The following table gives a rough guide to the eruption times of the horses teeth. The teeth are numbered from 01, the central incisor through to 11, which is the rear molar.
Tooth
Deciduous
Permanent
01 (Incisor)
Less than 1 week
2 ½ years
02 (Incisor)
4 – 6 weeks
3 ½ years
03 (Incisor)
6 – 9 months
4 ½ years
04 (Canine)
Between 4 and 5 years (if present)
05 (Wolf Teeth)
5 to 6 months (if present)
06 (Premolar)
Birth to 2 weeks
2 ½ years
07 (Premolar)
Birth to 2 weeks
3 years
08 (Premolar)
Birth to 2 weeks
4 years
09 (Molar)
9 to 12 months
10 (Molar)
2 years
11 (Molar)
3 ½ years
The best way to age a horse is by the eruption dates and appearance of the lower incisors. There will be marked differences between different horses however and so ageing by teeth can not be totally accurate.
The eruption of the lower incisors is a relatively accurate way to age a horse and is usually accurate to within 6 months. After this however, we have to look at the appearance of the surface of the tooth. As the tooth is worn down, it will change in its shape and the appearance at the occlusal surface. The diagram below shows how the appearance of the occlusal surface will change as the tooth wears down. As the tooth wears down, the odontoblast cells in the pulp chamber produce secondary dentin. This absorbs the pigment from the horse's food and can be seen as the Dental Star.
