No New Equipment, Special Training or Processing

By | Dr. Gettleman's Blog

b5658fb1-37d6-4f3a-8763-713178ffda28Dr. Lawrence Gettleman is a professor of prosthodontics and biomaterials at the University of Louisville School of Dentistry. He invented Novus and was on the team that obtained its final patent. > Click here for more about Dr. Gettleman


 

A big reason many dental labs prefer Novus liners is that they can use conventional hot water processing with equipment they already have and know how to use, which allows them to avoid the costs of buying new equipment and retraining staff.  Processing doesn’t take much more time than with other soft liners.  Some liner products process for many hours or require boiling.  There’s even one on the market now that takes fourteen hours!

Another Novus time-and-money saver is that it helps avoid waste.  Any excess that oozes out during packing can be recovered and put in areas where there isn’t any excess, or saved for the next denture. So there’s almost no waste if you’re careful, probably less than 5%.  Most labs want to minimize the amount they throw away, especially a specialty material like Novus.

PNF Rubber – A Space-Age Material

By | Dr. Gettleman's Blog

b5658fb1-37d6-4f3a-8763-713178ffda28Dr. Lawrence Gettleman is a professor of prosthodontics and biomaterials at the University of Louisville School of Dentistry. He invented Novus and was on the team that obtained its final patent. > Click here for more about Dr. Gettleman


 

PNF rubber (Polyphosphazene fluoroelastomer), the main component in Novus liners, was first developed at Penn State University.  I was part of the team that obtained the final patent for it in 1987.  Dentists and lab technicians can learn its basic chemistry from that patent.

Although it’s been FDA-approved for many years, PNF hasn’t always been readily available to industry, mainly because it’s a specialty polymer that is expensive to produce and the right company hasn’t stepped up to take full advantage of its many useful properties. It’s been used for a variety of applications in the defense and aerospace industries, although not as much as it could and should have been.

Radiopacity matters!

By | Dr. Gettleman's Blog

b5658fb1-37d6-4f3a-8763-713178ffda28Dr. Lawrence Gettleman is a professor of prosthodontics and biomaterials at the University of Louisville School of Dentistry. He invented Novus and was on the team that obtained its final patent. > Click here for more about Dr. Gettleman


 

Everything we use in bio-medicine should be X-ray opaque in one way or another so that it can be identified it if gets into the wrong place. Say a denture shatters in an auto accident and a piece of it gets up into the nose or throat, or even a lung. That doesn’t happen very often, but when it does, it can be life-threatening. Those pieces need to be found, removed, and then you need to go back and take more radiographs to make sure they have been removed.

So that’s another great thing about Novus.  Acrylic by itself is the same density as carbon-based soft tissues and is essentially invisible to X-rays, but Novus includes barium sulfate as a filler, which imparts X-ray opacity.  Also, if a denture breaks or shatters, Novus tends to hold the pieces of the acrylic denture base together, which means small pieces of material may not break off and cause trouble.

I Love Boney Undercuts

By | Dr. Gettleman's Blog

b5658fb1-37d6-4f3a-8763-713178ffda28Dr. Lawrence Gettleman is a professor of prosthodontics and biomaterials at the University of Louisville School of Dentistry. He invented Novus and was on the team that obtained its final patent. > Click here for more about Dr. Gettleman


 

When I teach, I often take my students to observe surgeons extracting teeth for denture preparation. I try to stop the surgeons from removing excess bone unless it is really extreme.  With Novus in particular, the denture can engage over a bony exostosis, torus, retained tooth, implant head or some other protrusion and it locks into the undercut. The liner has to be carefully adjusted because it engages very tender tissue. That’s another advantage of Novus — almost any rotary instrument can be used to make adjustments. With silicone liners, unless you use special adjusting wheels and devices, instruments either bounce off and do nothing, or they gouge in and create feathers and other defects in liners.