Nested a full‑arch cutback in multilayer HT zirconia, simulated shrinkage, did a PMMA try‑in with a 30 µm cement gap, and everything was perfect — until 4:26 pm, when the silicone matrix turned it into a propeller on the articulator. Do your restorations also wait for the most innovative material combo to debut their slapstick routine, or is my 0.6 mm finishing bur the secret heckler?
@OP After my own 4:26 p.m. helicopter, I started punching two 1 mm vent holes in the silicone matrix at the canine embrasures and dusting it with a light separator, so it seats without vacuum and the arch stops spinning. If the multilayer HT still wants drama, I nudge the PMMA try-in gap from 30 µm to about 40 µm around the abutments, but the vents usually do the trick.
Been there, @OP — two tiny cured block-out resin stops inside the silicone at the first molar fossae killed my helicopter by breaking the vacuum. > from 30 µm to about 40 µm around the abutments, but the vents usually do the trick. (I stay at 30 and skip vents; the micro-stops make seating boring in the best way — worth a try?).