Well I'm 10 and I have lost 19/20 teeth. Once I was at the dentist and he oticed something strange with one of my molars. He took an x-ray and phoned us the next day and said that my left,bottom molar at the back was submerged (it had not grown up high enough for me to loose it yet so it's taking its time!) anyway it will probably take ages to come out and it is my last one! SOO ANNOYING!