A baby tooth normally stays in place until a permanent tooth comes up underneath it, pushes it out and takes its place.
Usually the front eight baby teeth fall out between six to eight years of age and the back twelve baby teeth fall out between nine to thirteen years of age. If a tooth is lost earlier than usual, the surrounding teeth can shift into the empty space and prevent the permanent tooth from erupting. To prevent future space loss and orthodontic problems, Dr. Mann may recommend a space maintainer.
A space maintainer will hold open the empty space left by a lost tooth. It will hold the remaining teeth in place and prevent movement until the permanent tooth erupts into its proper position. It is easier to keep the teeth their correct place now with a space maintainer, than to move them back into place with orthodontic treatment in the future.