backwards relative to the orientation of stumps 61 and 63 additionally user 10 may specify dental cad cam system 10 to merely eliminate areas protruding from the blank volume with various parameters modified user 10 may again orient the stump within the blank volume 47 and continue to loop in this manner until satisfied however if user 10 determines it is no longer helpful to modify parameters 41 a user 10 may determine the blank volume is simply of dimensions incompatible with the expected dimensions of the dental restoration 42 a if user 10 is however able to successfully orient stump landscape within blank volume user 10 may proceed with the restoration design 49 thus leaving functionality contained within blank size confirmation module 8 the process described with respect to fig4 has been described as being invoked before any substantive design of the eventual dental restoration has been completed but this is for exemplary purposes only blank size confirmation module 8 may be similarly invoked at any stage during the design process if invoked later substantially the same process as shown in fig4 could be used but the initial stump landscape would be the current state of the dental restoration rather than the scanned stump or stumps and all layers applied to the stump 46 would be explicitly defined by user 10 in the embodiment described with respect to fig4 a layer equal in thickness to the minimum thickness of a.