Complete dentures are plates of artificial teeth intended to replace all of the natural teeth in the upper or lower jaw. The plate is made out of gum colored acrylic and it sits on the tissue of the mouth that covers the bone ridge. A partial denture is a removable appliance that replaces multiple missing teeth, but fits around the remaining natural teeth. This type of denture uses both the soft tissue ridge and the remaining natural teeth to secure it in place. Partial dentures can be attached to the natural teeth using clasps or attached using crowns with hidden clasps. Dentures are necessary to keep facial muscles and lips from sagging, and to allow the patient to speak and eat normally.