There are 2 stages of teeth growing in our life as a normal human.
According to Human Teeth Dental Chart from bradfordfamilydentist.ca, once we were borned till about 6 months of age, we have our first teeth. We called our first teech as deciduous teeth. They might also be known as baby teeth, milk teeth, or primary teeth in the dictionary. All 20 deciduous teeth will be fully grown into your mouth at the age of about two and a half years. The teeth will then started to lose from 6 until 12 years of our age.
Later, they are replaced by permanent teeth which is also called adult teeth. There are 32 permanent teeth that you will need to take care of them until the end of your life. All the 32 adult teeth started to growing through your gums from your 6 years age and all will be finished growing into your mouth by as you reach 18 to 25 years old.