A study was conducted on the hardening time of three Grossman's cements with different powder particle sizes (60, 100 and 150 mesh) using Specification n. 57 of the AMERICAN DENTAL ASSOCIATION1 (1983). The cement obtained from mesh 150 particles showed the longest hardening time (22 minutes), which was different when compared to mesh 60 (17 minutes) and 100 (17 minutes) particles.
Dental cements; Particle size; Setting time
| Cements | 60 mesh | 100 mesh | 150 mesh |
| Powder/fluid ratios | 5.55 g/1 ml | 5.45 g/ 1 ml | 5.60 g/ 1 ml |
| Spatulation times | 82 s | 81 s | 104 s |
|
Cements tested Replications |
60 mesh | 100 mesh | 150 mesh |
| 1 |
16 |
16 |
20 |
| 2 |
18 |
16 |
22 |
| 3 |
17 |
19 |
24 |
| Mean |
17 |
17 |
22 |
| Pairwise sample comparison | Differences between mediun ranks |
Citical values (a) 0.05 |
Significance |
| 60 mesh versus 100 mesh |
0.3333 |
5.24 |
ns |
| 60 mesh versus 150 mesh |
4.3333 |
ns |
|
| 100 mesh versus 150 mesh |
4.6667 |
ns |
