Baby teeth, particularly the molars, guide and hold the space for the permanent teeth to erupt in the proper position. When the baby molars are lost early due to extraction (particularly before age 8), a space maintainer may be recommended to prevent the other back teeth from shifting around and blocking the permanent teeth from having room to come in all the way. A space maintainer is a metal appliance with a band that is cemented to the tooth behind where the space exists, with a metal loop attached to it that touches the tooth in front of the space. The space maintainers are intended to remain in place until the permanent tooth is ready to come in, which can be a few years depending on the age of your child. It is important to maintain good oral hygiene to prevent decay around the appliance and avoid eating very sticky/tacky candies which can pull the space maintainer off. Regular appointments to the dentist are important to verify the cement is sealing the appliance well and determine the appropriate time to remove the space maintainer. If the space maintainer feels loose or comes off, it is important to call the dentist as soon as possible to have the spacer evaluated and re-cemented. If the space maintainer comes off completely, it is recommended to leave it off and store it in a safe place until you can bring it to the dentist to have it re-cemented as soon as possible.