Can you guide me about taking impression with impression compound?

[Dr Pepe]

Hello everyone,
I am bit confused regarding impression taking in Prosthodontics. It is the most basic step and the success of a denture surely relies on it.
While taking the impression with the impression compund, I don't apply pressure in the rugae area but I do apply pressure in the posterior palatal area and the ridges. Along with this, I move the cheeks in "C"pattern to perform border moulding. And at the anterior area , I move the lip outward a bit to record it.
Is this the right way to do it ? They say impression compund is mucostatic , so should I be applying pressure? Please guide me.
I have checked with a number of sources and the opinions very from one source to the other.
Thank you~~

 

[MattKW]

Sorry, haven't used compound for 30 years.

 

[Dr Pepe]

Sorry, haven't used compound for 30 years.

If not impression compund then what do you use for taking impression in case of complete denture ( completely edentulous patient)?

 

[honestdoc]

Where are you located? Here in the US, we use vinylpolysiloxane (VPS) impression material on preferably a custom tray. In my high volume state funded practice, I use alginate preliminary impressions on stock trays, establish a wax rim bite record, and later a wax teeth try-in. I use the waxed teeth as my custom tray and before processing, I apply medium body VPS on the tray (waxed teeth) and have the patient ease down to the correct occlusion for about 5 minutes. Afterwards I verify the bite and the retention of the teeth. I work on a lot of malformed, mentally challenged and physically disabled patients and I find this as the simplest yet most predictable approach. A few times at another practice, I worked with a denture technician and completed a start to finish dentures in the same day.

 

[Sonia Salamuri]

I think the process described by Honestdoc is what I have seen at school. First alginate, and then wax for bite register. Also the same material, the vinyl polysiloxane is used for bite register and for impressions to be used on the prosthesis too, but with different viscosity. I would like to understand what is the material you are referring to.

 

[honestdoc]

We have 3 viscosities of VPS. Light, medium, and heavy. I use light viscosity for crown preps margins under heavy viscosity in impression tray. I use medium viscosity for dentures. When I was in Dental School in the mid 1990's, we had many appointments to fabricate dentures. We first did preliminary impressions with alginate. We poured the models and made custom trays. Second appointment we used dental compound, warm it and place it on the custom tray to "border mold." Afterwards we placed tray adhesive and take a final impression by hand mixing condensation reaction silicone. We also take a face bow transfer to mount the models. Third appointment we did a wax bite. Fourth appointment wax teeth try-in. Fifth is delivery and subsequent followup visits and adjustments. Unfortunately, these steps are so long and inefficient for real world practice and I summarized my steps in my previous post.