What is it called when the lower jaw is shorter than the upper jaw?

When the lower jaw is shorter than the upper jaw, this condition is commonly referred to as "Parrot Mouth." In equine terms, this dental arrangement can lead to various issues such as improper chewing, which can affect a horse's nutritional intake and overall health. The term "Parrot Mouth" specifically describes this dental structure as it resembles the beak of a parrot, where the upper jaw extends beyond the lower jaw.

In contrast, the term "Underbite" is generally used to describe a situation where the lower jaw protrudes beyond the upper jaw, which does not apply here. The other terms, "Overbite" and "Monkey Mouth," are also utilized in different contexts but do not accurately describe the condition of a shorter lower jaw. "Monkey Mouth" is sometimes confused with "Parrot Mouth," but it usually refers to a specific morphological difference where the lower jaw is either normal or longer, leading to different dental alignments. Understanding these distinctions is critical in equine evaluation, especially in assessing physical health and dental care needs.