Week 3-4 Bones of the Head & Neck PDF

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Weeks 3-4 Bones of the Head and Neck

Bones of the Skull: divided up into two portions: Cranial = portion protecting the brain Facial = portion associated with the face

Bones of the Skull: 22 Bones Page 49,63 of textbook Cranial Frontal = 1 Parietal = 2 Temporal = 2 Occipital = 1 Sphenoid = 1 Ethmoid = 1

Total = 8 Cranial Bones

Facial Vomer = 1

Maxilla = 2 Palatine = 2 Zygomatic = 2 Lacrimal = 2 Nasal = 2 Inferior Nasal Conchae = 2

Mandibular = 1 Total = 14 Facial Bones

Nasal Septum = Perpendicular plate of Ethmoid + Triangular Vomer Bone

Frontal Bone  Forms forehead  Bony projection under eyebrow  Superior portion of eye Parietal Bone  Forms superior and lateral walls of cranium Temporal Bone  Lies inferior to parietal bones Occipital Bone  Most posterior bone of cranium  Forms floor and back wall of skull Sphenoid Bone  Forms part of floor of cranial cavity  Butterfly shaped bone that spans width of skull Ethmoid Bone BIO4324 Head and Neck Anatomy Weeks 3-4 Lecture NotesAcademic Year 2018-2019 1

   

Irregular shaped bone Forms “roof” of nasal cavity Separates nasal cavity from brain Lies anterior to sphenoid

Vomer Bone  Medial line of nasal cavity  Triangular shaped bone Maxilla  Forms upper “jaw”  Anterior area of hard palate Palatine Bone  Lie posterior the maxillae  Posterior part of hard palate Zygomatic Bone  “checkbones” Lacrimal Bone  Finger-sized bone  Forms part of medial wall of orbit (eye) Nasal Bone  Small rectangular bones forming bridge of nose Inferior Nasal Conchae  Thin curved bones projecting from lateral wall of nasal cavity Mandible  “lower jaw”

Important Sutures of the Skull: Between frontal & parietal bones = Coronal Suture Between parietal bones = Sagittal Suture Between occipital bone & parietal bones = Lambdoidal Suture Between temporal bone & parietal bones = Squamous Suture

Orbital Bones BIO4324 Head and Neck Anatomy Weeks 3-4 Lecture NotesAcademic Year 2018-2019 2

Area of Orbit

Skull Bones

Inferior Portion (floor)

Maxillary, Palatine, Zygomatic

Superior Portion (roof)

Frontal

Medial Wall

Lacrimal, Ethmoid, Maxillary

Lateral Wall

Zygomatic, Sphenoid

Posterior Wall

Sphenoid, Palatine

Landmarks of the Bones of the Skull Bone Markings  Special features of a bone designed to perform a special function Categories of bone markings: 1. Projections/processes = bone elevation 2. Depressions/cavities = indentations in bone Projection  Site of muscles/ligament attachment    

Spine: sharp, pointed projection Tuberosity or eminence: large, round projection (nob of bone) Crest: narrow ridge of bone or raised edge Line: narrow ridge of bone, less prominent than a crest

Depression  Allows blood vessels & nerves to pass  Fossa: Shallow depression  Fissure: Narrow slit-like opening  Foramen: Hole or opening through bone

Mandible Page 68-70 of textbook  Largest & strongest of all facial bone BIO4324 Head and Neck Anatomy Weeks 3-4 Lecture NotesAcademic Year 2018-2019 3

 Only free moveable bone in the skull

#4 body #3 mental foramen #7 ramus #1 mandibular foramen #6 angle #11 coronoid notch (concave forward curve) #10 mental protuberance or mentum. #5 external oblique line (outside diagonal line) #8 condyle #2 internal oblique line (inside diagonal line) #9 coronoid process #12 mandibular notch #13 mandibular symphysis o alveolar process = area of bone that contains teeth

Note:  Distal last mand. molar = retromolar triangle  Covered in a dense pad of tissue = retromolar pad Lingual View of Mandible

MAXILLA Page 62 in textbook

BIO4324 Head and Neck Anatomy Weeks 3-4 Lecture NotesAcademic Year 2018-2019 4

 “Upper jaw”  Consists of 2 bones that fuse together

Maxillary Processes: Alveolar process Frontal process

Zygomatic process Palatine process

Foramen: Infraorbital foramen Superior alveolar foramen

#7 Incisive foramen #3 Greater palatine foramen #1 Lesser palatine foramen

Sutures: #6 Medial Palatine Suture #5 Transverse Palatine Suture #2 Maxillary tuberosity Page 65 of text book  Facial ridge superior the max. canine = canine eminence  Elongated depression = canine fossa

Maxilla Articulates with - Name bones: BIO4324 Head and Neck Anatomy Weeks 3-4 Lecture NotesAcademic Year 2018-2019 5

 frontal  lacrimal  nasal  inferior nasal conchae  vomer  sphenoid  ethmoid  palatine  zygomatic

Zygomatic Bone  AKA cheekbone Articulates (meets) with - Name bones:  Frontal  Temporal  Sphenoid  Maxilla

Zygomatic bone

Temporal process

Frontal Process

Maxilla Process

Temporal Bone BIO4324 Head and Neck Anatomy Weeks 3-4 Lecture NotesAcademic Year 2018-2019 6

 Form inferior lateral wall of cranium  Surrounds ear area

#1 = Mastoid Process  Rough, enlarged projection on the temporal bone  Bump felt behind the ear.  Provides area of muscle attachment for muscles which move the head. #2 = Styloid Process  Long, sharp projection near opening of ear canal.  Point of attachment for muscles and ligaments #3 = Zygomatic Process  Forward projection of temporal bone towards zygomatic bone.  Area of muscle attachment #4 = Articular Eminence #5 = Articular Fossa #6 = Postglenoid Process Zygomatic Arch = Union:  temporal process of zygomatic bone  zygomatic process of temporal bone Zygomatic Arch = one cranial bone (temporal bone) + one facial bone (zygomatic bone)

Sphenoid Bone: BIO4324 Head and Neck Anatomy Weeks 3-4 Lecture NotesAcademic Year 2018-2019 7

 Bat shaped irregular bone It can be seen:  Undersurface of skull  Laterally near temporal area  In eye orbit  Unique function of joining with ALL other cranial bone  It can be thought of as the last piece of the puzzle which stabilizes bones of skull.

Label: Page 54 in textbook #7 Body

#8 Pterygoid Fossa- the dip in the bone

#1 Greater wing

#6 Hamulus

#2 Lesser Wing

#3 Superior Orbital Fissure

#4 Lateral Plate of Pterygoid Process #5 Medial Plate of the Pterygoid Process Occipital Bone 

Forms posterior wall and floor of skull

 foramen magnum = opening for spinal cord  occipital condyles = lateral elevations of foramen magnum  Occipital protuberance = elevation on outer surface Frontal Bone BIO4324 Head and Neck Anatomy Weeks 3-4 Lecture NotesAcademic Year 2018-2019 8

Supraorbital Ridge  superior orbit  Curved elevation Supraorbital notch  medial part of supraorbital ridge Hyloid Bone  Unique bone in that it DOES NOT articulate directly with another bone.  Suspended from the styloid process by 2 ligaments  Shape is complementary to the mandible  Purpose = forms a rigid place for muscles from tongue, larynx and other structures to attach Paranasal Sinuses  Air filled cavities within bone  paired  Lined with mucous membranes (secrete mucous)  Continuous with nasal cavities Purpose:  Lighten the skull bones  Acts as sound resonators  Provide mucous for the nasal cavity Paranasal Sinuses: Name Frontal sinuses Sphenoid Sinuses Ethmoid Sinuses Maxillary Sinuses largest sinuse

Location Frontal bone Sphenoid bone Ethmoid bone Maxillary bone

REVIEW QUESTIONS: The foramen magnum is part of the ____________________________ bone. BIO4324 Head and Neck Anatomy Weeks 3-4 Lecture NotesAcademic Year 2018-2019 9

The forehead bone is the _____________________________________ bone. The lower jaw bone is the ___________________________________. . The cheek bone is the _____________________________________ bone. The horizontal parts of _________________ bones unite to form posterior part of the hard palate Question

True or False

Sphenoid, zygomatic, maxillary and frontal bones are some of the bones which make up the orbit. There are two nasal bones. There is one parietal bone in the skull. The nasal bones contain all the paranasal sinuses. Most bones of the skull are classified as flat bones. The mandible is an example of an irregular bone.

The condyle of the mandible is at the (superior or inferior) end of the ramus. The mandibular foramen is on the (lateral or medial) surface of the ramus. The mental protuberance is at the (anterior or posterior) end of the mandible. Name in order from anterior to posterior, the three bones which form the top/back of skull _________________ _________________ _____________________ Briefly describe the location of the hyoid bone. _______________________________________________________________________ What makes the hyoid bone unique when compared to the other bones of the axial skeleton? ________________________________________________________________________ What structure of the oral cavity is attached to the hyoid bone by muscles? _____________________

Question

True or False

The mandible articulates with the maxilla.

T - F

BIO4324 Head and Neck Anatomy Weeks 3-4 Lecture NotesAcademic Year 2018-2019 10

There are 2 frontal bones in the skull.

T - F

There are 2 parietal bones in the skull.

T - F

The sphenoid bone forms part of the eye orbit.

T - F

The occipital bone makes the framework of the lower, posterior part of the skull.

T - F

The mandible is the superior jaw bone.

T - F

The temporal bone articulates with the mandible.

T - F

There are 2 temporal bones in the skull.

T - F

The sphenoid articulates with the mandible.

T - F

The mandible is a single bone.

T - F

The foramen magnum is an opening in the occipital bone.

T - F

There are 2 occipital bones in the skull.

T - F

There are 2 nasal bones in the skull.

T - F

The zygomatic bone articulates with the temporal bone.

T - F

The nasal bone articulates with the maxilla.

T - F

The zygomatic arch is formed by the zygomatic and occipital bones.

T - F

BIO4324 Head and Neck Anatomy Weeks 3-4 Lecture NotesAcademic Year 2018-2019 11...