Facial and Skull bones Flashcards
The skull with the fleshy parts added, which includes the face.
- The skull is the bony framework of the head composed of the cranial and facial bones.
- Decapitation- includes the skull and the fleshy parts of the face.
The Head
- Protect the brain
- Support the jaws
- Serve as an attachment for muscles
- Give form to the head
Purpose of the Skull
- Oval from 3 views. (Front, side, top [crown]).
- Width is 2/3rds its length.
- Variations of form are because of enlarged width or length.
Geometric Form of The Normal Skull
- Bone thickness: Thicker
- Size of bones: Larger, relatively large
- Prominence of eminences: More
- Frontaonasal angle: Sharp, angular
- Supraorbital ridges: Prominent
- Forehead: Slopes backward
- Surface cheekbone: Rough, concave
- Mandible tip (chin): Squarer
- Foramen magnum: Large, long
- Mastoid process: Large
Male skull features
- Bone thickness: Thinner
- Size of Bones: Smaller, relatively small
- Prominence of eminences: Less
- Frontalnasal angle: Smooth curve
- Supraorbital ridges: poorly developed
- Forehead: Nearly vertical
- Surface cheekbone: smooth, flat
- Mandible tip (chin): Pointed
- Foramen magnum: smaller, round
- Mastoid process: small
Female Skull Features
- Reduction in the vertical length of the face.
- Alteration of the angles of the jaw.
Changes Resulting From The Loss of Teeth
Skull bone classification in the study of osteology.
Flat
The bones of the skull are locked together by the means of these.
- Exception: Lower jaw (mandible) is held by muscles and tendons.
Sutures
- Cranium
- Face
2 Major Sections of The Skull
Encloses the brain (larger simpler bones).
Cranium
More complex in form.
Face
Studies the parts of the bones which influence surface form or contribute to a restoration.
Restorative Art
Located at the anterior part of the base of the skull and binds the other cranial bones together.
Sphenoid
(No restorative art significance, not surface bone)
A horizontal plate that forms the roof of the nasal cavity and closes the anterior part of the base of the cranium.
Ethmoid
(No restorative art significance, not surface bone)
- Cradle for the brain.
- Lowest part of the back and base of the cranium.
- Contains the Foramen Magnum
- Articulates with the parietal bone at lambdoidal suture and the Termporal bone at the squamosal suture.
Occipital Bone
Large opening which permits entry of the spinal cord. Through which the spinal cord, spinal arteries, and nerves pass. It is located midway between the two mastoid processes.
- Value in a restoration- may be used to restore a decapitation.
Foramen Magnum
Form the superior portion of the sides and back of the cranium as well as 2/3rds of the roof of the cranium.
- Articulates with the Occipital bone at the lambdoidal suture, temporal bone at the squamosal suture, frontal bone at the coronal suture, and the opposite side parietal at the sagittal suture.
- Parietal eminence
- saggital suture
- Vertex
Parietal Bones (2)
Marked convexities on the outer surfaces of the partietal bones.
- Widest part of the cranium. It is measured between the two of these.
Parietal Eminence
Where both parietal bones join at the highest point of the cranial dome.
Sagittal Suture
The highest part of the cranium.
Vertex
Create the lower portion of the sides and base of the cranium. They are located inferior to the parietal bones and anterior to the occipital bone.
- Articulates with the parietal bone at the squamosal suture; Occipital bone at lambdoidal suture; Greater wing of the sphenoid bone.
Contains:
- Squama
- Zygomatic arch
- mandibular fossa
- Mastoid process
- external auditory meatus
Temporal Bones (2)
(Like a fish scale, which is this word’s meaning). The thin, superior part of the temporal bone. The temporal cavity is immediately lateral (outside) this, and this space houses the temporalis muscle, which, especially in the elderly or emaciated case, may atrophy and dehydrate, causing it to shrink, as in sunken temples, and require tissue building, however, only after consulting a photograph of the deceased.
Vertical surface of temporal bone.
- Zygomatic arch
- Mandibular fossa
Squama
A long, thin, arched process extending anteriorly from the squama to the zygomatic bone. It lies above the external auditory meatus.
- Widest part of the face is between the arches.
- Divides the ears length into two equal parts (halves). May be used to locate the correct position of a modeled ear.
Zygomatic Arch
A small oval depression or socket on the underside of the temporal bone. The condyle of the madible articulates in this depression.
- Socket for the mandible.
- Lies directly anterior to the ear passage (external auditory meatus).
Mandibular Fossa
A rounded projection of the interior portion of the temporal bone.
- Posterior part of the temporal bone.
- Physiognomically- under the lobe of the ear.
- Serves as the attachment of the sternocleidomastoideus muscle.
- The widest part of the neck.
Mastoid Process
- Opening of the ear passage.
- Is the keystone for accurate location of a modeled ear.
- Located in front of the mastoid process.
External Auditory Meatus
- Anterior 1/3 of the cranium
- Forms the forehead, parts of the eye socket and most of the anterior portion of the roof of the skull (cranial floor)
- Forehead
- Crown
- Hairline
- Eminences
- Articulates with the parietal bones at the coronal suture.
Frontal Bone (1)
From the eye sockets to the frontal eminences.
Forehead
From the frontal eminences to the parietal bones. An area at the top of the cranium delineated by connecting four points together. The four points are the two frontal eminences and the two parietal eminences.
- These four points are where a king’s crown would rest.
Crown
Located on the crown of the head, above the frontal eminences. “Normal”
Hairline
- Frontal
- Superciliary arch
- glabella
- supraorbital margin
Eminences of the Frontal Bone
Upper part of the forehead. Rounded prominences on either side of the median line and a little inferior to the center of the frontal bone.
- A warm color area of the face
Frontal Eminences (2)
Inferior part of the forehead, lie just superior to the medial ends of the eyebrows (supercilia).
Superciliary Arch (2)
A smooth elevation betwen the superciliary arches on the inferior part of the frontal bone immediately above the root of the nose.
- The root is the point at which the two nasal bones touch the frontal bone. It is inferior to the glabella.
Glabella
The upper (superior) rim of the eye socket.
Supraorbital Margin (2)
Slightly raised curving ridge.
- Marks the end of the forehead and the beginning of the temporal region.
Line of The Temple
- Occipital (1)
- Parietal (2)
- Temporal (2)
- Frontal (1)
- Sphenoid
- Ethnoid
Bones of the Cranium
- Zygomatic Bone (2)
- Nasal Bones (2)
- Maxilla (2)
- Mandible (1)
Exernal Facial Bones
Diamond-shaped bones that form the cheekbones. located on the frontal and lateral planes of the face. The bones form part of the inferior and lateral surfaces of the orbital cavity.
- Articulates wtih: Temporal process of the zygomatic. Embryonically, this is made from three primary ossification centers which grow together to form the arch. When the arch is completely fused, it has three parts from anterior to posterior (1. zygomatic bone, 2. temporal process of zygomatic, 3. Zygomatic processs of temporal, which completes the arch attaching it to the temporal bone)
- Location (physiognomically) - Slightly inferior and lateral to the outer corner of the eye.
- The greatest width of the anterior plane of the face is measure between the centers of both of these.
- Acts as an area for rouge cosmetics
Zygomatic Bone (2)
- Lies directly inferior to the glabella.
- Create the bridge of the nose and a dome over the superior part of the nasal cavity
- Its frontal and lateral surfaces widen as they descend.
- From a profile view:
- The degree of slant (inclination) is important in a wax restoration.
- They dip posteriorly below the glabella (root).
- The tissue covering is thin over these bones- the outer form is a repeat of the form of the bony contour.
- Articulates with each other, forming bridge of nose and, with the frontal bone, forming the root of the nose, which is specifically where the frontal bone meets the two nasal bones
Nasal Bones (2)
The orifice (opening) in the face bounded by the margins of the nasal bones and the maxilla. Made up of two irregular-shaped spaces separated by a cartilage, which makes up a small part of the septum.
- This area is used as a hidden injection point for tissue building the face.
Nasal Cavity
- Creates the upper jaw
- Form the skeletal base for most of the superior portion of the face, anterior roof of the mouth, sides and floor of the nasal cavity, and floor of the orbits.
- Articulate with each other at the medial line below the nasal cavity.
- Nasal Spine
- The nasal spine creates the bony anatomical limit of the nose.
- alveolar process
- Palatine process
- Zygomatic process
- Dental prognathism
Maxilla (2)
The small, bony spur which projects at the base of the nasal cavity.
Nasal Spine of The Maxilla
The most Inferior part of the nose.
Columna Nasi
Sockets that the teeth set in.
- The thick, spongey bone portion which projects from the lower surface of the maxilla and contains the sockets for the teeth.
- Loss of teeth- reduces the height of the upper jaw as the alveolar processes are absorbed.
Alveolar Process
Forms the anterior part of the hard palate of the mouth. Part of the nasal cavity and part of the orbital cavity.
Palantine Process
Where the temporal bone joins the zygomatic bone.
Zygomatic Process
Can occur in the maxilla.
Dental Prognathism
Bilaterally, there is this kind of curvature of the bones and teeth.
Horseshoe
- The horseshoe-shaped bone forming the lower jaw. It consists of two portions- the body and the ramus.
- Articulation- held in place by muscles and tendons. It articulates in the mandibular fossa of the temporal bone.
- Body (1)
- Ramus (2)
- Coronoid process
- Condyle
- Angle
- Mental Eminence
- Incisive Fossa
- Prognathism
Mandible (1)
- Horizontal portion of the jawbone.
- Bilaterally- the form of the body is that of a horseshoe.
- Lowest part of the lower jaw
- Contains the alveolar processes for the teeth
Body
- Vertical portion of the jawbone.
- Terminates superiorly in 2 processes:
- Crornoid process
- Condyle
- Wide, flat, and quadrilateral in shape.
Ramus
A thin, flattened process projecting from the anterior portion of the upper border of the ramus. Serves as an insertion of the Temporalis muscle of mastication (chewing) from the temporal cavity above, which may need injections of tissue builder.
- Lies anterior and has no influence on surface form.
Coronoid process
The rounded process which rests in the mandibular fossa in the temporal bone; a rounded eminence at the articulating posterior process of the ramus.
- Can be associated with dislocated jaw
- .Aids in an ear restoration because it lies anterior to the ear passage.
Condyle
The angle formed by the junction of the posterior edge of the ramus and the inferior surfaces of the body of the mandible.
- Where the ramus joins the inferior border of the body.
- Frontal View- will greatly influence the geometric form of the head. (Its head shape: triangular, oval, diamond, etc.)
Angle (2)
Measured by a straight line betwen the two angles of the mandible and is used in photographic analysis for restoration.
- In a photograph, is to be compared to the bizygomatic width and the bimandibular width along with the length of the head in order to reproduce, in wax, the correct geometric head shape such as round, oval, square, oblong, diamond, triangular, or inverted triangle.
Bimandibular Width
- Birth - 175
- 4 years- 140
- Adult- 110-120
- Old Age- 140 with loss of teeth and absorption of alveolar processes.
Degree of Obtuseness During a Lifetime
The point of the chin; A triangular projection on the inferior of the anterior mandible.
- Triangular eminence of the chin.
- The base of the eminence is slightly concave but at each end is a prominent mental tubercle.
- These influence the inferior border of the chin and jawline.
Mental Eminence
Dent on top of the chin.
- A depression of the lower jaw below the 4 front incisor teeth. (between the mental eminence and the incisor teeth)
- Is responsible for the recession at the center of the lower lip to the top of the chin.
Incisive Fossa
Projection of the jaw(s) beyond the projection of the forehead.
- A condition in which the jaw(s) project anteriorly beyond the superior part of the face.
- May be a result of:
- The alveolar process
- The teeth
- The jawbones
Prognathism
- Alveolar
- Dental (buck teeth)
- Infranasal
- Mandibular
- Maxillary
Types of Prognathism
Sockets of the teeth are inclined.
Alveolar Prognathism
Oblique insertion of the teeth; front teeth protrude.
Dental Prognathism (Buck Teeth)
The base of the nasal cavity protrudes abnormally.
Infranasal Prognathism
The inferior jaw (mandible) protrudes.
Mandibular Prognathism
The superior jaw (maxilla) protrudes.
Maxillary Prognathism
True or false:
Buck teeth may be discovered where there is no prognathism.
True
- Vomer (1)
- Lacrimal (2)
- Palantine (2)
Bones of the Face that are Not Surface Bones
A single bone located along the midline within the nasal cavity.
- Forms part of the septum of the nose.
- Thin and varies in different individuals
- Frequently is bent slightly to one side or the other, making the nasal chambers an unequal size.
Vomer Bone
Two bones located in the medial wall of each orbit between the ethmoid and maxillar bones.
- They somewhat resemble a fingernail in shape.
Lacrimal Bones
Consist of two bones that are located at the back part of the nasal cavity behind the maxille. These bones help form the back part of the roof of the mouth, part of the floor and outer wall of the nasal cavity, and a very small portion of the floor of the orbit.
Palantine Bones
