The purpose in using resin-modified glass ionomers (RMGI's) with ART is to stabilize the child and the lesion(s). While sometimes the lesions may be quite large, they still can usually be stabilized.

The RMGI restorations often may be interim in nature, lasting until more durable restorations can be placed at a time when the child's behavior can be better managed. In fact, the basic idea is to provide a therapy that may last only several months, but still last long enough so that the child gains the maturity to be treated conventionally at a later time. Sometimes, retreatment is needed, and occasionally the RGMI restorations last for the life of the primary teeth involved.

This photograph displays a case of ECC that would require more than what a fluoride varnish could offer. Notice that the surface of the lesion is cavitated. You'll recall that fluoride varnishes are most effective when used on early white spot lesions which have an intact surface layer. Once obvious cavitation has occurred (which is what is seen in this photo), it is more appropriate to place a restoration, in this case an RMGI.