Hi All,
Sorry for the absence lately, been tied up a lot lately (and not in a good way
).
The PM7/5/3 are not limited to IV materials. They can use any 98.5mm disk out there. Blocks do require the PM mandrel, so only our materials right now (although there was an adapter for Sirona mandrels that fit the Wieland mills that should work in the PM 7 as well, if it's still available, but I can't guarantee it will work perfectly).
Milled lithium disilicate takes between 35 and 50 minutes depending on the size of the restoration.
The mill is made to switch automatically from dry to wet to dry. It still needs cleaning daily, but overnight it is able to move from dry milling to wet grinding with no problems, this is the order I recommend because of the "concrete" issues mentioned above. Then give it a quick wipe out with windex and damp rag and allow it to dry briefly before going back to dry milling. This will remove the stickiness of the lubricant from the surfaces so the zirconia dust does not stick to everything. Having said that, I have gone back and forth from wet to dry to wet with no issues, and due to the construction and shape of the milling chamber have had no issues.
lithium disilicate margins on the PM7 are very good, but of course this also is determined by the prep design as well. I don't know of a mill that will do really thin feathered or beveled margins with glass.