What can they put between your tooth after they pull the baby tooth?

Space maintainer. : I am assuming that you are asking what is placed between teeth after a baby tooth is pulled. On children, we like to place a spacer or space maintainer to hold the space open for the permanent tooth to erupt to reduce crowding or misalignment. On adults with residual baby teeth, we would place an implant to replace missing tooth, stabilize arch, and preserve bone. Your dentist can discuss these.

Space maintainer: If a baby tooth is lost prematurely, a space maintainer is essential to prevent collapse of adjacent and opposing teeth into the space. It is important that this be coupled with 1st orthodontic examination (usually complimentary) @ age 7. Better to be seen too early than to hear, "oops, should have been here months ago because...".