Adult dogs have 21 teeth in each jaw for a total of 42 teeth. Puppies have 14 teeth in each jaw and 28 total teeth until they shed their milk teeth for adult dentition.
Puppies begin to achieve adult dentition at an age of 3 weeks. The main difference between the dental formula of puppies and fully grown dogs is that puppies lack molars. Molars are the most rearward teeth with large, ridged grinding surfaces for gnawing. Premolars, which puppies do have, are smaller than molars. The premolars are the transitional teeth between the cone-shaped, tearing canines and the multiple-ridged, gnawing molars.