This Follica pdf is really interesting stuff.2. The first three clinical studies Follica did used no topical drug at all; just wounding, and it produced hair follicles.
From FOL-002
Treamement:
Dermabrasion [DA] device (diamond fraise - disruption
depth ~100- 150 microns) and 3 laser type of ablative lasers;
No topical drug treatment
Conclusions:
"DA Creates a Substantial Number
of Hair Follicle Structures of
Interest"
Wounding alone does grow hair, but as per the follica studies; the results require drugs to maintain.