A system and method for synchronously processing ear shells for hearing aids comprising: loading data associated with a first and second ear shell; determining whether to perform a rigid or non-rigid registration of the data associated with the first and second ear shells, wherein the rigid registration is performed when shapes of the first and second ear shells are within a predetermined threshold, and the non-rigid registration is performed when the shapes of the first and second ear shells are not within the predetermined threshold; registering the data associated with the first and second ear shells; processing the first and second ear shells, wherein the processing is synchronously performed; and outputting the processed first and second ear shells to a display device.