Transplantation density is one of the Key factor for a succesfull hair transplant procedure. Today, the experienced and skilled hair transplant surgeons can achieve great looking hair thanks to the few techniques that lead to high transplantation density. But to achieve that, the hard part is how to determine suffiscient density according to the type of hair that is being transplanted.
On average the natural donor density is between 50 to 90 FU/cm² depending on the lethnicity.
When we transplant, the goal is to reach a density that gives a result that looks as dense as the donor area, no matter how the hair is combed or styled. To achieve this goal it is not usually necessary to transplant with a density as high as the donor. Simply because the human eye can only see the difference when the density is dramatically different.
For example: patient A has a donor density on the temples of 65-70uf/cm², only 45 UF/cm² can be sufficient. Patient B has a donor density on the temples of 55uf/cm² only 40 will be sufficient. the eye will not perceive the difference.
This is an example of an implantation of 55 to 60fu/cm² on a thin hair patient. His donor density is high between 75 and 80.
It is customary to set the felt density frontier around 40fu/cm² for men and 55 for women. this mathematical density is usually sufficient for a perfect result. However, it is important to take into consideration all aspects of your hair to determine the appropriate density. Therefore, it is very hard to determine the perfect density by other means that a direct consultation with a specialist and a microscopic analysis.
To achieve these high density, the technique of lateral slits is the best technique enabling high density of up to 70us/cm². We recommend and only offer surgeons using lateral slits techniques with custom cut blades.
The smaller the incisions, the more the surgeon can implant tightly. It is called dense-packing implantation.
Example of 1977 follicular units transplanted on the frontal hairline.
The incision must be as small as possible whilst sufficiently large for the graft to grow in good conditions. The blood vessels trauma should also be as minimal as possible to enable a good oxygenation of the follicules.
The blade handle fitted with a custom cut-to-size blade for single hair follicular unit.
The angle and the direction of each incision must be defined very precisely. Each Micro-slit determines the direction of growth. Therefore the incision angle must respect the natural direction of the hair.
We have seen that the right type of grafts ( follicular units) and a good incision technique (lateral slits) are the two ingredients to get natural looking transplantation. The last addition is the surgeon artistry which is off course extremely important. Proportions of the face must be respected. A frontal hairline well designed can change a face.
The esthetical criterias go hand in hand with the mathematical factors. The experience and the artistic sense of the surgeons are essential.