i believe you would want to pull the front teeth on the lower jaws.
to age deer by looking at them you must look at several things. # of teeth, wear, plaque build up, etc. also, you always look at the teeth on the lower jaws.
a yearling deer will only have 5 teeth
a 1 1/2 year old deer the 2nd tooth from the front on the bottom jaw will be a tricuspid, 3 parts, rather than a bicuspid, 2 parts. sometimes it will appear to be busted or halfway in also.
from here it gets tricky. always look at lower jaws
2 1/2 generally have no plaque build up and their molars are sharp to the touch and there is a distinct difference in the height of the crowns on either side of the teech. the crowns closer to the tongue will be much higher.
3 1/2 gets mild plaque bild up and the teeth begin to wear down slightly
4 1/2 have fairly heavy build up and the ridges on the crowns begin to become level with each other
5 1/2 + are VERY difficult to tell as they all tend to look the same. here it is easiest to send the front teeth from the lower jaw in and have them cut cross sections and look at them. you must also take into consideration where you are geographically speaking. if the area you'er in has high sand content in the soil then you're naturally going to get more tooth wear. the opposite can be said about areas where the soil is softer.
another thing to help age is to look at body size, length, hoof size, hair color, head length, etc. these things can help out but do not give accurate aging without looking at the teeth. i've seen bucks that are in the 140 range and absolutely massive but only be 2 1/2 years old when you look at their teeth.
hope this helps.
