronal suture, sagittal suture, lambdoidal suture
29
List the types of bony prominences
1. Process
2. Condoyle
3. Head
4. Tuberosity
5. Arch
6. Cornu
7. Tubercle/eminence
8. Crest
9. Line
10. Spine
30
List the types of bony depressions
1. Notch
2. Sulcus/Sulci
3. Fossa
31
List the types of bony openings
1. Foramen(pl. Foramina)
2. Canal
3. Meatus
4. Fissure
5. Ostium (pl. Ostia)
6. Aperture
32
What are the 8 cranial bones?
1. Occipital (1)
2. Frontal (1)
3. Sphenoid (1)
4. Ethmoid (1)
5. Parietal (2)
6. Temporal (2)
33
What are the 14 facial bones?
1. Mandible = 1
2. Maxillae = 2 (Paired)
3. Nasal bones = 2 (Paired)
4. Vomer = 1
5. Zygomatic = 2 (Paired)
6. Lacrimal = 2 (Paired)
7. Inferior nasal conchae = 2 (Paired)
8. Palatine = 2 (Paired)
34
Describe the occipital bone
1. Single cranial bone
2. Forms the posterior part of the skull and the base of the cranium
3. Articulates with the parietal, temporal, and sphenoid bones of the skull and the first cervical vertebra
35
The foramen magnum is completely formed by the _________
Occipital bone
36
Lateral and anterior to the foramen magnum are the paired __________, curved and smooth projections
Occipital condyles
37
The occipital condyles have a movable articulation with the __________ (i.e., the first cervical vertebra of the vertebral column)
Atlas
38
__________ is a four-sided bony projection found anterior to the foramen magnum
Pharyngeal tubercle
39
What is the hypoglossal canal?
1. A paired bony passage which is situated above the Occipital Condyle (OC) and transmits hypoglossal nerve and blood vessels.
40
What is the jugular notch?
A large, visible dip in between the neck in humans, between the clavicles, and above the manubrium of the sternum
41
What is the jugular foramen?
A cavity formed by the petrous part of the temporal bone anteriorly and the occipital bone posteriorly.
42
Describe the frontal bone
1. Single cranial bone
2. Forms the anterior part of the skull superior to the eyes in the frontal region
3. Includes the forehead, the roof of the orbits, and part of the nasal cavity
4. Articulates with the parietal bones, sphenoid bone, lacrimal bones, nasal bones, ethmoid bone, zygomatic bones, and maxillae
43
The orbital plate of the frontal bone forms the __________ or __________.
1. Superior wall
2. Orbital roof
44
The curved elevations of the frontal bone over the superior part of the orbit are the __________, subjacent to the eyebrows.
Supraorbital ridges
45
The supraorbital notch is located on the medial part of the __________ and is where the _________ and _________ travel from the orbit to the forehead
1. Supraorbital ridge
2. Supraorbital artery
3. Nerve
46
Describe the frontal sinuses
1. Internally, the paired frontal sinuses are located in the frontal bone just superior to the nasal cavity
2. Left and right frontal sinuses are separated by a septum
3. Each frontal sinus communicates with and drains into the nasal cavity
47
From the inferior view of the frontal bone, each _________ is visible (located just inside the lateral part of the supraorbital ridge) and contain the __________
1. Lacrimal fossa
2. Lacrimal glands (which produce
lacrimal fluid)
48
Describe the parietal bones
1. Paired cranial bones
– located posterior to the frontal bone, forming the greater part of the right and left lateral walls and the roof of the skull – articulate with each other at the sagittal suture
2. Articulate with the occipital, frontal, temporal, and sphenoid bones
3. Articulate with the occipital bone at the lambdoidal sutures
49
Describe the temporal bones
1. Paired cranial bones
2. Form the lateral walls of the skull
in the temporal region and part of
the base of the skull in the
auricular region.
3. Each articulates with one zygomatic and one parietal
bone, the occipital and sphenoid bones, and the mandible.
4. **Each temporal bone is composed of four parts: the squamous, tympanic, petrous, and mastoid process**
50
Describe the squamous part of the temporal bone
1. Forms the braincase and the the zygomatic process of the temporal bone which forms a part of the zygomatic arch
(the cranial part of the TMJ)
2. On the inferior surface of the
zygomatic process of the temporal bone is the articular fossa - anterior to the articular
fossa is the articular eminence
51
Describe the tympanic part of the temporal bones
The tympanic part of the temporal bone forms most of the external acoustic meatus (EAM), a short canal leading to the tympanic cavity, located posterior to the articular fossa.
52
Describe the petrous part of the temporal bone
1. On the inferior aspect of the petrous part of the temporal bone and posterior to the external acoustic meatus is a large roughened projection, the mastoid process.
2. Medial to the mastoid process is the mastoid notch
3. Inferior and medial to the external acoustic meatus is a long, pointed bony projection, the styloid process.
4. The jugular notch of the temporal bone is visible
5. On the intracranial surface of the petrous part of the temporal bone is the internal acoustic meatus (IAM), which carries the facial cranial nerve (VII) and the VIII cranial nerve Vestibulocochlear nerve).
53
Describe the sphenoid bone
1. Single bone
2. Midline bone since it runs through the midsaggital section - internally wedged between several other bones in the anterior part of the cranium
3. The sphenoid is important to dental professionals since it is the site for attachment for most of the muscles of mastication, as well as providing passage by way of foramina for the branches of the trigeminal nerve (5th cranial nerve that serves the oral cavity).
54
Describe the articulations of the sphenoid bones
1. Articulates with the frontal, parietal, ethmoid, temporal, zygomatic, maxillae, palatine, vomer, and occipital bones
2. Helps to connect the cranial and facial skeletons
55
Describe the sphenoid sinuses
1. In the middle part is the body of the sphenoid bone – contains the sphenoidal sinuses
2. The sphenoid sinuses communicate with and drain into the nasal cavity through an opening superior to each superior nasal
concha.
3. The sphenoidal sinuses cannot be
palpated during an extraoral examination
56
What is the clinical significance of the sinuses?
1. Infection in the paranasal sinuses can
cause earaches, neck pain, and deep
aching at the back of the head, although
the sphenoidal sinuses are less
frequently affected.
2. The drainage of mucus down the posterior wall of the pharynx (postnasal drip) can cause pharyngitis
(sore throat).
57
What are the 3 paired processes projecting from the sphenoid bone?
1. The anterior process is the
lesser wing.
2. The postero-lateral process
is the greater wing.
3. 3. Inferior to the greater wing of the sphenoid bone is the pterygoid process.
58
Describe the pterygoid process
1. Consists of two plates - flattened lateral pterygoid plate; thinner medial pterygoid plate (with the pterygoid fossa between them)
2. The pterygoid process is an area of attachment for some of the muscles of mastication.
59
The _________, a thin curved process, is the inferior termination of the medial pterygoid plate (a “hook-like” projection).
(pterygoid) hamulus
60
The _________ is between the
pterygoid process and the maxillary tuberosity
Pterygopalatine fossa
61
Describe the foramina of the sphenoid bone
1. Many foramina and fissures are located in the sphenoid bone
2. The superior orbital fissure (with ophthalmic nerve)
3. Foramen rotundum (with maxillary nerve)
4. Foramen foramen ovale (with mandibular mandibular nerve).
5. These foramina, fissures are located in the sphenoid, which carry nerves and blood vessels of the head and neck and are significant to dental professionals.
62
Decribe the relationship between the sphenoid bone and orbit
1. The orbital surface of the greater wing creates the posterior part of the lateral wall of the orbit
2. The lesser wing forms the base of the orbital apex, the deepest part of the orbit
3. Frontal view - The round opening in the orbital apex is the optic canal, which lies between the two roots of the lesser wing
4. The second cranial or **optic nerve** passes through the optic canal to reach the eyeball
5. The **ophthalmic artery** also extends through the canal to reach the eye.
63
Describe the ethmoid bone
1. a single midline cranial bone of the skull that runs through the midsagittal plane similarly to the sphenoid bone
2. an irregularly shaped, spongy bone that provides the floor of the front part of the skull and the roof of the nasal cavity
3. consists of two masses of thin plates enclosing air cells and looks like a sieve
4. helps connect the cranial skeleton to the facial skeleton similarly to the sphenoid bone.
5. If the sphenoid is the most difficult cranial bone to describe and visualize, the ethmoid bone is the second most difficult. - It has a number of features and projections, but unlike the sphenoid the ethmoid cannot be seen from various views of the skull.
64
What does the ethmoid bone articulate with?
The ethmoid bone articulates with the frontal sphenoid, lacrimal, and maxilla and adjoins the vomer at its inferior and posterior borders.
65
What 2 unpaired plates form the ethmoid bone?
1. The midline vertical perpendicular plate and the horizontal cribriform plate (which it crosses)
2. A vertical midline continuation of
the perpendicular plate superiorly into the cranial cavity is the wedge-shaped crista galli
3. The crista galli serves as an attachment for layers covering the brain
4. The perpendicular plate is easily seen in the nasal cavity and aids the nasal septal cartilage and vomer in forming the nasal septum
66
The lateral parts of the ethmoid bone form the ___________ and the _________ in the nasal cavity, and the paired orbital plates
1. Superior nasal conchae
2. middle nasal conchae
67
The _________, visible from the inside of the cranial cavity and present on the superior aspect of the bone and surrounding the cristal galli, is perforated by foramina to allow the passage of olfactory nerves for the sense of smell.
1. cribriform plate
2. olfactory nerves
68
The orbital plate of the ethmoid bone forms the _________.
medial orbital wall
69
Between the orbital plate and the conchae are the _________ or _________, which are a variable number of small cavities in the lateral mass of the ethmoid.
1. ethmoidal sinuses
2. ethmoid air cells
70
_________ form most of the wall between the nasal cavity and the orbits
Lateral masses
71
_________ forms the superior portion of the nasal septum
Perpendicular plate
72
__________ forms the roof of the nasal cavity
Cribiform plate
73
___________ is small holes within the : small holes within the cribriform plate for the passage od the first cranial nerve (for smell)
Olfactory foramina
74
__________ is an upward extension of bone above the cribriform plate, acts as an anchoring point for one of the coverings of the brain
Crista Galli
75
__________ are two scroll-shaped projections with a mucus membrane on either side of the nasal septum. Function to cause air turbulence and trap inhaled particles
Nasal concha (turbinates)
76
Describe the maxilla
1. The maxilla is very complex, with portions in almost every significant area of the skull.
2. It has a number of features and projections, which allows it to be seen from various views of the skull (It is very difficult to describe and visualize.)
3. The upper jaw or maxilla consists of
two maxillary bones, or maxillae,
that are fused together at the
intermaxilary suture.
4. It helps structure part of the eye socket, or orbit, as well as the structure of the hard palate and nasal cavity.
5. Contains roots of maxillary teeth
77
What does the maxilla articulate with?
The maxillae articulate with the following bones of the cranium and face: – frontal, lacrimal, nasal, inferior nasal concha, vomer, sphenoid, ethmoid, palatine, and zygomatic bones.
78
What surfaces does the body of the maxilla contain?
1. The body of the maxilla has orbital,
nasal, infratemporal, and facial surfaces.
2. Each body of the maxilla is somewhat pyramidal.
79
Describe the maxillary sinuses
Each of the bodies of the maxillae contain air-filled spaces called paranasal sinuses, or
the maxillary sinuses.
80
Describe the relationship between the maxillary sinus and the alveolar process
1. Due to the close proximity of the maxillary sinus to the alveolar process containing the roots of the maxillary posterior teeth, the periodontal tissues of the teeth may be in direct contact with the mucosa of the maxillary sinus
2. This close proximity can cause serious clinical problems, such as
secondary sinusitis and perforation during infection, extraction, or trauma
related to the maxillary posterior teeth.
3. The discomfort associated with a primary maxillary sinus infection can
mimic the discomfort of an endodontic or periodontal infection of the
maxillary posterior teeth.
4. With age, the enlarging maxillary sinus may surround the roots of the
maxillary posterior teeth.
5. If the maxillary posterior teeth are lost, the maxillary sinus may expand even more, thinning the bony floor of the alveolar process so that only a thin shell of bone is present.
81
Describe maxillary sinusitis
1. Secondary sinusitis of dental origin occurs mainly in the maxillary sinuses, since the maxillary posterior teeth and associated tissues are in close proximity to these sinuses. Thus, maxillary sinusitis can result from the spread of infection from a periapical abscess initiated by a maxillary posterior tooth that perforates the sinus floor to involve the sinus mucosa. In addition, a contaminated tooth or root fragments can be displaced into the maxillary sinus during an extraction, creating an infection.
2. However, most infections of the maxillary sinuses are not of dental origin, but are caused by an upper respiratory infection—an infection in the nasal region that spreads to the sinuses. An infection in one sinus can travel through the nasal cavity to other sinuses and lead to serious complications for the patient, such as infection of the cranial cavity and brain. Thus, it is important that any sinusitis be treated aggressively by the client’s physician to eliminate the initial infection.
82
Describe the maxillary tuberosity
1. On the posterior portion of the body of the maxilla is a rounded, roughened elevation—the maxillary tuberosity—just posterior to the most distal molar of the maxillary dentition.
2. The maxillary tuberosity is a landmark for the administration of the posterior superior alveolar local anesthetic block.
83
The zygomatic process of the maxilla articulates with the ____________.
zygomatic bone
84
Describe the alveolar process of the maxilla
1. The alveolar process of the maxilla projects downwards from the body of the maxilla.
2. It is the thickest and most spongy part of the maxillary bone.
3. It is broader behind than in front to accommodate the molar teeth, and it is excavated by deep cavities or bony sockets for the reception of the maxillary teeth.
85
When the maxillae are articulated with each other, their alveolar processes together form the ___________
alveolar arch
86
Describe the sockets of the alveolar process of the maxilla
1. There are generally 8 sockets– vary in size and depth according to the teeth they contain
2. Sockets for the incisors are single, but deep and narrow.
3. Sockets for the canine tooth is the deepest
4. Sockets for the molars are the widest, and are subdivided into minor cavities by septa
87
Describe the facial ridge/canine eminence
The facial ridge over the maxillary canine—the canine eminence—is especially prominent and is a landmark for the administration of the anterior superior alveolar local anesthetic block.
88
Describe the facial maxillary bone
1. The maxillary bone over the facial surface of the maxillary teeth is less dense than the mandible is over similar teeth.
2. This allows a greater incidence of clinically adequate local anesthesia for the maxillary teeth when the agent is administered as a local infiltration.
89
Describe the palatine processes of the maxilla
1. The palatine process of the maxilla is thick and strong, and horizontally projects medial ward from the nasal surface of the bone.
2. It forms a considerable part of the floor of the nose and the roof of the mouth, and is much thicker in front than behind.
3. Its inferior surface is concave, rough, and uneven, and forms, with the palatine process of the opposite bone, the anterior 3⁄4 of the hard plate.
4. When the two maxillæ are articulated, a funnel-shaped opening—the incisive foramen—is seen in the middle line,immediately behind the maxillary incisor teeth.
90
Describe the incisive foramen
1. The incisive foramen is a landmark for the administration of the nasopalatine local anesthetic block.
2. The soft tissue bulge over the incisive foramen is called the incisive papilla.
91
Describe the infraorbital foramen
1. The infraorbital sulcus becomes the infraorbital canal and then terminates on the facial surface of the maxilla as the infraorbital foramen.
2. It is located approximately 2 cm
inferior to the midpoint of the lower
margin of the orbit, in a vertical line
with the supraorbital notch, which is
superior to it.
3. This foramen transmits
the infraorbital nerve and blood
vessels.
4. The infraorbital foramen is a landmark for the administration of the infraorbital local anesthetic block.
92
Describe canine fossa
1. Inferior to the infraorbital foramen is an elongated depression- the canine fossa.
2. The canine fossa is just postero-superior to the roots of the maxillary canine teeth.
93
What are the functions of the palatine bones
1. Form the posterior portion of the hard palate
2. Contribute to the floors of the orbits
94
What do the palatine bones articulate with
1. With other palatine bone
2. Maxillae
3. Sphenoid
4. Ethmoid
5. Inferior nasal conchae
6. Vomer
95
Describe the zygomatic bones
1. Contribute to the rim and lateral wall of the orbit
2. Form part of the zygomatic arch
96
Describe the lacrimal bones
1. Smallest and most fragile bone of the face
2. Situated at the front part of the medial aspect of the orbit.
3. Contains - the lacrimal sac; the naso-lacrimal duct
97
Describe the functions of the nasal bones
1. Support the bridge of the nose
2. Connect to cartilages of the distal part of the nose (external nares)
98
What do the nasal bones articulate with?
1. With other nasal bones
2. Ethmoid
3. Frontal bones
4. Maxillae
99
Describe the vomer bone
1. One of the unpaired facial bones of the skull.
2. Located in the midsagittal line
100
What does the vomer articulate with?
1. sphenoid
2. ethmoid
3. palatine bones
4. maxillae
101
Describe the inferior nasal conchae
1. Extends horizontally along the lateral wall of the nasal cavity
2. Consists of a lamina of spongy bone, curled upon itself like a scroll.
102
Describe the mandible
1. Single fused facial bone
2. Forms the lower jaw
3. The only freely movable bone of the skull
4. Largest and strongest facial bone
103
The ___________ is the bony prominence of the chin, located deep to the roots of the mandibular incisors.
mental protuberance
104
Inferior to the apices of the mandibular first and second premolars, is an opening, the ___________.
mental foramen
105
Describe the hyoid bone
1. (Neither a Cranial Bone, nor a Facial Bone)
2. The only free-floating bone in the body
3. Functions of the hyoid bone - Supports the larynx; Attaches muscles of the larynx, pharynx, and tongue
