Unit 2 Aging Teeth Flashcards
Horse teeth aging
x
accuracy is highest until
5 years of age; should be able to estimate within about 6 months
what are the teeth used primarily for aging
lower incisors
aging accuracy declines after
8-10 years of age
younger horses angle of incisors
vertical angle
older horses angle of incisors
horizontal
step 1 of aging horse teeth
determine whther any deciduate incisors are present;
deciduous incisors are ___ shaped
cup (smaller and whiter in color)
step 2
if any deciduate incisors are present, the horse is less then 5 years of age
eruption of DI1
6 days
eruption of DI2
6 weeks
eruption of DI3
6 months
yearling upper and lower 3rd incisors
have less contact with each other (less wear)
two-year old upper and lower 3rd incisors
have greater conact with each other (greater wear)
erpuption of I1
At 2.5 yrs, in wear at 3 yrs
eruption of I2
3.5 yrs; wear at 4 yrs
eruption of I3
at 4.5 yrs; wear at 5 yrs
eruption of canines teeth
3.5-5 yrs
step 3
if no deciduate incisors are present, the horse is older than 5 years of age
if tooth is wider than tall
5-9 yrs
disappearance of cups at I1
6yrs
disappearance of cups at I2
7 yrs
disappearance of cups at I3
8 yrs
tooth is approximately square
9-10 yrs
tooth is taller than wide
> 11 yrs
oval to round incisors
5-9 yrs
round to triangular incisors
10-15 yrs
triangular to biangular incisors
16-20 yrs
I1 dental star
8 yrs
I2 dental star
9 yrs
I3 dental star
10 years
disappearance of enamel ring I1
11-12 yrs
disappearance of enamel ring I2
12-13 yrs
disappearance of enamel ring I3
12-14 yrs
hook on upper third incisors
7 yrs and 11-13 yrs
galvaynes groove on upper third incisors
x
appears on tooth at gum line
9-10 years
halfway down tooth
15 years
along entire tooth
18-20 yrs
on distal half of tooth
25 years
small notch oat distal edge of tooth
30 yrs
eruption of p1
5-6 months
p2
2.5 yrs
p3
3 yrs
p4
4 yrs
m1
1 yr
m2
2 yrs
m3
3.5-4 yrs
ruminant deciduous formula
2 (I 0/3, C 0/1, P 3/3, M 3/3) = 32
Ruminant permanent formula
2 (I 0/3, C 0/1, P 3/3, M 3/3) = 20
2wks to 1 month
all deciduous incisors erupted (all 4 can be erupted at birth)
1.5 to 2 yrs
permanent I1
2-2.5 yrs
I2 erupted, I1 in wear
3-3.5 yrs
I3 erupted
3.5 yrs
I3 in wear
3.5 to 4 yrs
I4 erupted
5 yrs
I4 in wear
6 yrs
I1 is level
7 yrs
I2 is level
8 yrs
I3 is level
9 yrs
I4 is level
10-12 yrs
I1 through I3 are pegs. I4 level
15 yrs
incisors are small, rounded pegs
> 15 yrs
some/all incisors missing; remaining inscisors small, rounded pegs
6 months
molar 1
1-1.5 years
molar 2
2-2.5 years
molar 3
