The effect of cement thickness on the fracture strength of all-ceramic crowns.

The effect of cement thickness on the fracture strength of all-ceramic crowns.

Australian dental journal (1995-02-01)

M Tuntiprawon, P R Wilson

ABSTRACT

The effect of increasing cement thickness on the fracture strength of aluminous porcelain jacket crowns was investigated in this study. Thirty-three aluminous porcelain jacket crowns were divided into three groups. In Group 1, only platinum foil was used to provide cement space. In Group 2 two layers and Group 3 four layers of die spacer were painted onto the metal die before impression taking. Each crown was cemented onto a metal die with zinc phosphate cement and loaded until fracture. The maximum force to break each crown was recorded. The average fracture load was 408 N for Group 1,365 N for Group 2 and 324 N for Group 3. ANOVA (SPSS) found a significant difference (p < 0.05) between groups. A Scheffe Test revealed a significant difference between Groups 1 and 3. It was concluded that increasing the cement thickness above 70 microns reduced the fracture strength of porcelain jacket crowns.

MATERIALS

Product Number

Brand

Product Description

GF72819715

Platinum, foil, 25x25mm, thickness 0.25mm, as rolled, 99.99+%

GF05432936

Platinum, foil, 0.05m coil, thickness 0.030mm, coil width .7mm, as rolled, 99.95%

GF72566657

Platinum, foil, 0.1m coil, thickness 0.029mm, coil width .34mm, annealed, 99.99%

GF03272868

Platinum, foil, 4mm disks, thickness 0.125mm, as rolled, 99.95%

GF04529538

Platinum, foil, 50x50mm, thickness 0.125mm, as rolled, 99.99+%

GF48496977

Platinum, foil, 4mm disks, thickness 0.125mm, as rolled, 99.99+%

GF59323619

Platinum, foil, 15mm disks, thickness 0.01mm, as rolled, 99.95%

GF05324183

Platinum, foil, 8mm disks, thickness 0.1mm, as rolled, 99.99+%

GF00187163

Platinum, foil, 0.1m coil, thickness 0.15mm, coil width .9mm, as rolled, 99.99%

GF55534046

Platinum, foil, 0.05m coil, thickness 0.029mm, coil width .34mm, annealed, 99.99%

GF68611237

Platinum, foil, 0.2m coil, thickness 0.029mm, coil width .34mm, annealed, 99.99%

GF15087203

Platinum, foil, 0.1m coil, thickness 0.025mm, coil width 1.6mm, as rolled, 99.95%

GF96551354

Platinum, foil, 10mm disks, thickness 0.0075mm, as rolled, 99.95%

GF72782231

Platinum, foil, 50x50mm, thickness 0.1mm, as rolled, 99.99+%

GF43907799

Platinum, foil, 15mm disks, thickness 0.005mm, as rolled, 99.95%

GF13420257

Platinum, foil, 0.5m coil, thickness 0.025mm, coil width 5mm, as rolled, 99.95%

GF30259357

Platinum, foil, 25x25mm, thickness 0.125mm, as rolled, 99.95%

GF87686173

Platinum, foil, 30x30mm, thickness 0.2mm, as rolled, 99.95%

GF83172269

Platinum, foil, 0.05m coil, thickness 0.025mm, coil width .4mm, as rolled, 99.95%

GF58265488

Platinum, foil, not light tested, 50x50mm, thickness 0.004mm, as rolled, 99.95%

GF57762399

Platinum, foil, not light tested, 50x50mm, thickness 0.005mm, as rolled, 99.95%

GF99566410

Platinum, foil, 15mm disks, thickness 0.025mm, as rolled, 99.99+%

GF02102948

Platinum, foil, light tested, 25x25mm, thickness 0.025mm, as rolled, 99.99+%

GF73706058

Platinum, foil, 10mm disks, thickness 0.0125mm, as rolled, 99.95%

GF02450180

Platinum, foil, not light tested, 50x50mm, thickness 0.00075mm, permanent polyester support, 99.85%

GF52591462

Platinum, foil, 4mm disks, thickness 0.0075mm, as rolled, 99.95%

GF17993368

Platinum, foil, 10mm disks, thickness 0.125mm, as rolled, 99.95%

GF07973961

Platinum, foil, 0.5m coil, thickness 0.025mm, coil width .85mm, as rolled, 99.95%

GF06440048

Platinum, foil, 4mm disks, thickness 0.05mm, as rolled, 99.95%

GF60594442

Platinum, foil, 0.5m coil, thickness 0.025mm, coil width 8mm, as rolled, 99.95%