Method: Materials used was RelyX Luting Plus (3M ESPE). Cement was extruded into 2mmx2mm square glass tubes with 25mm length, then cured under different conditions and/or stored in 37oC DI water for several time periods before testing on Instron tester.
Result:
The mean values of flexural strength, including the standard deviations, are summarized in the following:
Flexural strength (MPa) build up under different conditions
Curing condition |
40s |
2min |
5min |
30 min |
24hr |
1w |
2w |
1mon |
6mon |
DC |
NA |
NA |
7.34+0.8 |
17.0+0.9 |
30.7+2.6 |
34.8+2.8 |
32.7+2.9 |
41.7+3.8 |
39.4+3.2 |
LC |
5.1+1.4 |
7.3+0.7 |
12.8+1.8 |
16.9+2.4 |
30.6+2.7 |
35.0+3.0 |
33.2+3.2 |
38.1+2.1 |
36.4+3.9 |
Conclusion: Light cure and dark cure samples continue to build up their flexural strength during 37C storage in DI water. ANOVA analysis was performed at p <0.05, there was no significant different for dark cure and light cure after 37C storage in water for specific time. A brief light exposure transforms the mixed paste cement into soft rubbery solid that provides easier excess cement clean up.