Unlike conventional dentures, immediate dentures are made in advance and can be positioned as soon as the teeth are removed. As a result, the wearer does not have to be without teeth during the healing period. However, bones and gums shrink over time, especially during the healing period following tooth removal. Therefore a disadvantage of immediate dentures compared with conventional dentures is that they require more adjustments to fit properly during the healing process and generally should only be considered a temporary solution until conventional dentures can be made.
An overdenture is a removable dental prosthesis that covers and rests on one or more remaining tooth roots. A removable partial denture is a dental prosthesis that replaces some teeth and is built around existing natural teeth. Both the overdenture and the removable partial denture may be connected to the remaining tooth roots or remaining natural teeth with anchors made of metal or plastic. These connections improve stability and the retention of both prostheses.