My son started getting brown stains on his teeth at about age 2. The pediatric dentist stated it was iron stains (my son does not take any iron suppliments) and polished most of the stains off. One to two months later the stains returned and have gotten worse. I have another appt. with the same pediatric dentist but cannot understand why the stains return so quickly. He has a normal and healthy diet, teeth brushed twice daily, and has not used bottles since he turned one. He still uses a pacifier and likes to put almost everything in his mouth (ie. Keys on key ring, Thomas the trains stuff) despite continued efforts to get him to stop. Any suggestions would be helpful.