https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=dental%20resin%20shrinkage

Just clarify, because your question implies that both polymerisation and water sorption induce shrinkage: polymerisation causes shrinkage of ~2–6 vol% and then water sorption subsequently causes expansion of ~0.5–1%, thereby partially cancelling out some of the shrinkage.

Shrinkage can be minimised by:

- increasing filler content to the maximum possible (to the wet-point limit)

- in the case of dimethacrylates, selecting high molecular mass monomers (e.g. Bis-GMA, Bis-EMA, UDMA) rather than smaller molecules (e.g. TEGDMA)

- using silorane monomers instead of dimethacrylates

With regards to the first two points, there will be a trade-off between increasing the content of large molecules and increasing the filler content, due to the increase in viscosity that both cause.

There are plenty of reviews available on this topic the chart the progress in reducing shrinkage, but I would say that only negligible improvements will be made in the future beyond the current low-shrinkage systems.

An alternative approach is to induce just the right amount of water sorption to counter the shrinkage. The incorporation of calcium phosphates in dental and orthopaedic composites results in increased water sorption and this can be carefully optimised to counter polymerisation shrinkage. It is important that water sorption does not exceed shrinkage, as this can result in tooth fracturing, as was initially the case with compomers.

http://link.springer.com/article/10.1007/s11043-012-9190-0.

Mechanics of Time-Dependent Materials

February 2013, Volume 17, Issue 1, pp 1-13

This is the only paper that deals with 3D calculation of shrinkage stresses in dental restorative materials. Probably, it will be of some help at least from the point of view of viscoelastic  phenomena complexity that emerge when reacting,  highly confined, system are under concern. 

Clear answer:

principally, polymerization without shrinkage is nearly impossible.

Only some exceptions:

. Ring opening polymerization of small rings leads to reduced shrinkage

. starting from ordered structured monomers to end up with amorphous polymers

. reduced concentration of vinyl groups (large monomers, fillers)