Puppies have a full set of 28 milk teeth – 4 canines, 12 incisors and 12 molars. The incisors and canines grow in first, the molars last. At around three to four months of age, your dog is going to start losing milk teeth and growing in her adult set of teeth, which consists of a total of 42 teeth – a lot more than the puppy teeth she has. The first to fall out are going to be her incisors, her front teeth. She will start growing her adult incisors first. Around four to five months of age you will see her adult molars and canines to grow in. By about six months, she should have her full set of adult teeth.