Implantation, Vascularization & Maturation Timeline
Day 0–28 integration: implant → capillary sprouting (D3–7) → anastomosis (D10–14) → perfusion (D14–21) → follicular maturation and shaft eruption (D28+).
Implantation proceeds with the robot positioning the cartridge needle along the AI-generated 3D matrix and the voice-coil actuator driving needle penetration to a depth controlled by the surface depth-map plus a fixed 1.4 mm offset into the reticular dermis. The follicle–scaffold construct is then ejected by the plunger and released as the needle retracts.
Days 0–2 are dominated by hemostasis and platelet release of PDGF. From day 3 through day 7, endothelial sprouts driven by the VEGF gradient migrate from peri-implant capillary plexus into the basal microsphere zone of the scaffold. Anastomosis with host vasculature is observed by day 10–14 (perfusion confirmed by laser-Doppler).
By day 21 the engineered follicle is fully perfused and the LEF1⁺ hair germ progresses through the elongation phase. First pigmented hair shaft emergence is observed on day 24–28 in pre-clinical large-animal studies (n = 12, mean = 26.4 d, σ = 1.8 d).
Local perfusion fraction measured by laser-Doppler imaging at each integration stage.
| Parameter | Value | Unit | Tolerance / Note |
|---|---|---|---|
| Implant depth | 1.4 | mm | Below surface, reticular dermis |
| Capillary sprouting | D3–7 | ||
| Anastomosis | D10–14 | ||
| Full perfusion | D14–21 | ||
| First shaft emergence | 26.4 ± 1.8 | d | n = 12 large-animal |
| Engraftment rate | ≥ 92 | % | Day 28 |