Almost every modern hair transplant is follicular unit extraction: individual grafts of one to four hairs are taken from the back and sides of the scalp, where hair is genetically resistant to thinning, and moved to where it has been lost. Sapphire FUE and DHI are both FUE. What differs is the second half of the operation.
- Shared first step
- Follicles extracted individually with a punch, typically 0.7–1.0 mm
- Sapphire FUE
- Channels opened with sapphire-crystal blades, then grafts placed into them
- DHI
- Channel and placement combined in a hollow implanter pen
- Typical session
- Commonly 6–8 hours, usually under local anaesthetic
The part that is the same
Extraction is identical in both. A small cylindrical punch separates each follicular unit from the surrounding tissue and it is lifted out, kept in a holding solution and sorted by the number of hairs it carries. Single-hair units go to the hairline where the transition has to look soft; larger units go behind them where density matters more than detail.
The time grafts spend outside the body matters. They are living tissue, and survival falls the longer they wait, which is why a session is organised around keeping that interval short rather than around the number of grafts a clinic can advertise.
Sapphire FUE: channels first
Here the surgeon opens all the recipient sites first, then places grafts into them. The "sapphire" is the blade material — a crystal blade rather than steel. It holds a finer edge, which allows smaller and more consistent incisions, and smaller incisions mean sites can be placed closer together and heal with less disturbance to the surrounding skin.
The real advantage of opening channels as a separate stage is control. The angle, depth and direction of every site is decided in one continuous pass, and hair direction is most of what makes a result look natural — hair that emerges at the wrong angle reads as a transplant even at perfect density.
DHI: one instrument, two steps
DHI uses an implanter pen — a hollow needle loaded with a single graft. The needle makes the opening and pushes the graft in as it withdraws, so the site never sits empty. Grafts spend less time outside the body, and there is less handling of each one with forceps.
It is generally slower per graft and requires a larger trained team, which is why it is often used for smaller areas, for the hairline, or for adding density between existing hairs, where making an opening beside a hair you must not damage is easier with a pen than with a blade.
What happens afterwards
Days 1–10
Swelling, crusting at each site, and a donor area that feels raw. Washing is done to a specific routine given by the clinic.
Weeks 2–6
Most transplanted hairs shed. This is expected — the follicle stays, the shaft falls. It alarms people who were not warned.
Months 3–6
New growth starts, fine and often lighter than final colour.
Months 9–12
The result becomes a result. Texture and thickness continue to improve after this.
Month 12–18
The point at which a result is fairly judged.
Is it painful?
The procedure is done under local anaesthetic; the injections themselves are the part most people describe as uncomfortable. Afterwards, soreness in the donor area for several days is usual.
Will anyone be able to tell?
In the first two weeks, yes — the sites are visible. By around a month the scalp usually looks unremarkable, and the visible result arrives much later, from three months onwards.
How many grafts will I need?
That is a question for an examination, not a website. It depends on the area to cover, the density of the donor region and the pattern of loss, and a figure quoted before anybody has looked at your scalp is a sales number.
Can I have a transplant if I am still losing hair?
Often yes, but the plan has to account for where the loss is going, not only where it is now. Placing a hairline that will look isolated once the area behind it thins is a well-known way to produce a result that ages badly.