Hi there, I am hoping for some help with answers to a few questions, especially from hair restoration doctors on the forum.
I was recently reading a past post in which Dr. Sharon Keene showed that in “normal” men without male pattern baldness, the average follicular unit hair density at the front hairline was 51 FU/cm2 with a range of 38-78. And the average density in the temple apex region (behind the recession) was around 44 FU/cm2 with a range of 25-64. From other readings I read that the average hair density in Caucasian males is 100grafts per cm2.
Now when transplanting the frontal 2/3 of the scalp measuring on average 100cm2, it has been recommended that the leading edge/transition zone is all singles of varying density (about 2cm wide), then 1's and 2's closely placed together in the defined zone (2 cm wide), followed by 2's, 3’s and 4's into the frontal core to prevent a see through look/block light. Further the depth of the transition zone in the frontal hairline should generally be about 2cm at the midline and slightly greater towards the temples. Now the frontal transition zone 2cm in depth is on average made up of 500-600 one hair grafts which are soft and irregular forming the very edge of the front hairline, and then switches to 2-hair grafts fairly quickly as soon as you get 2-3 grafts deep into the defined zone which is more defined and dense.




My question is what is the “average” density of hair transplanted at the transition zone, defined zone and frontal core? And what is the natural density of these regions?

Theoretically wouldn’t an “average” male with a mature high hairline and a density of 50 at the transition zone and 40 at the temple region, 55 at the defined zone and 65 grafts per cm2 after that produce a natural non see through look?
And if there is say 100cm2 of scalp or frontal 2/3 to cover wouldn’t the transition zone at 50cm2 density taking up the first 2cm back and then the defined zone at 55cm2 going another 2cm back, wouldn’t that significantly decrease the area of scalp left to cover at the higher core density of 65cm2? Now if the transition zone took away say 500 one hair grafts and the defined zone 550 two hair grafts, and the length of the bald region had a width of 10 cm on the man’s scalp and a length 10cm back, wouldn’t that only leave 60cm2 of bald scalp to cover with a density of 65cm2? Taking 3900grafts plus the 1050 means that only 4950 grafts has been used for a natural near flawless frontal 2/3 of the hair restoration and leaving 2050 for the crown if that goes on the average man with a donor supply of 7000grafts. Is this right? Cheers

Interesting subject. I've often thought that it would be worthwhile to put together a set of photos of hairlines of men without any hair loss. They'd be great for comparison purposes.

For anyone who might have missed Dr. Keene's study, here is her blog where it can be found.

http://www.hairrestore.com/blog/

The man in the first photo does appear to me to have some recession at the hairline.

Thanks mattj, I find it interesting that the crown is also of less density, making a great case for layering, so that if the core density was 65grafts cm2 then the crown may only be 55 or 45 grafts per cm2 thereby saving more grafts and justifying the dense packing.

Implicit with these findings is the question why would some practices dense pack the leading edge or crown at densities of 70 grafts per cm2 and above?

I agree that this is such an interesting topic. I really wish a study could be done like Dr Keane's on mass scale that would measure the average FU's across the different areas of a non-balding scalp.

I remember reading on Dr. Rassman's blog that he said that hair density is evenly distributed across the scalp.....but I have read elsewhere that this is simply not true (see Dr. Keane's study and references within to see what I mean).

To me, by far the most interesting thing about Dr. Keane's preliminary findings is that the 50% we thought we were transplanting might be closer to 100%, which would explain why the human eye apparently cannot distinguish between 50% and 100% density.

Put another way: her study puts average hairline density at about 50'ish FUs......where before we thought it was higher, thus we thought that 50'ish FUs was about 50% when in fact it could be closer to 100%.

The thing with averages is that they represent a middle point in a spectrum. Look at Rob Patinson (dude from Twilight).....his density is clearly at the high end......but you don't need that density to not appear bald, which is really what us baldies want to achieve.

at firat I was letdown to hear that my doc trasplanted only 35 to 40 FU at the hairline.......but now am happy after reading this study.....and have made coverage, not density my main goal, esp when you take Thana's hair routine into consideration.

I would love to hear Dr. Rassman's opinions on this post. The crown in people even with no mpb is often visibly thinner, though angulation may have something to do with this; layering is starting to make more and more sense to me. Cheers

Look at where the small, square centimetres are in the photo. They're right at the very front of the hairline where the hair peters out, and the man in the photos doesn't look like he has a totally intact hairline. I would imagine that men with the kind of perfect, thick heads of hair that many of us hold up as ideal have considerably higher average densities. The mean age of men in the study was 41. The FU/cm2 range was 38-78 at the hairline. The younger men involved probably had densities at the higher end of the range, but also in those cases remember where the areas of study were - at the very front of the hairline.

I'd be interested in a study of density, say, 1cm back into the hairline.

Also remember that singles are generally placed at the front of a transplanted hairline. In nature they are more often grouped.

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Also remember that singles are generally placed at the front of a transplanted hairline. In nature they are more often grouped.

Matt could you please enlighten me more on the above quote. Cheers

Well, to create a softer hairline single hairs are usually placed at the very front, with the groups of 2 to 4 hairs used further back where the increased density is welcome. I don't think nature does this. You'll find follicular units containing the full range of hairs at any point on the scalp.

My own hairline is thin, and I can see groupings of hairs in there which kind of give an appearance that would be considered 'pluggy' if it were the result of a transplant. They only look 'pluggy' because of the reduced density at my hairline. If they were surrounded by more hair they would blend in. I believe the larger follicular groups are considered unsuitable for the very front of a hairline because the transplant generally won't give 100% density, causing these groupings to stand out - as they do on my thin but natural hairline - like saplings among reeds.

That's just been my observation. I don't see this sort of thing discussed very often and if anyone disagrees they should speak up.

quote:

I don't think nature does this. You'll find follicular units containing the full range of hairs at any point on the scalp.

Thanks Matt, this is worrisome to me as I have so often heard that the mimicking of nature is key to great results. If there are more hairs in each follicular unit then it would seem to validate the packing of the transition zone at say 70 grafts per cm2 using singles. I know donor hair is not as soft, being greater in caliber than those at the hairline naturally, maybe justifying combining it with body hair at the hairline, as I know bloke on another forum did with leg hair to achieve a natural result. Cheers

Does anyone have any idea what the natural density of hair is for women? Is it similar for both sexes, or is female density naturally higher?

Thanks!

Hi Liz I really couldn't find too much on the natural density of female hair, but I think I remember reading somewhere that a females' hair in the hair line is finer and softer than that of males. Also I am assuming that it would vary between races as it does with males. Hopefully a doctor might relieve our density perplexity. Cheers

Liz P., interesting question. You might want to start a new thread with your question. That might attract the attention of doctors and informed patients and you might get more responses to your question.