### Date : 2025-04-13 16:58 ---- # **3.2 Pigment Formulations in Scalp Micropigmentation (SMP)** The **pigment formulation** used in SMP is one of the most critical factors determining the **natural appearance, long-term stability, and safety** of the procedure. SMP pigments must be specifically designed for **scalp application**, which differs significantly from traditional tattoo and permanent makeup inks in terms of **particle size, composition, concentration, and behavior over time**. --- ## **3.2.1 Characteristics of Ideal SMP Pigment** An ideal SMP pigment must meet the following criteria: |**Property**|**Description**| |---|---| |**Color Stability**|Should fade gradually over time without turning blue, green, or red| |**Particle Size**|Micronized for consistent, even diffusion in the dermis (typically 6–8 microns)| |**Viscosity**|Balanced to avoid migration and ensure proper absorption| |**Biocompatibility**|Non-toxic, hypoallergenic, inert in the skin| |**UV Resistance**|Resistant to ultraviolet-induced breakdown or oxidation| |**Sterility**|Pre-sterilized and free from microbial contaminants| --- ## **3.2.2 SMP Pigment vs. Tattoo Ink vs. Permanent Makeup Pigment** |**Aspect**|**SMP Pigment**|**Tattoo Ink**|**Permanent Makeup Ink**| |---|---|---|---| |**Purpose**|Mimic hair follicles|Artistic body art|Eyebrows, lips, eyeliner| |**Pigment Type**|Carbon-based or iron oxide|Heavy metal-based (multi-color)|Iron oxide-based| |**Color Behavior**|Fades to lighter version of original shade|Often turns blue/green/red over time|Can shift to orange/pink tones| |**Depth of Placement**|0.5–1.5 mm (epidermal-dermal junction)|1.5–3 mm (deep dermis)|1–2 mm| |**Longevity**|3–5 years before touch-up|Permanent (fading varies)|Semi-permanent (1–3 years)| |**Migration Risk**|Low (with correct technique)|Moderate (deep and saturated)|High (especially around thin skin)| **Conclusion**: Only **SMP-specific pigments** should be used for scalp applications. Traditional tattoo ink leads to **color distortion** and **undesirable long-term results**. --- ## **3.2.3 Types of Pigments Used in SMP** ### **A. Carbon-Based Pigments (Most Common)** - Made from **refined carbon black suspended in water or glycerin**. - Known for producing **crisp, clean, natural-looking follicle dots**. - Fade **gradually to lighter gray** tones, avoiding unnatural colors. - **Highly responsive to laser correction** (if removal is necessary). **Pros:** - Natural appearance, especially for **Fitzpatrick III–V skin types**. - **Stable, predictable fading pattern**. - Compatible with all hair colors (black, dark brown, even shaved gray). **Cons:** - **Requires precise dilution**; too dense may appear **too dark initially**. - Needs **multi-session layering** to control final shade. **Common Brands:** - **Folicule** - **Good Look Ink** - **Scalp Aesthetics** - **5PM Shadow** --- ### **B. Iron Oxide-Based Pigments (Less Common in Modern SMP)** - Historically used in **cosmetic tattooing** and some early SMP systems. - Less color stable, more prone to **oxidation** (e.g., turning reddish or orange). - **Heavier particles**—may not be absorbed evenly. **Pros:** - Lower initial visibility (used for test spots). - Useful in **corrective camouflage** (e.g., blending scars). **Cons:** - Greater risk of **color change** over time. - **Harder to remove** with laser treatment. - **Not recommended for modern SMP procedures**. --- ## **3.2.4 Pigment Color Selection Based on Skin Type and Hair Tone** ### **A. Pigment Selection by Fitzpatrick Skin Type** |**Fitzpatrick Type**|**Recommended Pigment Shade**|**Notes**| |---|---|---| |**I–II (Fair Skin)**|Light to medium gray-black|Avoid overly dark pigments to prevent harsh contrast| |**III (Beige–Olive Skin)**|Medium gray-black|Natural blend for most Koreans| |**IV–V (Tan to Brown Skin)**|Medium to dark charcoal|Warmer undertones required to match melanin| |**VI (Dark Brown to Black Skin)**|Dark charcoal to black|Use with caution—ensure pigment doesn't over-saturate| ### **B. Adjusting Pigment for Hair Color** - **Black or dark brown hair** → Carbon black (standard SMP pigment). - **Gray or salt-and-pepper hair** → Diluted carbon black to match undertone. - **Red or light brown hair** → Usually not shaved bald; SMP only used for density enhancement, not full follicle simulation. --- ## **3.2.5 Pigment Dilution Techniques** Dilution allows the practitioner to **control the darkness and density** of the final result. |**Dilution Ratio**|**Result**|**Use Case**| |---|---|---| |**1:0 (Undiluted)**|Deep, dark tone|Scar camouflage, dark scalp tones| |**1:1**|Standard SMP application|Normal-density SMP, most skin tones| |**1:2 to 1:4**|Light tones|First passes, lighter skin types, soft hairline blending| |**1:5+**|Test dots or subtle shading|For light skin patients or frontal feathering| **Diluent Examples:** - **Sterile water** - **Glycerin-based diluent** - **Specialty SMP diluters** (preserve viscosity and sterilization) --- ## **3.2.6 Pigment Behavior Over Time** ### **Fading Timeline** - **Day 0–7**: Pigment appears darker due to inflammation and scabbing. - **Week 2–3**: Scabs fall off; pigment looks 30–40% lighter. - **Week 4–6**: Pigment stabilizes; actual retention can be judged. - **Year 1–3**: Gradual fading depending on sun exposure, skin turnover, and immune activity. - **Year 3–5**: Touch-up often required for density and definition. ### **Common Causes of Pigment Fading** - **UV exposure** - **Excessive sweating** (especially in oily scalps) - **Immune response** clearing pigment via macrophages - **Inadequate post-care** - **Incorrect depth or pigment saturation** --- ## **3.2.7 Safety and Regulatory Considerations** ### **Sterility and Composition** - Only use **pre-sterilized, lot-numbered, and individually sealed pigments**. - Avoid pigments with **heavy metals (e.g., mercury, cadmium, chromium)**—may cause allergic reactions or **incompatibility with MRI**. ### **Hypoallergenicity** - Conduct **patch testing** for patients with history of allergies or sensitive skin. - Use **EU and FDA-approved pigment lines** when available. ### **Laser Compatibility** - Carbon-based pigments respond well to **Q-switched Nd:YAG laser removal**. - Iron oxide-based pigments may **oxidize to dark tones** when exposed to lasers—caution required. --- ## **3.2.8 Conclusion** SMP pigments are **fundamentally different from tattoo and cosmetic pigments**, requiring careful **selection, dilution, and application** based on **skin type, hair color, and treatment goals**. ✔ **Carbon-based pigments are preferred** for their **color stability and natural fading**. ✔ **Proper dilution and technique** ensure **natural blending and sharp follicle simulation**. ✔ **Long-term results** depend on **pigment quality, depth control, and aftercare**.