| Score |
| Wrinkle Depth |
Class | 0 F | No wrinkle. | - |
0.5 F | Very shallow yet visible wrinkle | - | |
I F | Fine wrinkle | Visible wrinkle and slight indentation | |
1.5 F | Visible wrinkle and clear indentation. | 1-mm wrinkle depth | |
2 F | Moderate wrinkle Clearly visible wrinkle | 1- to 2-mm wrinkle depth | |
2.5 F | Prominent and visible wrinkle | More than 2 mm wrinkle depth |