Dentition – Deciduous teeth There are 20 primary teeth (10 at every jaw): 8 incisors, 4 canines and 8 primary molars. By 4 months in utero: Teeth begin to form in bone By Age 2: All deciduous or ‘baby’ teeth have erupted

Dentition – Permanent Teeth There are 32 permanent teeth (16 at every jaw): 8 incisors, 4 canines, 8 premolars, and 12 molars By Age 6: Permanent teeth have started to erupt By Age 12: Second set of molars have emerged Age 17-24: Wisdom teeth have erupted

Dentition The number of teeth of each type of tooth is written as a dental formula for one side of the mouth. The teeth are numbered in order: Incisors, Canines, Premolars, Molars I:C:P:M

Juvenile skull less than 6-7 years old. Dentition: 2:1:2 2 incisors 1 canine 2 premolars 0 molars

Dentition: 2:1:2:2 Skull from a 12 year old male. 2 incisors 1 canine 2 premolars 2 molars Wisdom tooth is under the surface of the gum

Adult male skull Dentition: 2:1:2:3 2 incisors 1 canine 2 premolars

Human developmental phases and general characteristics used for aging Perinatal Neonate Infant/toddler Late childhood Adolescence Early adulthood Middle and late adulthood

Perinatals - before birth The age of perinatals, individuals not yet born, can be determined by looking at bone size. This is a fairly accurate estimate due to the fact malnourishment will not affect growth; the fetus will take necessary nutrients from the mother.

Neonates ~ 0-6 or 7 months Prove very difficult to accurately determine the age because of individual variation of development (genetics & nourishment). Neonates have no teeth Areas of the skeleton have not fused together (especially the cranium and pelvis).

Infants and toddlers 6 or 7 months ~ 2 years All (20) deciduous teeth erupted by age 2. Permanent teeth (under ‘baby’ teeth) start to form at birth, thus the formation of permanent teeth is a relatively good age determinant. Some ossification has begun, this is highly variable at this age

Late childhood ~ 6 years -11 years Late childhood is when the permanent teeth begin to come in. More bones begin to ossify. Second set of molars come in at about age 12.

Adolescence ~12- 18 years Adolescence shows increased long bone length and fusion of the ends (or cap) to the shaft. This epiphyseal union/fusion is a particularly useful age technique. (see skeletal diagrams for age references).

Age range ~ 20 – 35 ish Young adults and older adults have several methods of age determination: closure of the cranial sutures; morphology of rib-ends, pubic symphysial microstructure of bone and teeth; wear on teeth, incremental layers of cementum

Age of epiphyseal fusion. First number is approximate age at which fusion first begins. Second number is approximate age at which fusion is complete.

Practice Q’s Region A has just begun to fuse Region B, fusion is approximately 90% complete. There is a complete epiphysial union at location C. Fusion at distal end of radius and ulna is approximately 50-60%. What is the approximate age of this person? Diagram of human shoulder and arm

Answer… Age 18-20 Age range 18-25 Age range 15-19 Age range 13-18

Practice Q’s… Description of partial skull and partial pelvis found in a remote wooded area: Skull - coronal suture is approximately 60% fused, lamboidal suture is fused and semi smooth, frontal area (forehead) has a 40 0 angle. The subpubic angle is approximately 50 0, and the pubic bone (pubic symphysis) is completely fused. What is the sex and age of this individual?

Answer…. Skull - coronal suture is approximately 60% fused,( age range 30-35) lamboidal suture is fused and semi smooth (age range closes at 30, get more snooth over time), frontal area (forehead) has a 40 0 angle (male less than 90 0). The subpubic angle is approximately 50 0,(male 50-800) and the pubic bone (pubic symphysis) is completely fused (age 20-23) .

Adult dentition and age range of tooth eruption

Frontal view of adult dentition, numbers for identification and tooth name.

Maxilla of female found in wooded area after a suicide. Did this woman have her wisdom teeth?

Maxilla of female found in wooded area after a suicide. Did this woman have her wisdom teeth? YES 2:1:2:3