A device, for atraumatically elevating the Schneiderian membrane during a sinus lift procedure with positive, real-time indication of the amount of lift occurring, may include: a first conduit; a first balloon coupled to a first end of the first conduit and in fluid communication therewith; a second conduit; a second balloon coupled to a first end of the second conduit and in fluid communication therewith; and means for infusing a fluid into the first and second conduits to cause inflation of the balloons. The balloons may be constructed the same, or may be individually tailored. The first balloon is configured to be received within the implant socket and apply pressure to the membrane. The second balloon, expanding against atmospheric pressure only, is configured of a different material and wall thickness. An integral scale behind the second balloon provides indication of the inflation and lift provided by the first balloon.