Zahn Dental Sales - January/February 2018 - 14

Efficiency and Accuracy in Denture Base Processing
Dennis Urban CDT

As we look at where the dental laboratory industry stands with acrylic denture base processing and as I travel around the country lecturing and training on removable
technology, I find that removable dental technicians still advocate the old reliable technique in which removable technology was built.
Press packing is still the most widely used method in acrylic processing followed by injection and then by pour acrylic techniques. The success and accuracy of these
techniques depends on the right materials and of course the expertise of the technician. I am a big fan of heat cured acrylic and have also been a longtime advocate
of microwave curing. There are many differences in quality on many of the heat cured acrylics out on the market. I judge an acrylic by natural shade, the strong bond
between denture base, flexural strength, impact resistance, bond to denture teeth and finishing and polishing qualities. I also look for a low shrinkage rate in an acrylic.
Diamond D® from Keystone Industries is the one acrylic that has been consistent in all of these qualities over the years. Those who know me in the industry know that
I do not compromise when it comes to quality. I am only interested in giving the patient the best possible case with the ultimate in aesthetics and function, so when
Keystone Industries introduced their new Tecnoflask for microwave denture curing, I was very excited to test out this flask with Diamond D® acrylic. The results were phenomenal. I got the same quality
results time after time. I can now cure a denture in 4 minutes in a 500w-700w microwave oven utilizing Diamond D® 20 minute monomer or cure for 9 minutes using regular heat cure monomer. Made
of the best thermoplastic material suitable for a conventional microwave oven, the thickness and overall shape of Tecnoflask makes it stand out from competition. Tecnoflask's toughness and resistance
makes it safe against continuous pressure and high temperatures with no damage done to the mufffle. I use these flasks every day at our lab with peace of mind that every case is going to be a quality
one. You can even cure metal partials, hybrid and bar cases with microwave technology. Another plus is that the acrylic is being cured from the inside out resulting in virtually no free monomer after
curing. This is very important for patients who have a sensitivity to monomer.
The following is the Tecnoflask Diamond D® microwave technique:
1

1) Wax up denture for finish in the
normal manner. (Figure 1)
6

5) Mix up type 3 gypsum and vibrate
into flask, filling entire flask. (Figure 6)

10) When material is ready to pack
(comes away from jar without
sticking but not at snap stage),
pack into flask and trial pack.
(Figure 11)
16

14) Take flask out of microwave and
bench cool for 20 minutes. Immerse
in cold water for 5 minutes and
deflask. (Figure 16).

2) Invest denture in bottom half of Tecnoflask in a half and half mixture
of plaster and stone. (Figure 2 and 3)
7

6) After gypsum is set, remove bolts
and insert flask in microwave and set
timer for 1 minute and 30 seconds.
(Figure 7)

11) Make sure metal protector is
placed on top of flask when packing.
This will ensure longevity and protection for the Tecnoflask. (Figure 12)

3) After gypsum has set up, Vaseline
all gypsum areas. (Figure 4)

7) Open flask, remove the bulk of the 8) Paint on Diamond D separator
wax and boil out the remaining wax. (2 coats works well). (Figure 9)
Clean all waxy residue off teeth and
prepare teeth by roughening ridge lap
of teeth or if desired make diatoric
holes for added retention. (Figure 8)
13

12) Open flask, remove excess and add more acrylic. After pressing,
remove excess again, paint model with Diamond D® separator, close flask
and tighten bolts. (Figure 13 and 14)

4) Attach top half of flask and tighten
all bolts. (Figure 5)
10

9) Mix Diamond D heat cure acrylic
and 20 minute monomer according to
manufacturer's guidelines. (Figure 10)

13) Place in Microwave and cure for
4 minutes. (Please note, if using heat
cure monomer, cure denture for 3
minutes at 40% power, 3 minutes
at 60% power and 3 minutes at
90% power. Microwave can easily
be programmed for all three power
levels). (Figure 15)

15) Check occlusion (Figure 17) and finish and polish denture (Figure 18 and 19).

Denture technology has been making some significant advances in materials and technique's including more natural looking and wear efficient denture teeth. With the recent introduction of digital
technology, we are likely to see even more changes in the way we approach removable technology. Keep in mind that even with digital technology, a denture base resin is still being utilized whatever
the method the digital denture is being made. All in all, utilize materials and methods which are consistent in producing quality. Show off your technical talents by bypassing methods which will sacrifice
doctor and patient expectations and keep patient satisfaction in mind.

Zahn: www.zahndental.com * CAP: www.cap-us.com * CMC: www.custom-milling.com

http://www.zahndental.com http://www.cap-us.com http://www.custom-milling.com

Table of Contents for the Digital Edition of Zahn Dental Sales - January/February 2018