Which milling machine is the best for custom abutments ?

[cadfan]

If you want to mill abutments from pure ti around 200-250 K

http://www.gfms.com/country_CH/en/P...high-speed-machining-centers/hsm-200u-lp.html

For bars, preforms and with a bit knowlege some geometries from pure titan iron cast frame and high power servos for longrun 75 K plus cam fly to Frankfurt and take a look for a few days payed in a year .

https://www.mbmaschinen.de/index.php/cobra-mill-5a1-334.html

 

[Beatrice]

I find this post amusing!

The best machine does not exist, they all break and are all no reliable, they all cost a big amount of money in maintenance, training and installation.
Plus at the end they are useless if you don't know what to do.

Not because you know how to drive a car you know how to drive a F1.
Same with this kind of machine, if you are a dental technician stop trying to open freaking milling center that will run bankrupt anyway within 2 years.
Go back to school bench, learn CNC machinery and then, think about it.

A real milling machine will cost you 250K plus installation, plus special electricity output, your building will need to be in a light industrial zoning place with probably higher taxes, you will need some installation for liquid and also specific high-end air pressure system. On top of that, you will need some other machine shop equipment to load or unload your blanks, you will even have to design your own blank holder to optimized everything. After you will need some very powerful computer with very high cost software that nothing is explain how they work, you need 3-4 years of school to learn how to use this kind of software to program milling path.
You will need 1 employee to run the software, 1 to run the machine 1 to repair the machine etc etc etc.

Before you reach the volume to be break even you will probably be bankrupt except if you do have millions of $ to spend over 3 to 5 years. You will have also to develop all geometry for every damn 400 implant brand, just that will take you over 5 years to get all of them with 1 to 2 engineers doing only that. To be able to develop them, you will need to buy original part from all implant company that cost a LOTS of money.

Not enough to convince you to avoid this?
Well let's get to scanner, you will probably buy a 3shape or Medit or an Imetric but you will use scanbody, right there your are outdated. These work, but are limited and lower the end precision of your product. If you want to be a real milling center like few out there (not sure we reach 10 in the whole world seriously) you will need to be able to scan the analog itself on the model.
As soon as you wont be able to do an implant platform your customer will go elsewhere and you might lose him.

I mean, seriously, there couple of industrial milling center out there and a big bunch of lab that think they are milling center, why 1 more? Your only argument over all of them will be pricing. NO!, good service is not an argument we are many offering excellent customer service for real, some small and even some big ones are doing amazing feats to give a unique customer service trust me and ask around many names will come out.
So at the end you will need to do the price battle, trying to sell an implant bar at 399 or 499 USD $ to compete with the other milling centers, you will not make your number and you will find it hard.

It a known fact that my bars and abutment are in the high price range and funny it is, i almost double my volume year after year even with milling center offering 50% lower prices then mines, why? Because we are doing that for over 15 years and we have invest in this kind of machine to offer (in my opinion) the best quality in the market and dental technician are all about quality as far as i learned working with you guys!

Never seen any painter in my life that loved working on a cheap canvas. And yes Canvas can cost a lots of money for quality, but will make the art unique.

So, what is the best machine? Define your needs. Axxys seem to sell very good machine for a low volume for your own use. Willemin-macodel are probably among the best for custom abutments but definetly very expensive and very hard to use. Mikron, DMG, etc are probably best for bridges and bars.


Ohh did I miss to tell you, the best abutment machine is the worst for bar and the best for bridges and bars is bad for abutment?
yeah, that true.

Another point, milling from pre-milled blank is bad. Yes people do it, the problem is the way you hold the blank you put pressure on the actual hex of the future abutment and you "twist" it in matter of microns and at the end if you compare with an original "off the shelf" yours will be very bad. That why swiss turn kind of machine are the best since they mill the hex every time.

ohh boy, i forgot to talk about CE mark and FDA, and etc.

And not least, do you know how much is a "micron"?
I am asking cause giving lecture for 10 years now, i ask this question at every lecture I give, around 2% of dental technicians in all the lectures I gave knew the answer. And no, they are not stupid, it just not something you learn and need to know when you do dental technique!
But it is something you have to know on your first day when you are doing machinery.

Hope this help. seriously, i am not here to say I'm better, neither to stop your dream. You want to open a milling center i will be behind you for real. I don't mean new competitors, that free market. Just think twice either you or everyone reading this post.

One of your colleagues said it, outsource! Keep the focus on your ART, your training, your certificate on the wall of you lab. Learning a new job it hard. doing 2 job in same time is so complicated! Few have achieved it and succeed, not saying you cannot be one, I am saying that some of the best and biggest lab in the world don't even own a single machine!

Best

 

[cadfan]

@ Beatrice Robichaud just for my understanding how comes pessure or more pressure on a interface of a preform thats fixed on the opposite side and why is this more than done with the right mill ???

you know the studys about implant impression accuracy either splinted or not 100 micron and more ?? or around one and a half hairs


Bars are most times done with stupid multi vs non engaging interfaces not to much intellektuell if placed well adding attachments or using the right scanmarker is maybe more a challenge the biggest challenge is minimize human error in the practice i think you jump a bit to short but i like what your doing.

mill your bars at 37 degrees temperature .

 

[CoolHandLuke]

just to add to it, Beatrice, you can spend 250k on a machine and if you are the kind of person that reads the literature and believes every word to be true, you can buy a bad machine.

with proper cnc knowledge and expertise you avoid the players in the "dental" market that try to trick you. there are bad machines out there, making victims of people with more money than intelligence.

for example, "high end" zirkonzahn, imes, or cerec and planmill. genuinely overpriced and underperforming.

then you need to be able to know the difference between mathematical modeling simulation, and toolpath simulation, not all CAM is created with equal ability. we can prove for example that the simulation power of software like sum3d is better than the simulation power of most other CAM on the market, even though their power to acheive perfect milling is less. software like sprutcam will be more flexible to postprocess for a huge amount of machines, where many other softwares take ages to get new postprocessors installed.

you cannot simply press a button and become a machine center; there is no magic number of money that makes it happen. it is a team of professionals led by a team of technically adept individuals, not accountants, that ensures quality output.

too many labs are run by accountants, dollars are the only thing that make cents to them. haha. don't know or care how good or bad output is as long as their clients keep coming back.

 

[Beatrice]

@cadfan
There is multiple way to mill custom abutment :
1- https://www.youtube.com/watch?v=ApEk-K2QDrQ
In this exemple, the problem is productivity, you get a very good abutment, like for real! One of the best, problem is on the milling center, this kind of machine is good for doing the same parts multiple times, not a unique piece each time, it mean it required a huge human effort to develop a good milling tool path very quick to have quick turn around time. Few company have specialized in them (like the one in the video) and succeed with this solution. It a very high cost solution but a good one

2- https://www.youtube.com/watch?v=XUawVvubj80
This is one of the most common way to do, the problem is the whole blank is hold by the hex then you get a 70000rpm milling machine that hit the top part, it put high pressure on the hex, this is probably the worst way to work but the lower cost possible to manufacture an abutment.
Huge benefit, you don't need to be FDA approved for that, the blank need to be, not the milling company.

3- http://www.protecdental.com/sites/default/files/Custom%20Abutment%20FPA2%20milling.png
This way to mill is probably the second most use technique, the hex is protected but the problem is the final product is not accurate, since you have to hold around the screw hole, more human work will be needed to removed it and you will be different then the original cad file in the surrounding. For an abutment it might be okay but for a full crown it can be problematic, when you think cad-cam should increase precision, not the other way around.

4- http://www.workncdental.com/UserFiles/377/Image/Dental-slider-1.jpg
Milling from a blank will give you amazing result, problem is some implant connection "ie: camlog" will be impossible to replicate even with a real time 5 axis machine.
Thing said, the quality will be outstanding on the top end of the abutment, probably among the best.
Depending of your machine and your disc holder you might be limited in some shape

5- The last technique is used by Willeman Macodel machines, it a mix between swiss turn and a real 5 axis machine.
They use the strategy of number 1 and 4 giving all hex possible and the best surface finish.
Yet, this required a lots of work to develop software and programs all implant platform but the result is amazing

Technique 1, 4 and 5 in USA will required to be FDA approved since the hex is mill by the milling center.


As for precision, the study show that a passive fit should be under 10 micron, Brannemark made one of the first study on this topic and many other was publish after.
If you use scanbody right there you are technically off according to science.
I give an hour lecture about why and how scanbodies create this problem. (could make a topic on that later one.) Thing said, at the end whatever the precision is done with the product it still related by the dentist need and patient tolerance.

So a very bad product according to science might be good enough for this patient if he don't complain...