On the human scalp, hair grows in form of naturally occuring groupings containing 1, 2, 3 or, rarely, 4 hair follicles each. These groupings are called follicular units. Also reffered to as follicular unit grafts by hair transplant clinics.
In certain locations, like the hairline, the temples and the swirl, nature shows a preponderance of 1 hair follicular units.
While performing a hair transplant, in the refined procedures, care is taken to place the 1 hair grafts in the hairline, temples, centre of the swirl area etc. The multi hair follicular unit grafts are placed in the areas behind the front feathered hairline zone to buit up the density.
Similarly, in the more advanced combination procedures where the scalp grafts are augmented by facial and different body hair grafts, the doctor has to plan the location of the different types of grafts according to the hair's individual characteristics.
