the skull forensic anthropology. the skull total # - 22 total # - 22 8 paired, 6 unpaired 8 paired,...

The skull

Forensic anthropology

The Skull Total # - 22

8 paired, 6 unpaired Cranium – skull without mandible Calvarium – cranium without face Sutures: serrated and interdigitated The only moveable (synovial) joints

Occipital condyles and C1 TMJ

The Frontal Bone

Unpaired Recognizable by the sinuses Articulations?

Individual identification: unfused frontal (called metopic suture), variable sinuses

2 growth centers (R&L)

Is the frontal useful?

Yes!

Age – the metopic suture fuses ~2-4 years

Sex determination Supercilliary arch / frontal boss Supraorbital margin Temporal line

The Parietals Paired Rectangular shaped

Articulations?

Individual ID: variable sutures and foramen placement

Growth – single growth center

Are the parietals useful?

Mostly for age

General thickness becomes more uniform with adulthood

Fuses with parietal only with advanced age

The occipital Unpaired Ovoid with a big hole in it… Articulations?

Individual ID: Inca bone p. 50 (usually triangular or rectangular)

Growth - 4 parts: squamous, 2 laterals, basial (pars basilaris usually survives)

Is the occipital useful? Yes!!!

Age Pars basilaris

Fuses to squamous portion at 1-3 years Fuses to the rest at 5-7 years Fuses to sphenoid during mid teens

Sex External occipital protuberance Superior and inferior nuchal lines

The temporals

Paired Circular (with a large process for ear canal) Articulations?

Individual ID: suture variation

Growth – 3 parts: petrous, squamousal, tympanic ring)

Are the temporal useful?

Age The 3 parts are joined by ~5 years old

Sex Mastoid process

The sphenoid

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

Paired facial bones Triangular with maxillary, frontal, and temporal

processes Forms lateral wall of orbit Articulations?

Individual ID: variable sutures

Growth – 1 center,

Are the zygomatics useful?

Age Zygomatics fully formed by 2-3 years old

Race Suture pattern of the zygomaxillary junction

generally related to race

The ethmoid Found at the base of the frontal, anterior to the

sphenoid Very uniquely shaped Forms part of the orbit (medial wall)

Need to know Crista galli Perpendicular plate

Other bones of the face Not typically found,

not particularly useful in ID

The NASALS

The inferior nasal conchae (found in nasal aperture internally, posterior to the nasal bones

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

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?

Yes!

Age – TEETH!!!

Race: Width of nasal aperature Projection of nose and mouth Dental arch shape

The Maxillae 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?

Yes!

Age – TEETH!!!

Race: Width of nasal aperature Projection of nose and mouth Dental arch shape

The mandible Single bone U-shaped with vertical processes Contains teeth: functions largely as muscle

attachments (chewing muscles and tongue) and holds teeth

Individual ID: variable shape of jaw, teeth

Growth – 2 centers

Is the mandible useful?

YES!!

Age 2 halves fuse by 6-8 months

Sex Mental protuberance Gonial angle

The mandible 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? YES!!

Individual ID: variable shape of jaw, teeth

Growth – 2 centers

Age 2 halves fuse by 6-8 months

Sex Mental protuberance Gonial angle

Teeth!!!!!

Directional terminology Labial: toward lips Buccal: toward cheek Lingual: toward tongue

Mesial: toward midline Distal: toward back of mouth, away from midline

Teeth We talk about teeth in

quadrants (RU, RL, LU, LL), 8 in each

Short hand examples… Upper, lower, left, right

4 types Incisors (2) Canines (1) Premolars (2) Molars (3)

http://en.wikipedia.org/wiki/Incisor

4 typesIncisor, Canine, Premolar, Molar

www.dkimages.com

Incisors

8 total

Anterior teeth Single straight edge with no cusps Single root

http://www.nature.com/bdj/journal/v203/n10/thumbs/bdj.2007.1059-f1.jpg

Canines

4 total

Distal to incisors Single cusp Single root

www.uic.edu/classes/orla/orla312/CanMand.gif

Premolars 8 total

Distal to canine

2 cusps Buccal root larger

1-2 roots

http://www.uic.edu/classes/orla/orla312/PreMandTwo.gif

Molars

12 total

Multiple cusps Multiple roots

Complex morphology for chewing and grinding

Upper molars generally have more roots

www.uic.edu/classes/orla/orla312/MolarDownOne.gif

http://www.uic.edu/classes/orla/orla312/MOLARS%20upper.htm www.tpub.com