Imported object does not keep its size or proportions

I am trying to import a scan of an object and alter it using animation functions then output it to a printer or carver. I made a plaster model as a standard to compare my digital model to. I scanned the plaster and imported it into blender. It had severe sizing problems that were fixable by adjusting the unit scale, but it also had differences in the measurements in x and y axes that are not present in the plaster model. That proportional relationship has to be consistent. Thanks for any thoughts on what might be causing this problem.