By Nan Talleno

PHILADELPHIA (CBS) - Like humans, dogs and cats will have two sets of teeth in their lifetimes. All adult canines have 42 teeth. There are 12 incisors, 4 canine teeth, 16 premolars, and 10 molars; 20 teeth in the upper jaw and 22 in the lower.

Puppies have 28 baby teeth that erupt through the gums between three and six weeks of age. Puppies don’t have molars. They begin to grow their permanent adult teeth at about four to six months old. The molars come in last at about six or seven months of age.

You may find an occasional tooth here and there. But don’t be surprised if you don’t find many. Many animals do swallow them as part of the normal process.

Adult felines have 30 teeth. Kittens grow 26 baby teeth called “milk teeth” when they are about two to four weeks old. The milk teeth will later be replaced by the adult teeth by the time a kitten is six months old.

An adult cat also has four canine teeth, which are surrounded by very sensitive tissue. This was meant to allow the cat to feel exactly where to bite prey for survival purposes.