in dental products

magic impression goo

Let me start by saying I am not on the payroll of any dental company. It’s not like I object to it or anything. I’m sure that I could be bought. Probably cheaply. But I’ve never been paid for my opinion. Yet I still feel compelled to talk about this new stuff I’m using.

I’m a bread and butter dentist. Lots of fillings and crowns, some root canals and extractions and a few implants here and there. So we take lots of impressions. Over the years I’ve come to hate packing cord. It was a necessary evil to get a good impression. I’ve used electrosurgery before with mixed results. I’ve never used a soft tissue laser and I know some clinicians swear by them. The thing that all of these things require is anesthesia on (at least) the palatal or lingual for comfort. If you don’t have some solid gingival anesthesia, you’re cannot use cord, electrosurgery or a laser comfortably. In some cases, this gingival anesthesia is only necessary for tissue retraction. Usually, you can prepare a tooth without it. So, I’ve routinely used my paroject for profound gingival anesthesia and placed cord. Which is the most tedious job in dentistry, I think.

I don’t like placing cord, but I’m O.K. at it. When done well, you get great retraction. Often, it doesn’t do a red hot job with hemostasis without adding some kind of astringent. I’m a fan of Astringident X from Ultradent. I can still hear Dr. Fischer of Ultradent explain, “I could stop bleeding from the aorta with this stuff.” Anyhow, I hate cord. I’ll use it, but I hate it.

So then I hear about this stuff from 3M. The “retraction capsule.” I saw ads for it on DentalTown and thought it looked interesting. But it looked a lot like Expasyl, which I had tried and didn’t think that much of. It needed a special gun and was really tough to rinse off. So I was skeptical. Then a couple friends of mine on Facebook started raving about it and even putting up some case studies. So I thought I’d try it.

The “retraction capsule” fits in any standard composite compule gun. When you dispense the stuff, it comes out quickly. You don’t need to use a lot of pressure like with Expasyl. It doesn’t have a ton of body, but it seems to expand slightly after you dispense it. I think this is where you get the retraction. The tip of the capsule is very thin. Slightly thicker than a periodontal probe, but it slips under the gingiva quite easily. The instructions suggest letting it sit for a couple of minutes. After that, you rinse vigorously (and I mean vigorously). I go into the sulcus with an Ultradent Dento-Infusor tip on a small syringe of isopropyl alcohol for a vigorous rinse and removal of any handpiece oil, etc. What you end up with is a very clean and dry preparation with nicely retracted sulcus.

The impressions are good. Really good. I’m getting marginal flash in places where I never got it before. And better than that…no cord! I’ll place it when I need to, but so far I haven’t had to use it for the better part of a month. Which makes working more fun. Which is pretty much my main concern around here. 

My main problem with this product is the name. “3M retraction capsule” is clearly not sexy enough. I started calling it “paste” at first. Now I just ask for “magic impression goo” and Shelly gets it for me.

I won’t even charge 3M for the name if they want to use it.

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  1. Dear Dr. Mead,
    We’re – a blog providing dental business advice to our 10,000+ dentist readers. We wanted to ask your permission to repost this article. Many thanks.