Quick Answer. An experimental variable is something that a scientist changes during the course of an experiment. It is distinguished from a controlled variable, which could theoretically change, but the scientists keep constant. Continue Reading.
While you were pregnant, your baby developed tooth buds, the foundation for baby teeth (also called milk teeth). Very rarely, a baby is born with a tooth or two, or grows a tooth in the first few weeks of life. But the vast majority of babies sprout their first tooth sometime between 4 and 7 months old.
They are just baby teeth, why fix them? Most babies get their first tooth around 6 or 7 months of age; usually the bottom front two incisors. Some kids are a little slower erupting the first tooth causing parental worry. It can be even around 12 months for the first one to poke through. Additional baby teeth will continue to come in till almost three years of age. There really is a lot of variability on the sequence.