How many micrografts are there per cm2?
The density on the human scalp is 193.75 hairs per square cm or 1250 hairs per square inch. The average human head has 80 square inches to it which translates to 100,000 hairs on a typical Caucasian. Asians have about 80,000 hairs and Africans have about 60,000 hairs. Assuming the average follicular unit has 2 hairs each (typical Caucasian), that would put the numbers at 100 follicular units per square cm in a typical non-balding Caucasian. Doctors can transplant (with modern dense packing techniques) about 50 follicular units per square cm (100 hairs on average) when indicated. Clearly there issues that logically should point to how much coverage can one get. The higher the density, the smaller the area of coverage (assuming supply limitations which are always a factor) In a very bald person, it would be virtually impossible to transplant such high densities to cover the entire balding area as the supply would clearly not meet the needs. So the artistry of the doctor becomes important to maximize the characteristics of the patient’s hair.