My daughther was born without enamel on her back molars. I didn't realize this until I took her to the dentist when she was 2 years. There was a cavity found, the dentist filled the cavity and sealed her teeth. It was very simple, wierd, but simple. The dentist told me not to worry about it and that her adult teeth would be fine and have plenty of enamel. She is 9 now and the dentist was right! Don't worry, as long as you can seal the teeth, your baby will do fine.