Exposing the 200-300 Times Proportional Inaccuracy in PMU...

Videos

Powder Brows

Procedure, Techniques, Pigments, Aftercare...

Microblading

Procedure, Technique, Patterns, Supplies, Retention...

Ombre Brows

Soft Ombre, Pixels, Whip, Pendulum techniques...

Hairstrokes

Nano Brows, Hairstrokes patterns, Natural PMU...

Combo Brows

Powder + Miroblading, Powder + Hairstrokes...

Marketing

Instagram, Facebook, TikTok, Organic growth...

Removal

Saline, Lactic Acid, Laser removal procedure...

Articles

Powder Brows

Procedure, Techniques, Pigments, Aftercare...

Microblading

Procedure, Technique, Patterns, Supplies, Retention...

Ombre Brows

Soft Ombre, Pixels, Whip, Pendulum techniques...

Hairstrokes

Nano Brows, Hairstrokes patterns, Cashmiere...

Getting started

Starting artist adivce, practical first steps...

Marketing

Offline marketing, Online marketing, website, domains...

Practical Tips

Guides, Tips, Suggestions, Walkthroughs, Case studies...

Removal

Saline, Lactic Acid, Laser removal procedure...

Tops Pricing

1. Research and Expert Reviews

Many professional artists have pointed out the problem of inaccuracy in training materials that they have encountered, which concerns, more specifically, the proportions and thicknesses of the skin layers. This analysis is grounded in comprehensive research, drawing on interviews with 49 professional pigmentation artists. These interviews were conducted as part of various research projects initiated in 2019 and are still ongoing. The majority of these artists, 38 in total, are based in the European Union, with six from the United Kingdom and five from the United States.

To ensure accuracy and scientific validity, the material compiled for this article underwent a thorough review process. Two experienced dermatologists and an expert specializing in cellular biology provided their insights and feedback. Significantly, the empirical experiences of these professional artists lend further support to the conclusions presented in this analysis, reinforcing the real-world applicability and relevance of our findings.

2. The Structure of the Argument

We begin by discussing how many pigmentation trainers illustrate the layers of the skin, focusing on the relationship between the epidermis, dermis, and a typical pigmentation needle. This needle often enters and, in most cases, pierces through the epidermis. We then examine the proportional measurements that show the relationship between the needle's diameter and the thickness of the epidermis in such cross-sections.

Next, we provide scientifically accurate measurements of human skin layer thicknesses in the facial area, including a significant margin of error and specifically considering the skin in the brow area. This gives us a crucial range for the thickness of the epidermis. We then compare this to the thickness of a typical 1 RL 0.3 needle with a medium taper, approximately 1.5mm, to determine the actual ratio of needle diameter to epidermis thickness.

Finally, to synthesize these ideas, we aim to present a comprehensive understanding of this phenomenon. Our goal is to offer practical insights for artists working in the field of semi-permanent pigmentation, enhancing their understanding of skin and needle interactions. We also offer a possible explanation of the origin of such misleading graphics based on the scientific material available.

3. Mistakes in Training Materials

Examining Inaccuracies in PMU Training Materials

We have analyzed cross-section drawings and graphics from five different training materials to explore this issue. These materials are used in courses teaching powder brows, microblading, and hairstroke techniques. Each training provider has been active in the market for at least five years, establishing them as reputable sources in the field.

We investigated the backgrounds of the academies that utilize and distribute these materials to their students. Our research indicates that these academies and trainers are not novices; they can offer quality training. While the overall quality of the programs varies, they generally provide largely accurate information.

Analysis of Cross-Section Images in PMU Training Materials

We conducted an in-depth analysis of 12 cross-section images obtained from the training materials of the five aforementioned academies. Our focus was on three key criteria in each image:

Needle Thickness vs. Epidermis Thickness. We evaluated how the thickness of the depicted needle compares to the thickness of the epidermis in the images. This comparison is crucial to understanding the scale and impact of needle penetration on the epidermis.
Epidermis vs. Dermis Thickness. We examined the relative thickness of the epidermis compared to the dermis. This aspect helps assess the accuracy of the skin structure representation in these materials.
Needle Length about Skin Layers. We analyzed the needle length and the thickness of the dermis and epidermis. This criterion is important to understand the depth of needle penetration during PMU procedures as depicted in these training resources.

Limitations in Depicting Dermis Thickness

In our analysis, we noted that many of the drawings were overly simplified, making it challenging to determine if the full thickness of the dermis was accurately depicted. Therefore, we included only those cross-section graphics showing the boundary between the dermis and hypodermis. It's important to acknowledge, however, that any proportional inaccuracies in depicting the thickness of the dermis compared to the epidermis do not significantly impact our primary focus, which is the comparison of needle diameter against epidermis thickness. Thus, these potential discrepancies are considered secondary information.

Drawings vs. Microscope Photos

Another crucial aspect to consider is the purpose of medical and popular science graphics. Often, these drawings emphasize the internal elements of the skin rather than accurate proportions. Consequently, when pigmentation trainers use such graphics at face value to create images incorporating needles, it can lead to significant misunderstandings. In contrast, actual microscope photos provide a much clearer understanding of skin layer's proportional differences and thickness than typical needle diameters. However, acquiring and accurately interpreting these photos requires specialized dermatology, biology, and anatomy knowledge.

4. Graphics in PMU Training Materials

A stop sign and a thin needle penetrating a manifold thicker surface on the left.

Depiction of Needle and Skin Interaction

In most of the graphics we analyzed, the needle cartridge is positioned above the skin, with the needle extending downwards, penetrating the epidermis. Typically, these images depict the needle as emerging significantly from the cartridge and entering the epidermis. Our analysis of three materials showed the needle piercing through the epidermis and reaching into the upper part of the dermis. In one material, the needle is illustrated as stopping at the very bottom of the epidermis, while another material shows the needle penetrating the basal membrane of the epidermis.

Measured Proportions in the Graphics

Our analysis focused on the depicted diameter of the needle relative to the thickness of the epidermis. We found that in these illustrations, the epidermis was often shown to be 30-50 times thicker than the diameter of the needle. This portrayal creates a visual where a relatively long and slender needle pierces a skin layer that is, on average, over 40 times thicker than the needle's diameter.

5. The reality

How Are Skin Layer Thicknesses Measured?

Measuring the thickness of the epidermis, particularly in the facial area, involves precise techniques and specialized equipment. We outline several commonly used methods:

Biopsy and Histological Analysis

Procedure. A small skin biopsy is taken from the facial area under local anesthesia.
Analysis. The skin sample is processed and stained for histological examination, allowing distinct visualization of skin layers, including the epidermis, under a microscope.
Measurement. A micrometer measures Epidermis thickness from the top of the stratum corneum to the basal layer.

Ultrasound Imaging

Technique. A non-invasive method using high-frequency sound waves to image skin layers.
Procedure. An ultrasound probe is applied to the skin to create images of the skin layers.
Analysis. The epidermis is identified as a distinct layer, and its thickness is measured from the ultrasound images.

Optical Coherence Tomography (OCT)

Principle. A non-invasive imaging test that uses light waves to produce cross-section pictures of the skin.
Procedure. A handheld device emits and captures light waves, creating detailed images of the skin layers.
Measurement. Specialized software measures the epidermis thickness from these images.

Confocal Laser Scanning Microscopy

Technique. A non-invasive method that uses laser light to obtain serial optical sections of the skin.
Procedure. Laser scans the skin, creating detailed images of the skin's microstructure.
Analysis. Enables visualization and measurement of the epidermis layer without physical biopsies.

Considerations in Measurement

Accuracy. Histological analysis is the gold standard but invasive.
Variability. Skin thickness varies based on location, age, gender, and health, requiring multiple measurements for accuracy.
Ethical and Practical Aspects. In non-research settings, non-invasive methods like ultrasound, OCT, and confocal microscopy are preferred for safety and practicality. In clinical or research settings, the choice of method depends on accuracy needs and the procedure's feasibility.

6. Dermis Thickness in the Brow Area

The thickness of the dermis varies across different parts of the body and is influenced by factors such as age, gender, ethnicity, and overall health. While there may not be universally standardized measurements specifically for the brow area, we can infer its thickness based on general scientific knowledge about the facial dermis.

Variation in Brow Area

At Brow's Start. Near the beginning of the brow, the dermis can be relatively thick, possibly exceeding 1 mm (1000 micrometers or 1 million nanometers).
Range. Depending on individual factors like skin type, health, and ethnic background, this thickness may vary between 1000-2000 micrometers (1-2mm).
Towards the Tail. The thickness decreases significantly as we move towards the brow's tail.

Considerations in Dermatological Literature

It's important to note that such specific measurements for the brow area are less commonly detailed in dermatological literature. Most references to dermal thickness relate to broader facial regions rather than specific areas like the eyebrows. However, for the purpose of our analysis, we can use the data about the “healthier and thicker” version of the dermis. This approach still allows us to draw valid conclusions relevant to our study.

Epidermis Thickness in the Eyebrow Area

The epidermis in the eyebrow area exhibits less thickness variation than other skin areas. Considering the diversity of skin properties, the thickness of the epidermis in this region is typically within the range of 50-100 micrometers (0.05-0.1 mm).

Consistency with Dermatological Knowledge. This range is consistent with established dermatological understanding. The epidermis, being the outermost skin layer, is significantly thinner than the underlying dermis.
Variation Across the Body. While there is some variation in epidermis thickness across different body areas, it is generally less pronounced than in the dermis.
Comparison with Other Body Parts. The facial epidermis, including that of the brow area, is typically thinner than in areas subjected to more mechanical stress, like the palms of the hands or the soles of the feet.

Understanding this is important when we discuss the differences of the "Thin skin" and the "Thick skin", in the latter sections of this article, explaining what may be the source of the incorrect graphic used in training materials.

Needle Diameter vs. Epidermal Depth Analysis

For our analysis, we selected a 1 RL 0,3 needle with a medium taper as an example. The taper length of this needle typically ranges from 1.5-2mm, varying slightly among different manufacturers.

Penetration Depth and Resulting Wound Diameter

Half Taper Penetration: When this needle penetrates the skin to a depth of half its taper length, the diameter of the resulting circular wound is about 150,000 nanometers (150 micrometers or 0.15 mm).

Full Taper Penetration

Conversely, if we replicate a similar cross-section image as used in the analyzed training materials, where the needle penetrates with its full diameter, the diameter of the wound would be the entire 300,000 nanometers (300 micrometers or 0.3 mm).

7. The real proportions

A woman smiles, showing a peace sign, and a large needle penetrates a thin surface on the left.

Graphics Representation: The training materials tend to depict the needle entering the skin at its full diameter, which is 300,000 nm. This visualization can significantly differ from the actual wound created by a needle entering at half its taper length.

Actual Hole Made in the Epidermis by the Needle

The diameter of the hole created by the needle in semi-permanent makeup procedures is considerably larger than the depth of the epidermis in the brow area. The epidermal thickness in this region typically ranges from 50,000 to 100,000 nanometers (0.05 to 0.1 mm). This discrepancy indicates that commonly used graphics in semi-permanent makeup training often misrepresent the relative thickness of the epidermis, portraying it as thicker than its actual size.

Epidermis Resistance to Needle Penetration

Despite its relative thinness, the epidermis, and specifically the Stratum Corneum, is crucial in providing resistance to needle penetration. The Stratum Corneum, often referred to as the "Horny Layer," possesses a tough structure akin to an animal's horn. This toughness is a significant factor in the skin's defense against mechanical intrusion, such as needle penetration in semi-permanent makeup applications.

8. Conclusions about errors

Our analysis leads to a critical conclusion regarding depicting skin layers in semi-permanent makeup training materials. When accurately representing a cross-section of facial skin layers, the epidermis should be shown as being approximately 3-6 times thinner than the diameter of a typical needle used in pigmentation procedures. This finding challenges the accuracy of images commonly used in training materials. Even when considering individuals with the thickest epidermis and the thinnest needles, the proportions depicted in these materials are significantly off from reality.

This discrepancy highlights the need for a more realistic portrayal of skin structure in training materials. Accurate representations are essential for practitioners to understand their work's true scale and impact, ensuring both the effectiveness and safety of semi-permanent makeup procedures.

The Extent of Misrepresentation in Graphics

When analyzing the training materials, a startling discrepancy becomes evident. The needle diameter to epidermis ratio depicted in these materials is approximately 1:50, whereas the actual, accurate ratio is closer to 5:1. This means that the graphics in these training materials are off by a factor of 250 times! The implications of this are significant, especially for beginners in the field.

Consequences for Starting Artists

Such a drastic misrepresentation leads to a false perception among starting artists that the epidermis is much thicker than it actually is. This misconception may encourage them to insert the needle deeper than necessary, under the assumption that there is ample "room" within the epidermis. Unfortunately, this often results in the pigment being implanted too deep, sometimes even reaching the hypodermis. This incorrect depth of pigment placement can lead to pigment migration, a phenomenon commonly known as a “blowout.”

Empirical Support from Professional Artists

The notion that the epidermis is considerably thinner than often portrayed in training materials is not just a theoretical conclusion. The experiences of many professional artists in the field of semi-permanent makeup also support it. These professionals confirm that, in reality, the epidermis is much thinner than depicted, making it quite easy to reach the dermis during procedures unintentionally.

Visualizing Epidermis Thickness

To visualize the actual thinness of the epidermis, especially in the facial area, one can compare it to the thickness of a sheet of paper. This analogy helps underscore how delicate and thin the epidermis layer really is, contrasting sharply with the exaggerated depictions in some training graphics. This understanding is crucial for practitioners, particularly those new to the field, to avoid excessively deep pigment implantation and potential complications.

A Fascinating Sidenote (For Those Who Appreciate Humor)

If the graphics we've discussed were accurate, and we accepted their depiction of epidermal thickness as true, a typical pigmentation artist would be as tiny as a grain of rice or a pea. This minuscule artist would be dwarfed by a standard paperclip, which measures about 3-4 centimeters in length. If they retained human proportions at this scale, everything would need to be dramatically downscaled, including organs and skeletal structures.

In this tiny world, everyday objects would appear colossal. A simple pencil or a coin would become massive and unwieldy. The physical properties of materials, like surface tension and air resistance, would pose unique challenges. Even insects, often similar in size or larger, could present significant threats, viewing such a diminutive human as prey or danger. Vulnerable to creatures like ants, spiders, or wasps, this person would struggle both for safety and self-defense.

Living in this proportionally altered reality would necessitate a completely customized environment. Everything from clothing to tools would need to be uniquely crafted. Nutritional needs would differ drastically in terms of quantity and consumption methods.

While this is a highly theoretical and imaginative scenario, it is an intriguing exploration of scale and how size influences interactions with our environment. Of course, in reality, the principles of human anatomy and physiology render such a size implausible for a human being, but this thought experiment is valuable for understanding the importance of accurate scale representation.

9. Implantation into Basal Membrane

Additional typical errors in training materials

Many training materials contained three more errors that should be addressed in this context: “Pigment implantation into basal membrane,” “Sweet spot theory”, and “Epidermis thickness and resistance theory”.

This approach incorrectly suggests that pigmentation can be done "into the Basal" membrane between the epidermis and dermis. However, it's important to understand that the basal membrane is considered a part of the epidermis, and it is dermatologically impractical to implant pigment particles precisely into this layer.

Basal Membrane Thicknes

The basal membrane, or the basement membrane, is a thin, fibrous structure that separates the epidermis from the dermis. It's integral to various cellular processes, including adhesion and signaling. This membrane is extremely thin, measuring 10-50 nanometers (0.01-0.05 micrometers), about 0.00001 to 0.00005 mm in millimeters.

Size of Pigment Particles in Pigmentation

Pigment particles used in tattoo inks and similar substances typically range from 100-500 nanometers. This size is chosen to balance their ease of insertion into the skin while ensuring retention within the dermis, avoiding removal by the immune system. Van der Waals forces also influence the behavior of these particles.

Conclusion on Implantation Depth

Considering the size of pigment particles and the basal membrane's thickness, depositing pigment solely into the basal membrane is anatomically unfeasible in both microblading and semi-permanent pigmentation. In microblading, blade incisions penetrate through the epidermis, basal membrane, and into the upper layers of the dermis, particularly the papillary dermis. The same penetration depth is observed with the needle used in semi-permanent pigmentation. This depth ensures that the pigment, whether individual particles or aggregates, is securely implanted within the dermis.

In both microblading and semi-permanent pigmentation, it's also likely that the pigment is implanted into all layers of the dermis, and in many cases, the hypodermis is reached.

10. Hitting the “Sweet Spot” theory

The concept of targeting a “sweet spot” in the papillary dermis is a prevalent myth in pigmentation techniques, including microblading, powder brows, and Hairstrokes. Understanding this theory requires an appreciation of the dermatological, physical, and biological constraints, particularly the skin layers' thinness.

Epidermis Thickness Revisited

As previously noted, the epidermis in the brow area typically measures between 50-100 micrometers (0.05-0.1 mm), being considerably thinner than the dermis. This is especially true for the facial epidermis, including the brow area, which is thinner than areas subjected to more wear, like palms or soles.

Conclusions about the “Sweet Spot”

While theoretically, implanting pigment into the papillary dermis could be dermatologically sound, practically achieving this level of precision is challenging. The practitioner must accurately insert the needle or blade to a depth of approximately 0.2-0.5 millimeters, varying across different brow parts.

Analysis of Implantation Possibility into the “Sweet Spot”

The theory assumes a level of precision in needle penetration that is difficult to achieve in practice. Human senses, such as sight, cannot reliably discern such minute differences in depth. Even though the human eye can detect differences as small as 0.1 mm, visually gauging needle depth during rapid penetration is impractical. Other senses, like hearing the needle prick or feeling its vibration, also fall short in providing the necessary precision. While one might sense the needle piercing the epidermis, differentiating between the depths of the papillary and reticular dermis is beyond our sensory capabilities. As a result, pigment deposition often inadvertently extends into both layers.

Furthermore, both experienced and novice pigmentation artists frequently reach the hypodermis, owing to the difficulty in controlling the precise depth of pigment implantation. The skin's variable thickness and the limitations of human perception complicate this precision. Thus, the primary concern in practice should be managing pigment distribution across the skin layers rather than focusing solely on the elusive “sweet spot.”

11. Resistance of “thick” epidermis theory

When it comes to making a claim that “a longer needle is needed to penetrate thicker epidermis or that the resistance of the epidermis would actually depend on the epidermis thickness, those claims are also largely false.

There is no scientific proof that there was a linear correlation between the epidermis and dermis thickness, nor that a thicker epidermis would necessarily be harder to penetrate. The resistance skin layers offer to needle penetration is more complex than a simple function of their thickness. Other factors, like the density and composition of these layers, play a crucial role. The epidermis resistance depends first and foremost on the thickness and density of its upper layer - Stratum corneum.

A photo of the actual skin epidermis is on the left, and a cheerful woman is showing a peace sign on the right.

A photo of the actual skin epidermis is on the left, and a cheerful woman is showing a peace sign on the right.

Stratum Corneum: The Primary Barrier

The outermost layer of the epidermis, the stratum corneum, presents the main barrier to mechanical penetration, like needle piercing. This resistance is primarily due to the high concentration of keratin in the keratinocytes, making it particularly resistant to physical intrusions.

Contrast with the Papillary Dermis

Beneath the epidermis lies the papillary dermis, composed of a looser connective tissue matrix that includes collagen and elastin fibers. Due to its less dense and more pliable nature, the papillary dermis offers less resistance to needle penetration compared to the stratum corneum.

Factors Affecting Stratum Corneum Resistance

Age and Hormonal Changes. Can alter the skin's turnover rate and texture, impacting the properties of the stratum corneum.
Genetics. Influence skin characteristics, including stratum corneum thickness.
Environmental Exposure. Sun exposure can lead to thickening of the stratum corneum; harsh weather conditions can also alter its thickness.
Hydration Levels. Affect the skin's elasticity and pliability.
Skin Care Practices. Influence the skin cells' turnover rate and the stratum corneum's thickness.
Health and Nutrition. Impact overall skin health and characteristics of the stratum corneum.
Occupational Factors. Repeated mechanical friction can lead to thickening.

Skin Conditions Affecting Resistance

Calluses, Corns, Psoriasis, Eczema, Ichthyosis, Actinic Keratosis, Lichen Planus, Chronic Sun Exposure, and Diabetes: Each can contribute to stratum corneum thickness and density variability, influencing ease of needle penetration.

The resistance of the stratum corneum is thus a complex interplay of various biological, environmental, and lifestyle factors. This complexity goes beyond the simple measure of dermal thickness, underscoring the importance of a nuanced understanding of skin resistance in pigmentation procedures.

12. Potential Explanation for Misleading Graphics

Our analysis suggests a potential explanation for the inaccurate representation of skin layers in some pigmentation training materials: the confusion between "Thick" and "Thin" skin.

Thick Skin vs Thin Skin: A Comparison

Skin Structure: Skin, the largest organ of the body, comprises three main layers - the epidermis, dermis, and hypodermis. The primary difference between thick and thin skin lies in the epidermis and dermis thickness.

Characteristics of Thin Skin

Location. Covers most of the body, excluding the soles and palms.
Epidermis Thickness: Ranges from 0.07–0.15 mm.
Structure. Features hair follicles, sweat glands, and sebaceous glands.
Layers. Comprises four layers in the epidermis.
Function. Provides protection, sensation, and thermoregulation.

Characteristics of Thick Skin

Location. Found on the soles of the feet and palms of the hands.
Epidermis Thickness. This can be up to 1.5 mm, including the stratum lucidum layer.
Structure. Lacks hair follicles, sebaceous glands, and arrector pili muscles.
Layers. Contains an additional fifth layer, the stratum lucidum.
Function. Offers enhanced protection in high-friction areas.
Layer Analysis and Dermis Comparison
Stratum Basale to Stratum Corneum. Each layer has distinct characteristics, with the stratum corneum being the outermost layer in both skin types.
Dermis Variation. The dermis in thin skin is thicker and contains sweat glands and sebaceous glands, unlike in thick skin.

Conclusion on the Thick-Thin Skin Mix-Up Hypothesis

This analysis leads to the plausible hypothesis that the misrepresentation of epidermis thickness in training materials could be due to a mix-up between thick and thin skin images. The epidermis in thick skin, found on palms and soles, is significantly thicker because of the stratum lucidum layer, whereas the dermis is thinner. This contrast can result in misconceptions about the actual thickness of facial skin layers, which are crucial for precision in semi-permanent pigmentation procedures.

To avoid such misinterpretations, it is imperative for pigmentation training materials to accurately depict thin skin, especially when discussing facial pigmentation techniques.

13. Conclusions

Significant Discrepancies in Graphics

The graphics used in many pigmentation training materials are largely misleading due to significant errors in depicting the proportions between epidermis thickness and needle diameter. On average, these materials portray the epidermis as being 30-50 times thicker than the typical needle used for penetrating the epidermis. This results in a visual representation where the needle's penetration hole appears 50 times smaller than the depicted thickness of the epidermis.

Reality vs. Representation

In reality, the diameter of a typical needle is about five times larger than the thickness of the epidermis. This means that the graphics are off by a factor of 250 times, leading new artists to falsely believe that there is ample room within the epidermis for needle penetration. Such misconceptions can lead to the needle penetrating too deeply into the hypodermis, causing pigment migration and the problem known as "blowout."

Three Common Misconceptions Debunked

Implantation into the Basal Membrane. It's biologically and dermatologically implausible to implant pigment particles into the basal membrane. The thickness of this membrane is much thinner than typical pigment particles, making such implantation impossible.
Hitting the “Sweet Spot”. Theories suggesting the possibility of consistently targeting the uppermost part of the papillary dermis exceed our sensory capabilities. In reality, pigment often spreads into all dermis layers and sometimes into the hypodermis.
Adjusting Needle Length for “Thicker Dermis”. The idea that a thicker dermis requires longer needles or that a thicker dermis offers more resistance lacks scientific backing. The resistance of the epidermis is largely determined by the density of the Stratum Corneum, influenced by factors ranging from lifestyle to genetics rather than primarily by dermis thickness.

Potential Cause of Inaccurate Graphics

A possible explanation for these inaccurate graphics is the use of images depicting “Thick” skin, which has an epidermis over ten times thicker and a disproportionately thinner dermis. If trainers use such images as the basis for cross-sections of facial skin, further inaccuracies arise. However, this "Thick" skin is not present in facial areas, leading to substantial errors in training materials.

Exposing the 200-300 Times Proportional Inaccuracy in PMU Training Graphics

1. Research and Expert Reviews

2. The Structure of the Argument

3. Mistakes in Training Materials