If your dog's bottom jaw is significantly shorter than the top jaw, he may be suffering from an overbite. Also known as prognathism, the bite can interfere with a dog's ability to grasp and chew and can result in misaligned teeth that strike each other, leading to wear or breakage.
What It Is
In most breeds, normal jaw alignment is known as a scissors bite, with the incisors fitting neatly side by side when the mouth is closed. With an overbite, the lower incisors are situated closer to the head than the upper incisors, leaving a gap between them when the mouth closes. If you can fit the head of a wooden match into the space, consult your veterinarian to see if treatment is necessary.
Your veterinarian will be able to tell if your dog's overbite requires treatment or if the gap will correct itself as he grows. The exact course of treatment depends upon the cause of the overbite. Orthodontics such as tooth spacers or special crowns may be necessary, or a displaced tooth causing the jaw misalignment may need to be removed. The condition is usually hereditary, and you should not breed a dog with a serious overbite.