Initial CureGel Tests.pdf (851.2 KB)
Please see the attached PDF file for accompanying photos and notes.
Initial Results: I printed three occlusal splints with Dental LC on the Form2, each with different orientations (internal testing you can call it). After washing/drying all three splints the exact same way, I used CureGel on only one of the three splints for post curing. The splint that I decided to use the CureGel on, was printed in the absolute least favorable orientation. FormLabs recommends printing splints "oriented at an angle of 30° or less, measured relative to the build platform. Orienting parts upright or at angles more than 30° will compromise precision and lead to poorly fitting parts."
The splint that received the CureGel was printed in a near vertical orientation, which technically should lead to "poorly fitting parts." The reason I picked this splint for the CureGel testing was mainly because I was planning on using one of the other two, printed in the recommended orientations, to actually deliver to a patient. So my thought was, no matter what this CureGel does, at least it will be on a splint would not "go into production."
I took pictures of each splint, during each step, along the way - mainly to document the appearance (even though I now realize the CureGel is not intended to add any aesthetic value). I am not a professional photographer, or even a good photographer, so I realize some of my interpretations of the photos may just be lighting/glare issues. The main point is that I feel there is a noticeable appearance difference, not necessarily in an aesthetic way, but in a way that showcases the completion, and level of detail of the cure. The splint with the CureGel, in my opinion, was much more uniform in color, shade and texture. Again in my opinion, this would indicate a more ideal completed cure, which is vital when using biocompatible resins due to the possibility of residual unused monomer leaching.
After removing the support structures and the bases (none of which had supports touching the intaglio of the splints - a.k.a. the part of the splint that interfaces with the teeth, and determines the quality of fit), I tried on each splint to the original patient stone model. Ironically, and to my complete surprise, the splint treated with CureGel was literally a perfect fit, despite it's adverse printing orientation. Again, suprisingly, the two splints printed in the correct orientation, but not treated with CureGel, did not fit on initial placement. I'm sure it's possible to adjust the intaglio on the ill-fitting splints, and get them to fit normally, but I have a suspicion it is all related to the curing process.
My initial opinion, is that the CureGel is well suited to get into the nooks and crannies of the intaglio of the splint, which provides a more thorough and proper cure to those areas. It seems as if, it is precisely these areas that residual resin can be left behind, even after rinsing and drying, and when that minimal residual resin cures without the CureGel in place, it simply is cured on top of the actual defined dimensions of the splint. This therefore, can lead to ill-fitting splints that require further adjustment in order to fit, or they may not fit at all.
I realize there a lot of confounding variables in this little initial experiment, but you gotta start somewhere. Of course I will continue to test my theory, but if curing with CureGel leads to more accurately fitting parts, than it would be a no brainer to me, and every other dentist in the world, to add this to our 3D printing toolkit.