Controlled slicing in the management of congenitally missing second premolars.

This report describes a simple method of allowing permanent first molars to drift mesially in patients with congenitally missing second premolars, thus facilitating future orthodontic treatment. Controlled slicing of the deciduous second molar between the ages of 8 and 9 years produced a bodily controlled mesial movement of the permanent first molar in less than 1 year with no or minor rotations or inclination. These results are compared with controlled slicing in 10- to 11-year-olds and with treatment involving extraction alone.