I actually really enjoy doing dentures.
Part of the reason is I had terrific mentors that instilled their passion in me for the art of removable prosthodontics. Two people to check out are Vincent Verderosa CDT, MDT and Joseph Massad DDS.
Dr. Massad has published numerous articles on his tips for impressing complete dentures with polyvinyl siloxane. If you’d like to learn more, check out his articles in Dental Ecomonics and other journals. What follows is my technique adapted from some of his wisdom.
As for material, I’ve been happy with Aquasil by Denstsply. I use Aquasil Ultra Heavy Fast Set for the heavy body and Aquasil Ultra LV Fast Set for the wash.
So here’s a maxillary CD case. Upper custom tray is ready to go.
First I use the heavy body in four spots to create rest stops.
Impression 1: Rest Stops
Next I use the heavy body again to border mold. I like to let the material sit for about 30 seconds so that it’s more firm. I place it in the mouth and go through the border molding process.
Impression 2: Border Mold
There we go. Now I check the borders to make sure they are all covered with sculpted impression material.
Aha! What do we have here?!?
Oops...
Well, that’s okay. One of two things happened: the impression material got rubbed away or the custom tray was over-extended in that area. Either way, I take an acrylic bur and relieve the tray in that area.
Relieve the Tray in Areas Where the Borders Are Not Molded with Impression Material
Now we’re ready for the wash with medium body PVS. Some people will cut small holes through the tray to allow the excess material to escape. Personally, I don’t do that; I just try to dispense the correct amount of material. Et Voila!
Impression 3: Wash
This technique works for removable partial dentures as well. However it is important to ensure that you can re-seat the tray over the teeth in between each impression.
For a full discussion of using this technique when teeth are present, check out this post here.