Injection of hair roots harvested by FUE method into the skin with the help of a pen is called Pen Method (Implanter Pen Technique) or DHI (Direct Hair Implantation). This method has a more painless and faster healing process.
The hair roots taken with the FUE method are inserted into the pins. The doctor adjusts the depth, direction and angle of the pens before injecting the root into the skin. After the needle is withdrawn, the root remains under the skin.
With pens thinner than 1 millimeter, it is possible to transplant without cutting hair and to transplant between areas where there is less hair or between the beard and mustache areas without leaving a mark or incision.
Generally the DHI method is used for women whereas they don’t want to shave their hair.