Structure of nails

[StringJunky]

I don't know the right words  to search google for the fibre orientation and general structure of finger and toenails. All I get is the parts of the nail area when I want to know composition and structure of a nail itself. Any ideas?

Edited August 6, 2017 by StringJunky

[Endy0816]

Do you mean Alpha Keratin or are you looking for something more specific?

[StringJunky]

3 hours ago, Endy0816 said:

Do you mean Alpha Keratin or are you looking for something more specific?

Yes, but what is the physical arrangement of it? Like tubes or rods arranged longitudinally, or stratified horizontally, or homogenous  etc.

Edited August 6, 2017 by StringJunky

[Area54]

Fisrt item on Google Scholar search [nail structure] is  "On the Structure of the Normal Nail".

Abstract

A scanning electron microscopic (SEM) study of cut surfaces in normal human nails have confirmed the previous description of nail structure, i.e. the hard dorsal nail plate supported by the plastic intermediate nail plate.

Unfortunately locate behind paywall - £35.

 

From page 3 of the aforementioned search is this item - "Histological structure of human nail as studied by synchrotron X-ray microdiffraction"

Abstract

Three layers (characterized by different orientations of the keratin molecules) from the outer to the inner side of human nail were observed by synchrotron X-ray microdiffraction. These layers are associated with the histological dorsal, intermediate and ventral plates. The hair-like type alpha-keratin filaments (81 A in diameter), are only present in the intermediate layer (accounting for approximately 2/3 of the nail width) and are perfectly oriented perpendicular to the growth axis, in the nail plane. Keratin filaments of stratum corneum (epidermis) type, found in the dorsal and ventral cells, are oriented in two privileged directions; parallel and perpendicular to the growth axis. This "sandwich" structure in the corneocytes and the strong intercellular junctions, gives the nail high mechanical rigidity and hardness, both in the curvature direction and in the growth direction. Lipid bilayers (49 A thick) parallel to the nail surface fill certain ampullar dilations of the dorsal plate and intercellular spaces in the ventral plate. Using X-ray micro-diffraction, we show that onychomycosis disrupts the keratin structure, probably during the synthesis phase.

[StringJunky]

11 minutes ago, Area54 said:

Fisrt item on Google Scholar search [nail structure] is  "On the Structure of the Normal Nail".

Abstract

A scanning electron microscopic (SEM) study of cut surfaces in normal human nails have confirmed the previous description of nail structure, i.e. the hard dorsal nail plate supported by the plastic intermediate nail plate.

Unfortunately locate behind paywall - £35.

 

From page 3 of the aforementioned search is this item - "Histological structure of human nail as studied by synchrotron X-ray microdiffraction"

Abstract

Three layers (characterized by different orientations of the keratin molecules) from the outer to the inner side of human nail were observed by synchrotron X-ray microdiffraction. These layers are associated with the histological dorsal, intermediate and ventral plates. The hair-like type alpha-keratin filaments (81 A in diameter), are only present in the intermediate layer (accounting for approximately 2/3 of the nail width) and are perfectly oriented perpendicular to the growth axis, in the nail plane. Keratin filaments of stratum corneum (epidermis) type, found in the dorsal and ventral cells, are oriented in two privileged directions; parallel and perpendicular to the growth axis. This "sandwich" structure in the corneocytes and the strong intercellular junctions, gives the nail high mechanical rigidity and hardness, both in the curvature direction and in the growth direction. Lipid bilayers (49 A thick) parallel to the nail surface fill certain ampullar dilations of the dorsal plate and intercellular spaces in the ventral plate. Using X-ray micro-diffraction, we show that onychomycosis disrupts the keratin structure, probably during the synthesis phase.

Perfect. Thank you. I've got some pointers now. I'm trying to understand how nails lose their strength or maintain it which is possibly due to  ingress and egress of moisture and other substances. Having porous or unpolished edges makes them considerably weaker and I'm trying to understand why that is. It's necessary for me to understand the structure first, that's why I asked. I fingerpick my guitar sometimes and I've been working on them to get them in optimal condition.

Edited August 6, 2017 by StringJunky

[Area54]

I'm pleased it was of some use. Maybe even finger-picking good.

[geordief]

On 8/6/2017 at 7:06 AM, StringJunky said:

Perfect. Thank you. I've got some pointers now. I'm trying to understand how nails lose their strength or maintain it which is possibly due to  ingress and egress of moisture and other substances. Having porous or unpolished edges makes them considerably weaker and I'm trying to understand why that is. It's necessary for me to understand the structure first, that's why I asked. I fingerpick my guitar sometimes and I've been working on them to get them in optimal condition.

Metal strings? My nails were never up to that and I basically use my fingertips (I think Mark Knopfler  does too)

As for nylon(gut actually) ,my father played the classical harp and his nails were a wonder to behold .

I once tried eating gelatine but never noticed any difference.

Edited August 7, 2017 by geordief

[StringJunky]

1 minute ago, geordief said:

Metal strings? My nails were never up to that and I basically use my fingertips (I think Mark Knopfler  does too)

As for nylon(gut actually) ,my father played the classical harp and his nails were a wonder to behold .

I once tried eating gelatine but never noticed any difference.

I don't get to play my steel string guitar so much now because my nephew has it most of the time but I've been using a glass nail file regularly the last few months and they are nearly  like horn now. I need wire cutters to snip the thumbnail; my left fretting hand one got too long so I tried to cut it with scissors but failed. My nails used to be very fragile and split at the ends as well being easily chip. I read a while ago that glass files produce a fine dust which apparently seals them; this seems to be the case. It seems, from Area54's link, that there is a porous, more fibrous middle layer. I was wondering, if the nail was filamentous, then loss of moisture, or whatever, caused a loss of rigidity plus ingress of everyday chemicals being absorbed by capillary action attacking the nail structure. My basic idea being that keeping body moisture in and enviromental substances out has made them as strong as they are. My diet has not changed and I do not apply any nail preparations.

Technique is important too in terms of avoiding excessive nail wear and I think some people have them too long, playing wholly on the nail when, as in classical technique, one should tension the skin with flesh but ping the string with nail, using only a modicum of pressure on it. 

[geordief]

Very interesting. I might  have a go myself.

[StringJunky]

33 minutes ago, geordief said:

Very interesting. I might  have a go myself.

I have a Leighton Denny but I've since found Wolfram Files that was designed with guitarists in mind, which might just have a bit better polishing ability. Don't get a cheap one because they are not acid-etched etched but glass particles glued on to glass which wear off and don't give as fine a finish... been there!

Edit to add: I initially wondered if hydrostatic pressure helped keep nails rigid and sealed ends are necessary to maintain it.

Edited August 7, 2017 by StringJunky

[mistermack]

I've tried and failed to improve my nails for finger picking, so this is good stuff and thanks for the pointers.

It sounds like it's a mistake to use the glass file on the left hand though, but I'll definitely be trying it on my right hand.

I've tried all sorts including false nails and various lacquers, nothing really worked for me. I find it odd that some nails are much stronger than others. My little finger nail is by far the best, and it gets the same minerals as the others.

[DrP]

I don't know if this works or if I just have good nails..  I play the guitar too...   on my right hand, my picking hand, I have good strong long nails. They tend to break if they get too long and I engage in manual labour. For decades now I have (and I am sorry if this is disgusting, it is just something I have always done from school) coated my nails from time to time in fluids such as ear wax, scalp oil and tooth plaque even...   I then polish them up with this almost as a sub conscious habit. I use my thumb to polish the other nails.  These days I no longer use the tooth plaque as I find it a bit disgusting (habit I had a school) but still use the ear wax and scalp oil.

I do not know if this has any kind of moisturising or nourishing effect on them, but they don't break easily. I file them myself by scratching on rough surfaces, even rough plastic. The do get quite shiny and smooth after a waxing though.

Regarding technique - I probably pick more with my finger pads and use the nails when I want more attack. I sometimes just use my nails instead of a plectrum or to give a flamenco style strum/flourish.  They probably get used if I am doing tremolo also. I don't really think about it any more.  

[geordief]

11 minutes ago, DrP said:

I don't know if this works or if I just have good nails..  I play the guitar too...   on my right hand, my picking hand, I have good strong long nails. They tend to break if they get too long and I engage in manual labour. For decades now I have (and I am sorry if this is disgusting, it is just something I have always done from school) coated my nails from time to time in fluids such as ear wax, scalp oil and tooth plaque even...   I then polish them up with this almost as a sub conscious habit. I use my thumb to polish the other nails.  These days I no longer use the tooth plaque as I find it a bit disgusting (habit I had a school) but still use the ear wax and scalp oil.

I do not know if this has any kind of moisturising or nourishing effect on them, but they don't break easily. I file them myself by scratching on rough surfaces, even rough plastic. The do get quite shiny and smooth after a waxing though.

Regarding technique - I probably pick more with my finger pads and use the nails when I want more attack. I sometimes just use my nails instead of a plectrum or to give a flamenco style strum/flourish.  They probably get used if I am doing tremolo also. I don't really think about it any more.  

Seems like you inspired the great JH with your tooth  technique (none of my beeswax ,I suppose)

 

Seeing as some of the less commercial moisturizers are also a possibility maybe we have dug deep enough for our craft

[StringJunky]

53 minutes ago, mistermack said:

I've tried and failed to improve my nails for finger picking, so this is good stuff and thanks for the pointers.

It sounds like it's a mistake to use the glass file on the left hand though, but I'll definitely be trying it on my right hand.

I've tried all sorts including false nails and various lacquers, nothing really worked for me. I find it odd that some nails are much stronger than others. My little finger nail is by far the best, and it gets the same minerals as the others.

I would use it on both hands just for general nail care as well.  I just let the left hand nail grow long but decided to take it down to match the the rest on that hand. Once you file and seal all your nails  you may find they are all the same in hardness and rigidity. Just noticed Dr P's post: it might accelerate your goal by using an emollient everyday on the nail surfaces to hold the moisture in but use a buffing block first to polish the surfaces of roughness and ridges and also put a slight round on the top corner edge of the nail ends for a non-scratchy sound. The final objective is to get everything flat and polished to minimise absorption of everyday  liquids/contaminants and egress of natural moisture from inside the nails.

Edited August 8, 2017 by StringJunky