First of all,Congrats on a fine buck!!!
Even experts have a tough time aging by teeth. It's still a very inexact science.
The teeth are still relatively sharp. The sharpness or worn edges is far more telling than a lot of exposed dentin. I'd age this guy at 2 1/2 to 3 1/2 at best. The deers diet and the type of soil in the area can cause wide variances in tooth wear
Mass is the most telling indicator of age in the antlers (even less reliable though) and his mass makes me lean toward 2 1/2
What is the distance between the front corner of the eye and the corner of the nostril ?