Microneedling — also known as collagen induction therapy or percutaneous collagen induction (PCI) — is an advanced aesthetic technique that consists of the controlled creation of microchannels in the epidermis and superficial dermis using very fine-gauge needles. These microchannels stimulate the skin's natural healing mechanisms, triggering the production of collagen, elastin and endogenous hyaluronic acid.
In professional aesthetics, microneedling is used in combination with cosmetic active ingredients that penetrate through these microchannels, enormously enhancing treatment efficacy. This combination is the basis for using actives such as those from Institute BCN (Mesoceuticals) in dermapen protocols.
Mechanism of action of microneedling
When needles perforate the skin, a cascade of biological responses is triggered in three well-established phases:
Phase 1: Inflammation (0–3 days)
The controlled injury triggers the release of platelets containing growth factors such as PDGF (platelet-derived growth factor), TGF-α and TGF-β. The initial inflammatory response activates neutrophil and macrophage migration, releasing additional growth factors (FGF, EGF, VEGF). This process is essential for initiating tissue regeneration.
Phase 2: Proliferation (3–14 days)
Fibroblasts are activated and proliferate in response to growth factors. Synthesis of type III collagen (provisional, healing collagen) and new elastic fibres begins. Keratinocytes migrate to restore epithelial continuity. Neoangiogenesis also occurs during this phase.
Phase 3: Remodelling (14 days–2 years)
Provisional type III collagen is gradually replaced by type I collagen, which is more stable and organised. This phase can last up to 2 years and is responsible for the progressive, lasting improvement observed after a microneedling protocol. Elastin synthesis also continues during this period.
Differences between microneedling and other skin induction techniques
Microneedling vs. dermabrasion
Mechanical dermabrasion removes tissue layers by abrasion, generating a broad, non-specific superficial wound. Microneedling, in contrast, creates precise microchannels that allow most of the skin surface to remain intact, reducing recovery time and systemic inflammatory response. The epidermis is maintained as a protective barrier on 80–90% of the treated surface.
Microneedling vs. fractional lasers
Fractional ablative lasers (CO₂, Er:YAG) and non-ablative ones (Nd:YAG, 1550 nm) induce neocollagenesis via thermal means. Heat destroys tissue precisely but also generates protein denaturation in the transition zone. Microneedling acts mechanically, without heat, making it safer for dark phototypes (III–VI Fitzpatrick) where lasers carry a higher risk of post-inflammatory hyperpigmentation.
Microneedling vs. radiofrequency
Fractional radiofrequency (RF) acts on the deep dermis and subcutaneous tissue via electromagnetic energy. Microneedling acts primarily on the epidermis and papillary and superficial reticular dermis. Radiofrequency microneedling (RF-needling) devices combine both technologies.
Working depths by indication
Needle penetration depth determines the type of biological response and therapeutic indication:
| Depth | Tissue reached | Main indication |
|---|---|---|
| 0.25–0.5 mm | Epidermis | Active penetration, radiance, superficial texture |
| 0.5–1.0 mm | Dermo-epidermal junction | Blemishes, enlarged pores, fine wrinkles |
| 1.0–1.5 mm | Papillary dermis | Moderate wrinkles, superficial scars, mild sagging |
| 1.5–2.0 mm | Reticular dermis | Acne scars, recent stretch marks, moderate sagging |
| 2.0–2.5 mm | Deep dermis | Old stretch marks, hypertrophic scars (with caution) |
Advantages of microneedling over other rejuvenation techniques
- Safe for all phototypes: As it generates no heat, the risk of post-inflammatory hyperpigmentation is much lower than with ablative lasers.
- Reduced recovery time: Erythema and mild oedema generally resolve within 24–72 hours.
- Enhances active penetration: The microchannels created allow high molecular weight ingredients, such as high-weight hyaluronic acid or peptides, to penetrate dermal layers they would not normally reach.
- Progressive, lasting results: Neocollagenesis continues for months after treatment.
- Versatility of indications: From active acne (with caution) to ageing, blemishes, stretch marks and alopecia.
- Accessible cost: Compared to fractional lasers, microneedling represents a significantly lower investment for the aesthetic centre.
Device selection: dermapen vs. dermaroller
In professional practice, there are two main types of microneedling devices: dermarollers (needle rollers) and dermapens (motorised vertical tapping devices). Each has specific characteristics that practitioners must know to choose the most suitable for each indication and zone.
The dermapen allows easy depth adjustment during the session, which is especially useful for areas with irregular contours such as the eye area, nose or scars. The dermaroller applies more uniform pressure and is useful for large, flat surfaces.
For microneedling protocols with Institute BCN actives, both devices are compatible provided the indicated depths for each active ingredient and treatment zone are respected.
Ideal candidates for microneedling
Microneedling is indicated for adult clients presenting:
- Signs of chronological or actinic ageing (wrinkles, loss of firmness)
- Hyperpigmentation (melasma, sunspots, ephelides)
- Acne scars (atrophic, ice pick, rolling, boxcar)
- Stretch marks (especially recent, erythematous)
- Skin with irregular texture, enlarged pores
- Deep skin dehydration
- Androgenetic or diffuse alopecia (scalp treatment)
Absolute and relative contraindications
The practitioner must conduct a complete medical history before treatment to identify contraindications:
Absolute contraindications: active infection in the area (herpes, impetigo), severe active inflammatory acne, previous keloids or hypertrophic scars in the area, active psoriasis, isotretinoin treatment in the previous 6 months, uncontrolled coagulopathies, pacemaker or metal implants in the area, pregnancy.
Relative contraindications: very sensitive or atopic skin, active rosacea, recent use of topical retinoids, recent aesthetic procedures in the area.