Monolithic E.max vs Zirconia - pros and cons?

[Contraluz]

Good day, community

I would like to see what in your experience and opinion the pros and cons are from one material over the other. I then would like to use the findings in a ppt presentation over said materials. A few of the answers may seem to be obvious. Nonetheless I would like to see what you guys think.

Thank you very much in advance!

Michael

 

[rkm rdt]

Anterior or posterior?

 

[Ken Knapp]

Good day, community

I would like to see what in your experience and opinion the pros and cons are from one material over the other. I then would like to use the findings in a ppt presentation over said materials. A few of the answers may seem to be obvious. Nonetheless I would like to see what you guys think.

Thank you very much in advance!

Michael

I think for the most part the New esthetic Zirconia are equal to or better than e-max esthetcially in the anterior/posterior. The New zirconia are stronger ~700Mpa vs 375Mpa, require less tooth prep and are not fussy about margin prep. Emax tends to chip around the margin during finishing. The only negative is that zirconia cannot be bonded and some dentists want to bond their inlay/onlays and prefer emax for that. I discontinued emax and have several dentists that use zirconia for inlays/onlays/veneers without any problems. My lab is an All-Ceramic Zirconia only Lab.

 

[2thm8kr]

3 different translucency levels for emax CAD, 4 if you count pressable multi ingots. Zirconia manufacturers starting to bring different translucency options to market.

Molecular structure of emax more closely resembles natural teeth. Light reflects and refracts similar to natural teeth. Easier to match value with emax, matching value sells anterior crowns.

Limited spans with emax for bridges. Limited to anterior region and enough vertical dimension for proper connectors, 16sqmm is a lot. Would never use emax bridge on anyone with flaaaaat occlusion.

 

[Contraluz]

My lab is an All-Ceramic Zirconia only Lab.

Thank you very much, Ken

Interesting your comment on inlays/onlays and veneers...

Since you are all Zr, what is the feedback in respect to the removal of a restoration? In my experience, this is one of the big cons.

 

[Contraluz]

Anterior or posterior?

Both. But only monolithic...

 

[Contraluz]

Would never use emax bridge on anyone with flaaaaat occlusion.

Thank you, 2thm8kr! You certainly have a point there...

 

[CoolHandLuke]

this is one of the big cons.

why?



quick demo of how easy it is.

 

[2thm8kr]

why?



quick demo of how easy it is.

I've seen some techniques using fine diamonds and a tapping motion on the crown/bridge. Tapping helps prevent heat build up in the binders on the diamond and the bearings of a handpiece.

 

[Contraluz]

why?

Well, that is the feedback, I get, when talking to my clients in respect to zirconia. Just recently, a client of mine had to cut off full zirconia veneers on the canines (not my case...),where she spent several burs and quite a bit of time.

Although, the more translucent zirconia should be rather easy to cut off.

quick demo of how easy it is.

I will refer to this video, from now on, when the question comes up...

Michael

 

[Ken Knapp]

Thank you very much, Ken

Interesting your comment on inlays/onlays and veneers...

Since you are all Zr, what is the feedback in respect to the removal of a restoration? In my experience, this is one of the big cons.

Removing Zirc crowns only a problem for the untrained. The video noted on this thread notes the correct burs to use that makes removal easy. I have several dentists that were amazed how easy it can be with the proper burs and technique.

 

[biodentg]

Pressing emax takes more time and labor than zr. Many things can go wrong during this process and an emax remake is a pitå.

 

[DentalTechTips]

Pressing emax takes more time and labor than zr. Many things can go wrong during this process and an emax remake is a pitå.

Conversely... Milling e.max takes MUCH less time and labour than Zr...

A traditional Full Zirconia crown will take 15 minutes to scan and design, 15 minutes to mill, any green state contouring/colouring could take another 30 minutes and an 8-12 hour sintering cycle. Final polishing/fitting: 5 minutes, staining and glazing 15 minutes.

So Zr is anywhere between 9.5-13.5 hours to finish... (keep in mind that this figure compounds based on the amount of units going into the sintering furnace)

Milled e.max takes 15 minutes to scan and design, 15 minutes to mill, 15 minutes blue stage contouring/fitting, 30 minutes crystallization, and I prefer to do an extra characterization bake with some cut back which adds another 30 minutes.

So e.max is 1.25 to 1.75 hours to finish. (crystallization also compounds this figure downwards with more units per cycle)

 

[Contraluz]

Pressing emax takes more time and labor than zr. Many things can go wrong during this process and an emax remake is a pitå.

Any remake is a pita...

And yes, e.max is rather technic sensitive, going the traditional wax/invest/press route.

 

[Contraluz]

Conversely... Milling e.max takes MUCH less time and labour than Zr...

A traditional Full Zirconia crown will take 15 minutes to scan and design, 15 minutes to mill, any green state contouring/colouring could take another 30 minutes and an 8-12 hour sintering cycle. Final polishing/fitting: 5 minutes, staining and glazing 15 minutes.

So Zr is anywhere between 9.5-13.5 hours to finish... (keep in mind that this figure compounds based on the amount of units going into the sintering furnace)

Milled e.max takes 15 minutes to scan and design, 15 minutes to mill, 15 minutes blue stage contouring/fitting, 30 minutes crystallization, and I prefer to do an extra characterization bake with some cut back which adds another 30 minutes.

So e.max is 1.25 to 1.75 hours to finish. (crystallization also compounds this figure downwards with more units per cycle)

Thank you! Good points!

 

[biodentg]

Conversely... Milling e.max takes MUCH less time and labour than Zr...

A traditional Full Zirconia crown will take 15 minutes to scan and design, 15 minutes to mill, any green state contouring/colouring could take another 30 minutes and an 8-12 hour sintering cycle. Final polishing/fitting: 5 minutes, staining and glazing 15 minutes.

So Zr is anywhere between 9.5-13.5 hours to finish... (keep in mind that this figure compounds based on the amount of units going into the sintering furnace)

Milled e.max takes 15 minutes to scan and design, 15 minutes to mill, 15 minutes blue stage contouring/fitting, 30 minutes crystallization, and I prefer to do an extra characterization bake with some cut back which adds another 30 minutes.

So e.max is 1.25 to 1.75 hours to finish. (crystallization also compounds this figure downwards with more units per cycle)

I was talking about pressing, yes milling emax is a a different story
BUT, it is more expensive.
If you are willing to accept the extra cost involved then it is the way to go.

 

[CoolHandLuke]

Conversely... Milling e.max takes MUCH less time and labour than Zr...

A traditional Full Zirconia crown will take 15 minutes to scan and design, 15 minutes to mill, any green state contouring/colouring could take another 30 minutes and an 8-12 hour sintering cycle. Final polishing/fitting: 5 minutes, staining and glazing 15 minutes.

So Zr is anywhere between 9.5-13.5 hours to finish... (keep in mind that this figure compounds based on the amount of units going into the sintering furnace)

Milled e.max takes 15 minutes to scan and design, 15 minutes to mill, 15 minutes blue stage contouring/fitting, 30 minutes crystallization, and I prefer to do an extra characterization bake with some cut back which adds another 30 minutes.

So e.max is 1.25 to 1.75 hours to finish. (crystallization also compounds this figure downwards with more units per cycle)

and then 15 more minutes to rescan, redesign, remill because once crystallized it broke on first contact with the die.

or you suddnely saw the mill mess up your margin

or it pushed your unit out of the blank before properly calculating (https://drive.google.com/file/d/0B541pLNQsJ89MzhVVzZVb3pUOHM/view?usp=sharing)

milled emax is a huge headache and highly inconsistent system-to-system. what may work for milled emax in planmill might not work for milled emax on a versamill. its two different approaches to the calculation, and two very different outcomes (and block pricing)