Dear Daisy Dog: Oscar, our Yorkshire terrier puppy, seems to be growing a second set of some of his front teeth, including his fangs. Is this a problem?

Daisy Responds: Yes. Oscar’s mouth has room for only one set of teeth, so any additional teeth can cause problems as he matures.

It sounds like Oscar may have a condition called retained deciduous teeth, which occurs when the baby teeth don’t fall out but persist where the permanent adult teeth should sit. The canine teeth (fangs) are most frequently affected, but any deciduous tooth can be retained.

The disorder is very common, especially in toy breeds and other small dogs.

When a deciduous tooth remains in place, the corresponding permanent adult tooth is forced to erupt in an abnormal position, usually to the inside of the deciduous tooth. The exception is the adult canine tooth, which erupts closer to the incisors, the front-most teeth.

Retained deciduous teeth are usually extracted. It’s best to have this done as early as possible, so make an appointment with your veterinarian now.

Without treatment, the gums around the crowded teeth trap food and become infected. In addition, the gums and other supporting structures do not fully attach to the adult teeth, so they’re less securely anchored in place.

Your vet may refer Oscar to a veterinary dentist, or you can find one through the American Veterinary Dental College (www.avdc.org) or the Academy of Veterinary Dentistry (www.avdonline.org).

February is National Pet Dental Health Month, a good time for others to follow your lead and check their pets’ mouths for abnormal dentition, bad breath, inflamed gums and fractured teeth.