Table 2.
Group distribution, reaction force and maximum principal stress peaks and failure risk for the clasp and the enamel according to the clasp material (elastic modulus - E) and undercut. (Reproduced from [109]. with permission from © 2020 Elsevier).
| Clasp Material | Retention (mm) | Reaction Force (N) | Stress Peak (MPa) | Failure Risk | ||
|---|---|---|---|---|---|---|
| Clasp | Enamel | Clasp | Enamel | |||
| Polyamide (E = 1.44 GPa) |
0.25 | 3.13 | 17.1 | 1.4 | 0.22 | 0.03 |
| 0.5 | 6.31 | 34.2 | 3.0 | 0.45 | 0.07 | |
| 0.75 | 9.47 | 51.1 | 4.5 | 0.68 | 0.11 | |
| Polyoxymethylene (E = 3.15 GPa) |
0.25 | 4.53 | 45.7 | 17.2 | 0.26 | 0.41 |
| 0.5 | 8.65 | 67.8 | 21.5 | 0.32 | 0.51 | |
| 0.75 | 12.31 | 96.6 | 35.8 | 0.54 | 0.85 | |
| Polyetheretherketone-PEEK (E = 3.74 GPa) |
0.25 | 6.45 | 108.2 | 26.0 | 0.33 | 0.62 |
| 0.5 | 12.95 | 134.6 | 31.1 | 0.39 | 0.74 | |
| 0.75 | 18.36 | 189.9 | 38.2 | 0.48 | 0.91 | |
| Gold (E = 91 GPa) |
0.25 | 14.50 | 160.5 | 30.2 | 0.07 | 0.72 |
| 0.5 | 28.98 | 198.2 | 38.1 | 0.08 | 0.90 | |
| 0.75 | 43.41 | 202.1 | 44.1 | 0.10 | 1.05 | |
| Titanium (E = 110 GPa) |
0.25 | 17.81 | 230.9 | 32.2 | 0.07 | 0.76 |
| 0.5 | 35.63 | 241.1 | 39.8 | 0.08 | 0.95 | |
| 0.75 | 53.44 | 252.2 | 45.2 | 0.09 | 1.07 | |
| CoCr (E = 220 GPa) |
0.25 | 21.78 | 255.8 | 34.7 | 0.05 | 0.82 |
| 0.5 | 43.57 | 267.0 | 41.1 | 0.06 | 0.98 | |
| 0.75 | 65.37 | 297.9 | 46.4 | 0.07 | 1.10 | |