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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
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The skull Forensic anthropology
The Skull • Total # - 22 • 8paired, 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
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) Other bones of the face
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
8 total Distal to canine 2 cusps Buccal root larger 1-2 roots Premolars 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