Abstract: A system for repositioning teeth a patient from an initial tooth arrangement to a final tooth arrangement includes a plurality of incremental position adjustment appliances, each having an arrangement of cavities shaped to receive and reposition teeth of the patient. The cavities in at least one appliance in the system have a different geometry than that of at least one other appliance in the system. At least some of the appliances in the system are successively worn by the patient to exert force on at least one tooth and move the teeth of the patient from a first arrangement to a successive arrangement different from the first arrangement. The system includes a first multilayer shell with a bending stiffness factor less than about 0.1 GPa*mm3 and an elastic modulus no greater than about 1.5 GPa; and a second shell with a bending stiffness factor greater than 0.1 GPa*mm3.

Abstract: A planar display panel is described having an X-Y array of individually controllable display elements. A thin film floating gate transistor with memory capability is disposed integral with each display element. A storable information potential is applied to the transistor gate to induce a potential on the floating gate which determines high and low conductance states for the transistor. Preferred operating modes are set forth. A preferred physical layout for the display elements is provided in which the memory transistor is optimally located to provide the maximum display area.