A dermal elevator is a device resembling a spatula which is used to create a pocket for implants.
In order to place an implant under the skin, an incision is made, and then a "spatula" type device is used to lift the tissue and form a pocket in which to place the implant. Elevators come in many shapes, sizes, and sharpnesses, but to generalize, they look sort of like medical versions of a butterknife.
Elevators are not the only tool used to create pockets—some doctors and practitioners prefer to use blunt medical scissors and similar tools. They are inserted into the incision while closed, and are then opened, increasing the size of the pocket.