Like humans, dogs and cats start with baby teeth that get replaced by permanent teeth as the animals grow. In some cases, an animal gains a permanent tooth without losing the baby tooth first, resulting in what veterinarians call a "retained deciduous tooth." Usually, a vet removes any retained baby teeth when he or she spays or neuters a pet to avoid future dental problems.
Baby Teeth Versus Permanent Teeth
Baby teeth are also known as primary, puppy, deciduous, or milk teeth. Both dogs and cats are born without any teeth. By 3 to 4 weeks the baby teeth erupt. By 6 to 7 months of age, the adult teeth set beneath the baby teeth push the baby set out. Adult dogs have 42 permanent teeth, and cats have 30 permanent teeth.
The upper canine teeth or "fangs" (called canines in both dogs and cats) are the most common teeth that are retained. The next most common teeth are the lower canine teeth and the incisors. However, in some cases, the premolar teeth may also be retained.
If the retained tooth is a lower canine, the permanent lower canine is forced to grow on the inside of the lower jaw and its tip usually grows toward the roof of the mouth, causing pain when your pet eats.
The retained baby teeth are not as large or as hard (mineralized) as the adult teeth and risk being broken during play or chewing, which can lead to pain or infection at the site.
Signs of a Retained Tooth
A number of unpleasant external signs might give you a clue that your dog has a retained baby tooth like abnormally positioned teeth distorting the bite, crowding the gums, or causing bleeding gums. Gingivitis or gum disease may result from the teeth overcrowding and may also cause bad breath. Overcrowding or retained baby teeth can trap food and debris and lead to weakened teeth, tooth decay, or loss.
Much like human babies, who have a penchant for putting everything in their mouth, you may notice your puppy will have a strong urge to chew—just about anything. Allow your pet to chew acceptable objects. This aids in the teething process and reducing the chance of retained baby teeth.
More often than not, your pet's teeth will fall out while eating and your pet may not even notice the loss of the tooth. Most dogs and cats unknowingly swallow their baby teeth.
Also, like babies who are teething, you may notice your puppy drooling a lot during teething, getting irritable easily, and skipping a meal or two due to a tender mouth.
To Pull or Not to Pull
In short, baby teeth that do not fall out on their own by 7 months should be pulled. However, this is not something you should try on your own. Extraction of the retained tooth will require general anesthesia.
Most vets check for retained teeth at the time of spaying or neutering and remove any additional teeth for a small fee (or free, in some cases) while they have your pet under anesthesia. If you do not have plans to spay or neuter your pet, see your veterinarian to discuss removal of any retained teeth before dental problems occur.
If you wait too long to get the baby tooth pulled, the overall bite problems or jaw problems may require pricey pet orthodontic treatment to reposition the teeth.
Retained deciduous teeth are more common in dogs than in cats. It often affects smaller breeds of dog, including Maltese, poodles, Yorkshire terriers, and Pomeranians. Also, there is a higher incidence in dogs that have pushed-in faces such as bulldogs, pugs, Boston terriers, and boxers. Your furry friend may be more likely to have this condition if your pet's mother or father had the condition.