When I see a puppy for their first post adoption visit, the family often asks me to determine the pup’s age. Since weight and size are dependent on nutrition, I use teeth instead. Here are the guidelines I use for determining age in puppies: Please note that baby teeth are also called deciduous teeth.
2-3 weeks – no teeth are present. The gums feel smooth and hard.
3-5 weeks – deciduous canine teeth are present. Canine teeth are the large ‘fangs’ on the upper and lower jaws.
4-6 weeks – deciduous incisors are present. The incisors are the small teeth on the front of the upper and lower jaw located between the canine teeth.
5-6 weeks – deciduous premolars are present. The premolars are the teeth behind the canine teeth, toward the back of the mouth on the upper and lower jaw. Puppies do not have deciduous molars.
8 weeks – all deciduous teeth are present.
3-4 months– permanent incisors are present. I sometimes notice swelling of the gums in the area of the deciduous premolar teeth toward the back of the mouth. This swelling is caused by growth of the permanent premolars and molars under the gums.
3-4 months– at 3 months the area in front of the deciduous canine teeth swell. In my experience, the tip of the canine usually pops through the gum at 4 months and is fully in place at 5 months of age.
4-5 months – permanent premolars erupt. I find chilling the pup’s chew toys helps them get through this phase of teething.
4-6 months – permanent molars erupt. When these teeth are erupting, the pup will push toys into the back of their mouths and chew.
7 months – all permanent teeth should be present.
Please note, these are approximate times for eruption of teeth. Toy breeds often experience delays in eruption as well as retention of the deciduous teeth.
Source: -Gorrel, Cecilia. Veterinary Dentistry for the General Practitioner. Saunders 2004, p 30.