Active band and loop refers to using a modified band and loop space maintainer to not only hold space for a permanent tooth but also to regain space that has already been lost”
Regaining space can be achieved with a Band and Loop Unilateral Space Maintainer featuring molar tubes and coil springs. This configuration provides continuous tension, allowing for the mesial movement of a premolar along with some reciprocal distal movement of the permanent molar. To adjust the appliance, stretch the coil springs before the initial seating. Typically, no further adjustments are needed. For easier insertion, it’s advisable to pre-assemble the activated appliance on the working model, and then use dental floss to keep the activated loop passive during cementation.