Have you ever used Fermit? It’s one of my favorite materials.
Every now and then you find a material that makes life so much easier. It never fails you and you just want to rant and rave about it. For me, Fermit is one of those beauties.
Manufactured by Ivoclar, Fermit is a paste of a bunch of polymers that light cures to a highly elastic state. That means it’s easy to smush into a space, quickly cure, then easily remove when you need to.
I use it exclusively for two things and two things only. But it does those two things so darn well.
(1) Inlay/Onlay Temporization
I used to use IRM and that was silly of me. There are three problems with using IRM as a temporary material for inlays and onlays. First, you’ll have drill it out which can alter the preparation if you’re not careful. Second, you have to get the patient anesthetized for the insertion visit because you have to drill it out. Third, there have been concerns in the literature that IRM will interfere with the bonding of your inlay/onlay, especially if you are using a resin cement.
Fermit can quickly be pressed into the preparation and cured. I have never seen any concerns about it interfering with bonding in the literature. And it quickly pops out when you are ready to insert the inlay/onlay, no need for drilling or anesthesia.
Inlay Preparation Filled with Fermit
(2) Implant Access Hole Obturation
I’m a big fan of doing things screw-retained as opposed to cement-retained. I’ll explain that in another post. Anyway, when I insert a screw-retained case, whether it’s a single unit or a full arch, I always place Fermit and a cotton pellet in the access holes for a two week trial period. In my experience, if an screw is going to loosen or the patient is going to have an esthetic or functional problem, it will usually happen within the first couple of weeks after insertion. So retrievability is especially important in those first two weeks. I need to be able to gain access to the abutment screw or prosthetic screw without breaking a sweat. Fermit gets the job done. After the two week test drive, I’ll bring the patient in to place the final composite resin seals. This also give me an opportunity to review the patient’s hygiene practices with their new prosthesis.
Full Arch, "Hybrid" Prosthesis with Access Holes Obturated with Fermit
PROTIP: Pack a healthy sized piece of cotton into the access hole up to the brim, then push it down with the Fermit. You want the cotton to come out with the Fermit when you remove it. Removing cotton that was packed way too far down and not in contact with the Fermit can be a real pain.
A Fermit and Cotton Plug