Background: Preservation of hair follicle units for the purpose of delayed transplant will help us graft thousands of hair grafts at one session, even in a clinic with fewer assistants and less equipment.
Objective: This study was undertaken to evaluate and compare the viability of hair follicle units preserved at 0 and 4 degrees C for various periods.
Materials and methods: Cell cultures and transplant of hair follicle units into athymic mice were performed.
Results: Outer root sheath cells could be cultivated in 96% (0 degrees C group) and 92% (4 degrees C group) of the hair follicles after 24 hours of preservation, whereas 85% (0 degrees C group) and 79% (4 degrees C group) of the follicles implanted into the mice regrew well after the same period of preservation. Then, in both the 0 degrees C and the 4 degrees C group, these rates decreased significantly with length of preservation in cell cultures and mice transplant; however, 0 degrees C seems better than 4 degrees C for preservation of grafts (p<.05).
Conclusion: Grafts are better preserved at 0 degrees C instead of 4 degrees C. When delayed transplant is an option, it should be completed within 24 hours and no later than 48 hours.