Only a modest change in molar relationship can be produced by this combination of differential growth of the jaws and differential forward movement of the lower molar. It must be kept in mind that the changes described here are those that happen to a child experiencing a normal growth pattern.  The transition in molar relationship from the mixed to the early permanent dentition are summarized. Note that the transition is usually accompanied by a one-half cusp (3 to 4 mm) relative forward movement of the lower molar, accomplished by a combination of differential growth and tooth movement. A child's initial distal step relationship may change during the transition to an end-to-end (one-half cusp Class II) relationship in the permanent dentition but is not likely to be corrected all the way to Class I.