Materials and Methods: The following mechanical properties were investigated, whereas EliparTM FreeLightTM 2 (3M ESPE) was used for light curing. For FS, CS and VH samples were stored for 24hr in tab water at 36 °C. In addition FS and CS were also measured after a 10h boiling stress test (BST).
Flexural strength(FS): Test specimens: 2x2x25mm (n=5); light curing: both sides 3x20s; measurement: universal testing machine, crosshead speed of 1mm/min.
Compressive strength(CS): Test specimens: 3x3x5mm (n=5); light curing: both sides 20s; measurement: universal testing machine, crosshead speed of 4mm/min.
Vickers hardness(VH): Test specimen: Disc d=15mm, h=1,5mm; light curing: both sides 5x20s; measurement: n=6, LECO micro hardness tester (15s, 200g).
Water uptake(WU): Determination of the water uptake was done according to ISO 4049:2000.
Linear swelling(LS): FS test specimens (n=3); measurement: length, initial and during storage in tab water at 36 °C.
Results: The following table shows the testing results. Standard deviations are given in parentheses. All data per method were analyzed by ANOVA (p<0.05). Means with the same letters are statistically the same.
Test methods: FS[MPa]: Vts 111(6)a, Exp-SA 100(7)b; FS[MPa],BST: Vts 67(4)A, Exp-SA 80(9)B; CS[MPa]: Vts 328(10)I, Exp-SA 319(10)I; CS[MPa],BST: Vts 318(5)u, Exp-SA 342(18)v; VH0,2: Vts 29,0(0,2)i, Exp-SA 50,0(1,7)ii; WU[µg/mm3]: Vts 64(1)aa, Exp-SA 28(1)bb; LS[%],60d: Vts 1,15(0,04)xx, Exp-SA 0,83(0,06)yy.
Conclusions: Within the test plan Exp-SA was found to have statistical significant better results in VH, WU and LS than Vts. Exp-SA showed lower initial FS than Vts, but after BST the FS were statistical significant higher. Equal properties were found for initial CS, while after BST the CS decreased for Vts and increased for Exp-SA.