You had an accident and lost two of your front tooth. You look pretty different now. You need to do something about them. You go to your dentist. He takes some sample tissue from your current teeth and you leave. When you return sometime later, he implants newly grown embryonic tissue into the place of your missing teeth. She advices you on your new diet and you leave. A few weeks later you come back for check-up. He shows you the small teeth growing in your jaw. It is identical to what you had before, since it is derived from your own genes. The cells know which tooth they have to become by getting signals from their surrounding environment. Eventually, your teeth are fully grown and are like the original you had before the accident.
You feel confident about your looks and wonder what people did in the past when they lost their teeth. The thought of false teeth makes you shiver.