5 Anatomy of a Jawbone Back Front Lingual Crests (tongue side) Back Cusp IncisorsBuccal Crests(cheek side)
6 Anatomy of a Jawbone Enamel Dentine (white) (dark) Premolars Molars P1
7 Tooth Eruption and Wear Technique Based on two processes:1. Tooth eruption is the process of gaining additional teeth over time and replacing temporary teeth with permanent ones.2. Tooth Wear – is the process of tooth erosion over time with age.
8 Tooth EruptionWhitetails are born with three temporary teeth (premolars). From this age until they are about months old, they replace these temporary teeth with permanent teeth and also gain three additional permanent molars.All whitetails 18 months of age or older should have six permanent teeth on each side of their lower jaw.
10 Tooth Eruption and Wear Technique AdvantagesRequires no specialized equipment, costs nothing, and can be done at campCan be learned by most deer hunters and managers with sufficient practiceDisadvantagesMore subjective and highly dependant upon ability of individual agerBelieved to be somewhat affected by soil and habitat quality
11 Separate Into Three Age Classes Aging – Step 1Separate Into Three Age ClassesFawn (6 months)- three or four total jaw teeth2. Yearling (1 ½ years old)- six teeth, but temporary third premolar (P3)Adult (2 ½ years old)-six teeth, but all permanent
12 Temporary vs. Permanent Premolars (one crest)Temporary premolar(three crests)
13 Separating Deer Into Three Age Classes AdultM3P1M2M1P3P2YearlingM3P2P1M2M1P3FawnP1P3P2M1
14 Fawn (6 months old)Key – Only 3 or 4 fully erupted teeth
15 Yearling (1 ½ years old) Keys – 6 teeth and temporary 3rd premolar Generally fully eruptedNote permanent tooth erupting, may already have replaced temporary tooth if harvested late in season
16 Estimating Age of Adults Based on Wear Aging – Step 2Estimating Age of Adults Based on WearThis technique is based on the width of the dentine on the molars compared to the width of the surrounding enamel.
17 Question -Is the dentine (dark) on the lingual crests approximately twice as wide or wider than one strip of surrounding enamel (white)?NoYes
18 2 ½ years oldNoM1P3Keys – six teeth, permanent 3rd premolar (P3) and dentine not twice as wide as surrounding enamel on the first molar (M1)
19 3 ½ years oldNoYesM2M1Keys – The dentine is twice as wide as the surrounding enamel on first molar (M1) but not the second molar (M2). The back cusp is starting to show noticeable wear.
20 4 ½ years oldNoYesYesM3M2M1Keys – The dentine is twice as wide as the surrounding enamel on the first and second molars (M1 & M2) but not the third (M3). The back cusp is also starting to form a “cup.”
21 5 ½ - 6 ½ years oldYesYesYesM3M2M1Keys – The dentine is twice as wide as the surrounding enamel on the first, second and third molars (M1, M2 & M3). The back cusp is heavily cupped and slanting.