getting ready to start my 17th set of trays! My bottom teeth are now complete, so each bottom tray from this point forward will be exactly the same. I have 17 more trays to complete the top teeth. I am 56 year old male and will be pretty happy when this is all over....lol. After that I will be married to the nighttime retainer. Also, my dentist offers a chain that he bonds behind the lower front teeth which keeps them from ever moving. He actually has one in his own teeth.