How to get the less deformation posible

We need to know which of the zortrax material has the less contraction of them all and what setting would reduce the deformation or contraction of the printed part.

I have been reading that layer height has an impact in the contraction of the printed part, we are open to all recommendations including room temperature controll, side covers(we have them), etc.

Best Regards!

http://support.zortrax.com/designing-and-post-processing/materials-functionality/

http://support.zortrax.com/home/designing-post-processing/design-for-3d-printing/

http://support.zortrax.com/home/zortrax-m200-overview/materials/

http://support.zortrax.com/designing-and-post-processing/materials-functionality/

http://support.zortrax.com/home/designing-post-processing/design-for-3d-printing/

http://support.zortrax.com/home/zortrax-m200-overview/materials/

I have seen some of this but doesn't really tell me if there is any difference in contraction between Z-GLASS, Z-HIPS and Z-PETG. Does anyone know which has less contraction?

I've seen this in the support center: 

  Setting proper dimensions

Different printing materials vary when it comes to their physical properties. The main thing you have to consider before the printing process is the level of shrinkage of a particular material. It can basically influence the actual size of a printed object which is usually smaller than the designed model. To avoid this, you have to estimate the approximate shrinkage and add a margin (usually from 0.2mm to 0.3mm) to each dimension.

Does this apply for all materials and geometries?

We are looking to print medical operation preparation models so we need to keep the dimensions as accurate as possible. But we want to do this with zortrax equipment.

Maybe the only way would be to print a model, scan it, compare to original model and correct deformation as much a possible the print again, scan again and compare again. still would be cheaper than using an objet printer.

I have found that Zultrat has the least amount of shrinkage. So when I need something exactly as it is designed, I use Zultrat. Otherwise I do an offset on hols of .2 to .3 so that when I print in Zabs the holes are just about right.

I hadn't done any extensive testing or measurements. Only what I have found that works for me. 

I'd advise PLA, but you'll need to mod your printer in order to use it (google it).  PLA has great strength and extremely low warp (shrinkage), its one drawback is that it could soften if used in hot conditions (think hot car in the sun). 

We have a PLA printer (Rep 2) but I found that the models tend to wrap a lot even more than Z-ABS (printing with covers). Having a biocompatible low wrap material would give zortrax a real good competitive edge, that would be great with soluble material on the Inventure,