Effect of die spacer on the seating of cast restorations on composite core preparations

Effect of evaporation and mixing technique on die spacer thickness: A preliminary study

“…The presence of the spacer provides space for the luting agent. The use of die spacer reduces elevation of the casting restorations, 5,7,12,13,15,18,19,[21][22][23] decreases seating time, 7 improves outflow of excess cement, 20 and lowers seating forces. 7 Conflicting evidence exists on the effect of die spacer presence on clinical crown retention.…”

“…[3][4][5][6][8][9][10][11] Internal relief, or venting of the casting, can overcome the effects of luting agent hydraulic pressure. [2][3][4][5][6][7][8][9][12][13][14][15][16][17][18][19] The use of venting requires drilling holes in the casting. The casting is cemented in place and the vent holes filled.…”

The effects of die‐Spacidng on post‐cementation crown elevation and retention

“…They noted a decrease in crown elevation from 649 m for crowns without spacer to 29 m for crowns with four layers of new (i.e., unopened) spacer and a decrease in crown elevation 16 used two 20-25 m layers of Tru-fit die-spacer to provide die relief. Oliva and Lowe 17 applied four layers of Tru-fit die-spacer to dies using a carefully controlled technique designed to produce an even thickness. They measured the thickness of four layers of die-spacer at five points on sectioned dies and noted a wide range of film thickness with a mean of 79.24 7.20 m, averaging 19.81 m per application.…”

Post and core systems, refinements to tooth preparation and cementation

“…61 Clinically this is not a problem as the technician places die relief on the master die in the laboratory and this allows for any microscopic exapansion. 62 More recent dual-cured, fibre-reinforced core materials have been introduced such as ParaCore (Coltène/Whaledent, Altstätten, Switzerland) and Build-It (Pentron Corp. Wallingford, CT USA) (Fig. 12).…”