Dental Dad Diary: Record Base & Occlusal Rims

Thursday, September 1, 2011

Record Base & Occlusal Rims

This post is a long time in the making since we started making our Record Base and Occlusal Rims almost a month ago. My last post from dentures was about making Custom Trays. Last Wednesday, we took our competency on making upper and lower custom trays - which, remember, are used to take the final impressions for dentures, or, to capture the last tooth in the arch for a prep (like in Fixed for our FGC on #15).

The Record Base and Occlusal Rims are the 'meat' of a complete denture. With these, we will try them in on a patient, a "wax try-in," to make sure the denture will be sitting correctly and aesthetically. Next, we will set teeth in the waxed Occlusal Rim, check the occlusion, adjust the teeth, etc until all the teeth look like they will in the complete denture. Lastly, we will cover everything in Vaseline, pour stone over the entire prosthesis (Vaseline to prevent the stone from adhering to the teeth), melt out all the wax and resin (now the teeth are just sitting perfectly in the stone), then pour molten acrylic in the stone shell to get the final denture. The stone and acrylic steps are done now-a-days in a lab. Only two or three years ago, all the dental students would do this step themselves, but since we got the new pre-clinical labs, they removed all the lab equipment required to do this step. Once we get our teeth set, we will send it to a lab and get the finished product back. At that point, we will finish and polish the completed denture! Comprende?

Yesterday we started setting teeth in the Occlusal Rims - well most of the class started setting teeth. Since we aren't doing this on a real patient, we use a patient articulator to take the facebow (with all the patient's measueremnts) and mount it on our articulator. My lab bench's patient, however, had to remount our mandibular model because someone screwed up our patients settings! Oh well, Looks like I will be spending another weekend in lab setting teeth.

If you have any advice on setting teeth, feel free to leave them in the comments section!

Below are some pictures from my process of making my record base and occlusal rims. Many of the pictures are just a snapshot of them as I perfect them. Enjoy!

Edentulous patient model. This is what we would get from making the
custom tray

Pink Triad before polymerization. Thin on the buccal and the ridge

After Polymerization.

Starting to make the occlusal rims. Too bulky, too high. . .

I have to reduce the hieght of the rim so that the top of it lines up with those
lines 1/2-2/3 up the retromolar pad

Much better!

The bulk of the work done. Now just little adjustments to make it look
perfect

Maybe a little too thin in the canine eminence

Tilted?

Looking pretty good for my "wax try-in"

Now I just need to take the facebow, mount
my maxillary, put it back on the pt articulator,
make huge notches in my mandibular
wax rim, take IU wax record, and mount my
mandibular.