Disqualifications: Undershot bites; overshot bites exceeding 1/8 inches.

The Australian Shepherd should have forty two (42) strong, functional teeth that meet in a scissors bite.
In a scissors bite, the lower incisors should close immediately behind the upper incisors.
 A scissors bite is ideal for the Australian Shepherd  because it creates the least amount of wear, offers the most support and allows for a proper pinching grip of livestock .

An even bite is acceptable as it is still functional, but is faulted because it offers less structural support and the incisors are subject to greater wear.

The alignment of teeth is best determined by looking at relationship between the canine and molars as well as that of the incisors. In a true scissors bite the lower canines should lie exactly between the upper outside incisors and upper canines, yet touching neither. Pre-molar crown tips should meet in a saw-tooth manner, with the tips of the lower pre-molars pointing to a space between the upper pre-molars.

A prudent judge will check all areas of the bite, not just the relationship of the incisors when determining alignment.

This is an active, working breed and teeth are subject to breakage. A dog presenting teeth broken or missing by accident should never be penalized. These should be differentiated from genetically missing teeth.

The majority of genetically missing teeth in the Australian Shepherd will be the pre-molars, although the occasional molar or incisor may be missing. Genetically missing teeth weaken the overall jaw structure and leave the mouth subject to injury. The more missing teeth, the weaker the entire jaw structure will be. The Australian Shepherd ideally has full dentition. Genetically missing teeth should be penalized in accordance to the number missing..