Every patient has a finite scalp donor supply. Once it is exhausted — through advanced hair loss, previous over-harvesting, or several prior procedures — conventional transplantation has nothing left to move. BHT answers that by treating the beard, chest, abdomen, back and legs as a secondary donor reserve, harvested using the same FUE punch technique.
Beard hair is by far the most valuable of these. It is thick, grows densely under the jaw and neck, and yields grafts of a calibre that adds real visual bulk. Chest and body hair are finer and grow in shorter cycles, which makes them better suited to blending, filling and adding background density than to building a hairline.
Body hair behaves differently from scalp hair once transplanted. It keeps some of its original growth cycle, so it tends to reach a shorter maximum length, and its texture and curl may differ. For that reason BHT is almost always used as a supplement to scalp grafts, placed where the difference is least visible — the crown, mid-scalp and behind the frontal zone.