The function of incisors or “nippers” is to cut grass at ground level. This is the beginning of the horses digestive process
The horse has 12 deciduous incisors (baby teeth that will be shed) and 12 permanent incisors that will replace them.
The normal horse’s upper jaw may appear to protrude further than the lower jaw although this will only be by a couple of millimetres. When the horse lowers its head to eat, the lower jaw moves forward and the lower incisors will be in true opposition to the upper incisors.
If a horse has an upper jaw that protrudes extensively beyond the lower jaw this condition is referred to as a Parrot mouth. Alternatively, if the lower jaw extends beyond the upper jaw, this is referred to as a Sow mouth or a Monkey Mouth condition.