| S T A G E 4
L E E W A Y S P A C E |
| Birth to the complete primary dentition |
| 0.9 mm |
| First intertransitional period |
| First transitional period |
| Second
intertransitional period |
| Second transitional period |
| Adult dentition |
| 1.7 mm |
| R I C H A R D Y O O N |
| 32 |