PVS Complete Denture Impressions: The Massad Technique

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.

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38 Comments

  1. william fell says:

    where do you get trays?–thanks for info

    • Chris says:

      I start with a preliminary alginate impression using stock trays. I’ll then have my dental lab fabricate custom trays for the final impression. These custom trays are made from Triad Custom Tray Material. You can make these yourself if you have a curing chamber in your office.

  2. lucas says:

    Thanks for the information on your website. I am currently in dental school and the material you post has cleared alot of things up for me. Can this Massad impression technique be used in making impressions for night guards? Thanks.

    • Chris says:

      I’m glad you’ve found the information useful, Lucas! Yes, you can use this impression technique to make study models to fabricate any prosthesis or appliance. However the strength of this technique is that it predictably reproduces the information you need for complete and partial dentures (mucco-buccal fold, muscle attachments, etc.)
      If you’re fabricating a night guard, you really just need to capture the teeth, not all those soft tissue details. I just take an alginate impression for that. It’s faster, less expensive, and works great. Hope that helps!

  3. Pingback: PVS Denture Impressions With Teeth Present | The Curious Dentist

  4. Greg Bauman says:

    After relieving the overextended custom tray do you re-border mold with heavy body in that area or do you just go straight to the wash impression?

    • Chris says:

      Great question, Greg. I’ve done it both ways and both have worked. My feeling is that small overextended areas of the tray can be corrected in the wash with confidence. But if the overextended areas are larger, longer, or too numerous, it’s better to re-border mold with heavy body.

      • H says:

        Why do you have to border mold with heavy? Will you not capture the borders with your wash?

        • Chris says:

          Thanks for the question. I use a heavy body because I want to have some resistance to the border moulding procedure. Pulling and tugging on the lips and cheeks will shape the impression material at the border. A more “runny” light body material can have too much give.

  5. DRDILIP says:

    NOW WITH THAT TRAY HOW DOES THE TECHNIQUE REMAINS A SELECTIVE PRESSURE IMPRESSION TECHNIK?

    • Chris says:

      If I understand your question correctly, you’re asking how this technique avoids putting too much or too little pressure while taking the impression. The right amount of pressure is applied because the first step is to make tray stops with the heavy body material. This will allow you more control in placing the correct amount of pressure since you have more tactile feel than if the tray was full of impression material. Once you get to steps 2 and 3, you can seat the tray all the way down with confidence knowing it will be stopped by the rest stops.

  6. Sam says:

    Do you paint an adhesive on your tray? Thanks

    • Chris says:

      I do paint adhesive for custom tray impressions. There aren’t any holes or slots in the custom tray, so adhesive is a must to ensure that the impression will be retained in the tray. If you did have multiple holes or slots in the tray, the PVS impression material would run all over the place.

  7. Spence Bloom says:

    I like your discussions of clinical dentistry…
    Comments: 1- mid palatal stop is superfluous (unless ridges are flabby)
    2-all 4 stops shown could be trimmed to 1/2 that size. 3-Massad emphasizes that final impression layer can be multi-viscosity to enable least pressure on flabbiest areas 4-one function of holes in tray is material retention (vps adhesive is not super retentive); another function of holes in tray is as pressure relief where tissues are flabby.

  8. H says:

    Can you use medium body for denture imp? I don’t seem to get that suction after removing the imp. Why?

    • Chris says:

      I use medium body for the wash impression, yes. A lack of suction is probably due to the borders not being sealed. Make sure you have adequately sealed the borders with a heavy body material. I often find that I have some suction even after border molding (before the wash).

      • H says:

        If you don’t have the suction on your wax rim plate, does that mean the denture will be loose? Do I need to border mold and take imp again using the acrylic rim?

        • Chris says:

          I usually have a little bit of suction with the wax rim plate, but it’s not essential. I trace the border of the hard and soft palate with a Thompson’s marking stick and transfer that to the wax rim plate. The lab technician will carve our some stone in this area so that there will be a strategic addition of acrylic for better suction. This technique goes by a few names, including “marking the post dam seal.”
          The technician will flow wax (which will become acrylic) into all the nooks and crannies of the final cast, which hopefully was border molded well.

  9. Dr. Prashant Jadhav says:

    Thank you for this useful information sir. Can you give me any reference article for this technique?

  10. saadia says:

    Hi, very informative article. Currently I am volunteering in a third world country where they do not have heavy body in guns instead they use Putty (base/catalyst) which is hand mixed and regular or light body for everything. My question to you is how do I use this technique with putty for borderr moulding and initial stops. Your input would really help

    • Chris says:

      Hello Saadia,
      Thank you for your amazing volunteering efforts! It is so important that good people like you in our profession donate our services to those less fortunate.
      I am familiar with the putty heavy body but I have not used it with this impression technique. I think it would work the same but these two differences: (1) the putty is initially more firm that heavy body from a cartridge, so that will help it adapt more accurately during moulding, however (2) the putty will probably require some sort of adhesive to help keep it attached to the tray.
      So I would use the putty first for initial stops, then for border moulding, then I’d use the light body as a wash. Please let me know if this is successful!

      • H says:

        I too have putty to use but have yet to use it for a denture final impression. Is it possible to use the puty as the tray itself? I think ive seen that done once at a VA. How can u border mold with putty? Isn’t it less viscous than the one in the gun thus making it difficult to mold?

        • Chris says:

          That’s an interesting point. I suppose putty could work but there’s probably a reason why it’s not normally used. I think the lower viscosity would make it less desirable for the details that we’re looking to capture. If you try it, let me know what you think!

  11. Sean says:

    Great website Chris! can’t remember how I stumbled across it, but have been reading lots of your posts now! Very good stuff here…

    How much space do you like to have between the tray and the muco-buccal fold prior to border molding with heavy body?

    • Chris says:

      Thanks, Sean! If you leave too much room, there will be lots of heavy body material and it may flop around. If you leave too little room, you’ll have a lot of areas where the tray shows through. So I try to leave just a couple of millimeters between the tray and the muco-buccal fold. This goes by “feel” more than anything else.

  12. It was a great discussion forum , it has answered most of my Qs about F/F impression techniques for a predictably successful set of Dentures. Thanks Chriss & everybody who contributed on this page. Regards!!

  13. H says:

    I was wondering, d you border mold with green stick compound before you place the tissue stops and border mold with heavy body and and move on to the wash. I am a new dentist and would like to hear about the green stick, Great website and information exchange.
    thank you,
    h

    • Chris says:

      Tissue stops are always my first step. That way I know I will have room for the border molding and wash material. I enjoy doing this procedure entirely with PVS impression material so that I don’t have to use green stick compound at all. I can make the compound work successfully, but it gets messy and is tricky to use. Good luck!

  14. ilya says:

    I was wondering can you order the custom tray with premade tissue stops?

    • Chris says:

      Yes! If you are fabricating a custom tray or are ordering one from a lab you can ask for them to build in rest stops with Triad material.

  15. Albert says:

    What are your thoughts on using the wax try-in as the special impression tray and doing the final impression in this wax try-in with a light body pvs

    • Chris says:

      Thanks for the question, Albert. That technique would save the bite rim visit, however the dentist would have to feel comfortable moving the teeth around quite a bit. I would think there is a good chance for the maxilo-mandibular relations (MMR), vertical dimension of occlusion (VDO), and esthetic set up to be a bit off if the bite rim visit has been skipped.

      • Albert says:

        Sorry! Didn’t explain myself properly.I don’t skip the wax bite registration. The final pvs impression(light body Virtual) is taken in the wax denture set-up.

  16. kurien says:

    sir regarding selective impression technique u want to give pressure to the primary stress bearing area such as inclines of hard palate and less pressure to the relief areas such as mid palatine raphe and u are placing the stops on the rugae palate and posterolaterl areas can u explain that

    • Chris says:

      Thank you for the questions. I do not apply selective pressure because I think that would be difficult to control. Personally, I place the stops in somewhat random areas, spread out around the tray. I do not consider placing them in primary or secondary loading areas, although that might be an interesting technique to study. I’m not sure if that makes a clinical difference.

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