The skull
Forensic anthropology
The Skull
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Total # - 22
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8 paired, 6 unpaired
Cranium – skull without mandible
Calvarium – cranium without face
Sutures: serrated and interdigitated
The only moveable (synovial) joints
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Occipital condyles and C1
TMJ
The Frontal Bone
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Unpaired
Recognizable by the sinuses
Articulations?
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Individual identification: unfused frontal
(called metopic suture), variable sinuses
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2 growth centers (R&L)
Is the frontal useful?
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Yes!
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Age – the metopic suture fuses ~2-4 years
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Sex determination
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Supercilliary arch / frontal boss
Supraorbital margin
Temporal line
The Parietals
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Paired
Rectangular shaped
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Articulations?
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Individual ID: variable sutures and foramen
placement
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Growth – single growth center
Are the parietals useful?
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Mostly for age
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General thickness becomes more uniform with
adulthood
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Fuses with parietal only with advanced age
The occipital
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Unpaired
Ovoid with a big hole in it…
Articulations?
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Individual ID: Inca bone p. 50
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(usually triangular or rectangular)
Growth - 4 parts: squamous, 2 laterals, basial
(pars basilaris usually survives)
Is the occipital useful?
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Yes!!!
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Age
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Pars basilaris
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Fuses to squamous portion at 1-3 years
Fuses to the rest at 5-7 years
Fuses to sphenoid during mid teens
Sex
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External occipital protuberance
Superior and inferior nuchal lines
The temporals
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Paired
Circular (with a large process for ear canal)
Articulations?
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Individual ID: suture variation
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Growth – 3 parts: petrous, squamousal,
tympanic ring)
Are the temporal useful?
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Age
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The 3 parts are joined by ~5 years old
Sex
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Mastoid process
The sphenoid
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Unpaired
Butterfly shaped
Articulations?
Growth – many centers fuse by birth into 3
parts (wings separated by body) which fuse by
1 year old
The zygomatics
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Paired facial bones
Triangular with maxillary, frontal, and temporal
processes
Forms lateral wall of orbit
Articulations?
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Individual ID: variable sutures
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Growth – 1 center,
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Are the zygomatics useful?
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Age
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Zygomatics fully formed by 2-3 years old
Race
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Suture pattern of the zygomaxillary junction
generally related to race
The ethmoid
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Found at the base of the frontal, anterior to the
sphenoid
Very uniquely shaped
Forms part of the orbit (medial wall)
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Need to know
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Crista galli
Perpendicular plate
Other bones of the face
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Not typically found, not
particularly useful in ID
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The NASALS
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The inferior nasal
conchae (found in nasal
aperture internally,
posterior to the nasal
bones
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The lacrimals –tear ducts
The palatines – at back of
mouth, found behind
palatine process of
maxillae
Vomer – small wedge of
bone btw pterygoid
processes of sphenoid
(bisects nasal cavity)
The teeth
The Maxillae
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Paired, facial
Contribute to structure of eyes, nose, mouth
3 processes; frontal, zygomatic, palatine
Articulations?
Individual ID: dental arch, teeth, prominence
of mouth and nose
Are the maxillae useful?
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Yes!
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Age – TEETH!!!
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Race:
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Width of nasal aperature
Projection of nose and mouth
Dental arch shape
The Maxillae
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Paired, facial
Contribute to
structure of eyes,
nose, mouth
3 processes; frontal,
zygomatic, palatine
Articulations?
Individual ID:
dental arch, teeth,
prominence of
mouth and nose
Are the maxillae useful?
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Yes!
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Age – TEETH!!!
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Race:
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Width of nasal aperature
Projection of nose and mouth
Dental arch shape
The mandible
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Single bone
U-shaped with vertical processes
Contains teeth: functions largely as muscle
attachments (chewing muscles and tongue) and
holds teeth
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Individual ID: variable shape of jaw, teeth
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Growth – 2 centers
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Is the mandible useful?
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YES!!
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Age
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2 halves fuse by 6-8 months
Sex
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Mental protuberance
Gonial angle
The mandible
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Single bone
U-shaped with vertical processes
Contains teeth: functions largely as muscle
attachments (chewing muscles and tongue) and
holds teeth
Is the mandible useful?
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YES!!
Individual ID: variable shape of jaw, teeth
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Growth – 2 centers
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Age
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2 halves fuse by 6-8 months
Sex
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Mental protuberance
Gonial angle
Teeth!!!!!
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Directional terminology
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Labial: toward lips
Buccal: toward cheek
Lingual: toward tongue
Mesial: toward midline
Distal: toward back of mouth, away from midline
Teeth
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We talk about teeth in
quadrants (RU, RL, LU,
LL), 8 in each
Short hand examples…
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Upper, lower, left, right
4 types
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Incisors (2)
Canines (1)
Premolars (2)
Molars (3)
http://en.wikipedia.org/wiki/Incisor
4 types
Incisor, Canine, Premolar, Molar
www.dkimages.com
Incisors
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8 total
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Anterior teeth
Single straight edge with no cusps
Single root
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http://www.nature.com/bdj/journal/v203/n10/thumbs/bdj.2007.1059-f1.jpg
Canines
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4 total
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Distal to incisors
Single cusp
Single root
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www.uic.edu/classes/orla/orla312/
CanMand.gif
Premolars
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8 total
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2 cusps
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Distal to canine
http://www.uic.edu/classes/orla/orla312/
PreMandTwo.gif
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Buccal root larger
1-2 roots
Molars
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12 total
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Multiple cusps
Multiple roots
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Complex morphology for chewing and grinding
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Upper molars generally have more roots
www.uic.edu/classes/orla/orla312/MolarDownOne.gif
http://www.uic.edu/classes/orla/orla312/MOLARS%20up
per.htm
www.tpub.com