Basic biophysics and bio-engineering

SMP® Knowledgebase

One of the most important set of questions concerning micro-pigmentation about the type of pigments that are used. What are the pigments, how long do they last, and how do they react to light? Below are some of the most common questions potential clients commonly ask with regards to pigmentation.

Explain a quick technical overview of what the SMP process entails?

SMP pigmentation is a process by which a very small shaft comprised of three needles on the end of a pigmentation machine, work together to inject a stable chromophore (pigment) into the second, dermal layer of the skin on the scalp. Pigments are delivered dot by dot over the scalp and the entire process scales with the Norwood level of the client. Typically the dot size is dependent upon practitioner hand pressure and is in the range of 80 to 170 Um (micrometers) at the frontal hairline and 120 to 250 Um at the back apex of the scalp, although this varies with an individuals in utero genetic coding, collagen micro-structure, immune system and recent epigenetic cellular regulation.

Explain what happens when the pigmentation needle machine pierces the scalp?

The three needles will pierce down through the epidermis and into the second layer of the skin below, the dermis. The practitioner will set the needle machine to reach the upper portion of the dermis. Pigmentation molecules will then be deposited in the collagen matrix of the dermis. This matrix is like a basket weaved network of crisscrossing fibers that have open spaces (lumen) within. It is within these lumen, that pockets of pigment will deposit.

What is the size of the needle which pierces the scalp and what is the pain level realistically?

The needle is known as a standard 3 Round and it is actually three steel needles soldered to a base in a circular pattern. This is the smallest standard size needle that is used in large quantities by pigmentation specialists and each individual needle has a base of 450 Um (micrometers) in diameter with a tip of 30 Um in diameter (a red blood cell for comparison is often 6 to 8 Um in diameter and a human egg cell from the female ovary is about 100 Um in diameter) and is under high magnification, a triangular wedge needle at the tip (ie.. it is shaped like a sharp triangle). Artists use the 3 round needle for fine detail work commonly. Under light pressure the needle can make dots about as fine as 80 Um and under very heavy hand pressure from the practitioner, it can make dots up to perhaps 900 Um (or 9/10ths of one millimeter (mm)).

On a pain scale from 1 to 10, with a one representing a minor scratch to ten representing something like a kidney stone or a major burn, most clients rate a SMP treatment overall as a three to five. However, as with any Gaussian sampling curve, some clients will experience SMP as a level 7 pain event and some clients have actually fallen asleep. The most painful areas in general to treat are the areas right above the ears and skin over the temple nerves. The least painful areas to treat are the apex of the scalp and the back crown.

Explain in detail how the pigment is injected?

The 3 Round tip is sent downward into the skin by an electromagnetically inductive circuit. The 3 Round needle ends will bend together as backwards pressure is applied from the resistive skin and pigment will flow to this tip. The needle will break the epidermis and travel about 0.25 to 0.55 millimeters through the epidermis and into the top of the dermis. (this distance is dependent upon the practitioner’s hand pressure and individual’s skin depth structure and can be adjusted). As the needle reaches the dermis, tiny capillaries and blood vessels will be broken by the path of the needle and the wound will bleed a very tiny amount dependent upon the individual. Nerve endings in the dermis will also register the path of the needle as neuropathic pain, with resulting changes to ion channel dynamics. The path of the needle will leave a ‘V’ shaped micro incision. If viewed extremely closely, this V shaped micro-wound will appear as a tiny incision and be about 400 Um wide at the top. Blood and clotting factors will swell up in the wound and some of the pigment will be pushed back up out of the wound.

Why is the pigmentation placed in the middle dermal layer?

In all normal healthy humans, the skin is comprised of three layers; the epidermis on top, the dermis in the middle and the sub-dermis below. The epidermis completely sheds itself every 45 to 50 days, and therefore, placing pigment there would be futile as it would slough off. The middle dermal layer contains a forest of micro collagen fibers that is comprised of strands with spaces (lumen) between them. These open spaces are the areas where the pigment is deposited. Once the client’s immune system responds to the site of the wound and cleans up the loosely held pigment, the more tightly packed pigment molecules in smaller lumen will not by touched by roving macrophages, or the rate of removal becomes so low as to not be measurable.

Does bleeding of the micro-incisions affect the placement of SMP?

Yes. If the client bleeds at an above average rate, pigment will be trapped in the blood and actually move upward with the clotting factors and some pigment will be pushed out of the wound. This is exactly opposite from the goal of trying to retain as much pigment as possible in the dermis. This means that more than the average number of treatments can sometimes be needed to achieve the appropriate SMP darkness shades on the scalp. Although, rate of bleeding is dependent upon an individual’s genetics and blood pressure, some clients have reported that eating certain legumes or spinach for ten days before a treatment, can lower bleeding rates significantly.

How does the incision begin to heal?

Hemostasis, the cessation of blood loss and closing of the micro-wound begins immediately when underlying collagen is exposed to platelets in blood plasma, and initiates biochemical changes within the blood platelets cytosol. The plasma protein fibrinogen is then affected and platelets then begin to form a physical plug at the wound site. Coagulation factors in blood plasma also respond in a biochemical amplification feedback circuit to form fibrin strands (this is secondary hemostasis). This adds anisotropic strength to the platelet plug. A soft scab is formed at the site usually within 30 minutes and this is hardened by additional fibrin over the next several hours. This scab will then remain as fibroblasts fill in weakened areas under the scab within 48 hours and endothelial cells migrate to the site in a complex cascade. As this process completes, the scab falls away, usually within three to seven days.

Why do the pigment dots appear so large during the first 4 to 10 days?

Immediately after a treatment, the scalp will be covered in hundreds of small pigment filled scabs, which is what is seen in many after photos. These scabs are often 400 to 800 micrometers across and far larger than the eventual SMP ‘dot’ will be (the pigment trapped in the collagen below). These scabs flake away in the first four to ten days and the body’s immune system also removes excess pigment caught in the healing wounds during the first three weeks. As this happens, it appears to the client or an observer that the SMP dots are shrinking. When these processes complete, the final dots are often 80 to 170 Um in diameter and blend seamlessly into any natural hair.

How big will the SMP pigment globules trapped in the collagen appear to be when the scalp fully heals?

In an average healthy male with a normal immune system and no special allergies, the dots will often be 80 to 170 Um (micrometers) in diameter. To put this in perspective, the average diameter of a normal hair taken from a caucasian scalp is 77 Um, from a person of Asian descent it is 66 Um and from a person of African descent, it is 120 Um. There are no specific micro mechanical limitations to current pigmentation needle machines using specialized needles (such as carbon fiber) which could indeed be used to place pigment ‘dots’ that are smaller. The problem with this would be that smaller dots laying under the epidermis, in the dermis would then be to small to be noticed by an observer’s eye from one meter away or further. At an average size of 80 to 250 Um, the pigmentation dots need to be large enough to not be fully removed by roving macrophages and also large enough to show through the epidermis as distinct dark dots that mimic actual shaved hair follicles.

Be weary of providers who promise proprietary needle sizes that can lay down dots smaller than 80 Um. This may indeed be true, but by the time the immune response has finished, the dot may be reduced in size to 30 or 40 Um, which it is then very difficult for the client’s eyes or an outside observer to notice. That is the exact reason why HIS aims to place dots that are ideally 150 Um in diameter and are then reduced by the immune and wound healing responses to about 110 Um.

What conditions affect the size of the pigmentation dots ?

Practitioner hand pressure, bleeding and immune system response. If the practitioner places light pressure on the pigmentation needle machine, the dot will be small. If the hand pressure is higher, the dot will be larger. If the client bleeds heavily, then the pigment will be mixed in the blood and be pushed back out of the wound. If the client bleeds very lightly, then more pigment is retained in the micro incision. Macrophages and phagocytic cells in the dermis also play a major roll in the pigmentation process as they act like street cleaning machines to remove foreign debris and pigmentation in the skin. If the client has a heightened immune response, more of the pigment will be removed during the initial wound healing process. This is the primary factor that accounts for apparent fading clients notice two to ten weeks after any treatment, and is highly individual specific.

What conditions affect the long term fading of any micro-pigmentation treatment?

The three most important are ultraviolet radiation exposure (sunlight), long term immune responses and individual dermal collagen micro structure (which is primarily in utero genetic coded but modulated by some epigenetic regulation).

Radiation in the 285 to 400 nanometer wavelength range has the potential to break covalent bonds. Just as two friends holding hands in the ocean can have their grasp broken by a large incoming wave, the same is true for covalent chemical bonds in human tissue and in inks, dyes and pigments. SMP is a pigment molecule (chromophore) which if subjected to long term ultraviolet radiation exposure will indeed breakdown. This can shorten the life of the SMP pigments in the scalp considerably resulting in an apparent fading. Instead of SMP lasting for 8 to 15 years, the treatment efficacy could be reduced to as little as two or three years. This is why sunscreen is a must when working outside for longer than ten minutes or visiting the beach, etc…

Long term immune response is entirely dependent upon the unique biochemistry endowed to each individual. Some people heal from a wound in two to three days while others take weeks or longer to heal from a minor scab. This immune response manifests itself at the micro-level through macrophages and phagocytic cells whose job is to remove foreign debris, particulate and antigens. SMP pigment molecules are seen by these defender cells as foreign material and removed from larger lumen within the dermis. In some clients, this immune response is very strong and after each treatment session, the result is that there is a large apparent fading. In others, this response is much more muted, and a larger percentage of the SMP pigment is retained in the collagen micro structure of the dermis.

The individual structure of the skin and its collagen which is also specific from individual to individual, is also a major factor in SMP pigment retention and fade resistance. Some clients simply have ‘loose’ skin. That means their internal lumen spaces are larger, the collagen micro-structure is not as tight and any pigment deposited will diffuse out and be more easily removed by the immune system. Other clients have extremely tight skin which holds SMP wonderfully and this means that the treatment will last for many more years than a client with looser skin. Unfortunately, measuring or predicting skin tightness is a very inexact process and is not that reliable. For this reason, the ability of a client’s skin to hold SMP can vary considerably.

What is the exact molecular structure of the SMP pigment?

This is a proprietary business secret that we will not disclose at this time as it is an integral part of the HIS business model and is key to making sure that our pigments retain a true gray scale, even under UV degradation. Many other competitors use regular tattoo inks which unfortunately, appear truly black to gray for the first several months, only to begin breaking down at a later date to something more resembling a darker shade of blue or green.

Why is the exact molecular structure of the pigment so important?

The exact nature and alignment of the various chemical bonds in a pigment’s three dimensional structure determine its ability undergo chemical reactions or degrade under UV radiation. Different classes of compounds, such as polymers, metal oxides, proteins, and even lipid based pigments all have unique chemical interactions. Thus, the perfect pigment for a hair simulation application is one that inert, chemically unreactive under most biochemical changes and heavily resistant to UV radiation. While SMP pigments are not perfect, and do in fact degrade over time if subjected to UV radiation, they are normally inert compounds which retain their color even when broken down by intense sunlight. Because of this, SMP will (and does) fade as the decades pass, but it does not change color.

Describe the difference between scar tissue and regular skin with regards to SMP pigmentation?

After a major incision, skin tissue will heal with an underlying collagen network that is aligned in the direction perpendicular to the sheer forces on the newly formed scar tissue. The alignment of collagen strands will be in one direction (isotropic) and will not retain the strength of regular collagen which is aligned in various X-Y-Z directions in an anisotropic manner, which greatly adds structural strength. Also, the collagen networks that reform in the scar tissue, will not retain the tight packing that is common in undamaged skin. This means that internal lumen are often larger and contain unidirectional channels for pigment molecules to diffuse along.

Because of these factors, placing SMP pigment into scar tissue is a more difficult proposition. The rate and manner in which a hair transplant scar can be camouflaged for example, can be very difficult to predict. Each scar is unique and even two scars on the same scalp that are only a centimeter apart can respond to SMP in very different manners. For these reasons, application of SMP to scars is both more difficult or more inexact.

What is technically important about hats in relation to SMP?

In the first twelve hours after a treatment, wearing a hat is probably a good idea, and a baseball cap is also appropriate. This prevents dirt, debris or particulate in the air from falling on the still healing micro-incisions on the scalp. After this first 12 to 18 hours, it is actually preferable to not wear a hat. That is because a hat will put sheer pressure on the healing scabs and the client runs the risk of pulling those scabs off early, taking SMP pigmentation with them. For this reason and possible infection, hats, including baseball caps are not recommended during the healing phase and should first be used about seven days after any treatment.

What is technically important about SMP pigmentation and certain magnetic medical imaging scanning devices?

Scanning a patient’s body in a non-invasive manner to acquire diagnostic data is now a preferred treatment option for hundreds of millions of people worldwide. In addition to ultrasound (which does not use magnetic fields), one of the most popular methods is magnetic resonance imaging (MRI). In order for MRI to create accurate images, a very large magnetic field is employed which is often 10,000 to 200,000 times more powerful than the normal magnetic field on earth. This field is so powerful that any metal devices or substance which contains metallic compounds (like older tattoo inks) can be attracted and pulled on by the large magnetic field. This attraction of an object in the skin, can release both kinetic energy and directional forces as the magnetic attraction attempts to move the object through the skin. This means that in some very old tattoos which contain metallic compounds, there can actually be a burning sensation. However, with SMP pigments, this risk is neutralized by both the amount of pigment in the dermis and the molecular structure of the pigments themselves. While it is always a good idea to explain your past SMP treatments to any medical imaging specialists, MRI technicians or radiologists, we feel the chance for adverse reactions will basically be zero.

What is technically important about MHT and most over the counter skin lotions?

The risk for unknown long term reactions with SMP. HIS does not have the laboratory facilities or budget to conduct hundreds of chemical assays in order to test most over the counter products for their interaction with SMP pigments. While we believe that many over the counter products will be fine for day to day use, we ask clients to shy away from harsher shampoos, soaps and skin lotions, especially if used daily. Prior clients have found good success with matte lotions like L’Oreal Pure and Matte for Men and Headblade Headlube Matte. While we feel these products are fairly safe, we cannot be one hundred percent certain. For this reason, we will not be held liable for detrimental reactions with third party products.

What is technically important about Proactive products and many other facial washes used to treat acne?

Proactive skin products which are used to treat mild to moderate acne contain benzoyl peroxide. Peroxides are bleaching agents and while they decrease bacterial counts, they could be potentially damaging to SMP pigments. Normally agents on the epidermis do not have large effects on substances in the dermis, but peroxides are powerful free radicals. On the skin, Proactiv decomposes to benzoic acid and oxygen but the process is exergonic (Gibbs Free Energy < 0) which means that its effect on SMP would be difficult to determine in the long run with detailed chemical assays. For this reason, we ask Proactiv users to avoid areas of the scalp where SMP pigments are located, as you may experience faster than normal fading if not careful.

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