Forensic anthropology The skull Forensic anthropology
The Skull Total # - 22 Cranium – skull without mandible 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 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) 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 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 Sex 2 halves fuse by 6-8 months 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 types Incisor, 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 2 cusps 8 total 1-2 roots Distal to canine Buccal root larger 1-2 roots 8 total Distal to canine 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