An overdenture is a type of removable denture that is used for people who still have a few remaining natural teeth or on implants. The overdenture is made to fit over the teeth roots left in the bone; it uses the teeth roots (with nerves removed by root canal treatment) as an anchoring support for the denture. Usually, dentists like to keep as many natural teeth as possible, even when a complete denture is needed. To be kept, natural teeth must be shaped to fit under the overdenture and usually undergo root canal treatment during which the nerve of the tooth is removed so they’re not too sensitive to the shaping process. The teeth are then usually covered with metal castings or porcelain that fit into the overdenture or implants that snap into place.