Medical microneedling is one of the most popular skin treatments among patients.1 Also known as collagen induction therapy or percutaneous collagen induction, it is a medical-grade cosmetic procedure that involves using micro needles to create controlled injuries in the skin, preserving the epidermal layer.1 These micro-injuries trigger cascades of reactions to the body’s natural wound healing response, and promotes the production of collagen and elastin whilst remodelling and smoothing the skin. It is also used for transdermal drug delivery.1,2
Mechanism of microneedling
Microneedling results in the wound healing in the dermis to be triggered, and multiple growth factors released.3 These include fibroblast growth factor, platelet-derived growth factor and transforming growth factors TGF-a and TGF-b, leading to the proliferation and migration of fibroblasts and laying down the intracellular matrix, causing neovascularisation and neocollagenesis.3 Tissue remodelling occurs over the subsequent 18 months.2 Fibronectin matrix and collagen type III forms, which is eventually replaced by type I collagen.4 This remodelling process results in skin tightening and scar reduction.
Needle lengths or depth of penetration can vary from 0.1mm-0.5mm for home devices and 0.5mm-3.5mm for devices to be used in medical settings.1 Adjustable depth allows practitioners to target specific concerns from epidermis to dermis and allow transepidermal or transdermal drug delivery.5
Many studies demonstrate that microneedling is effective for treating atrophic acne scars, hypertrophic scars, keloids, striae distensae, androgenic alopecia, melasma and acne vulgaris, as well as triggering overall skin rejuvenation.1,2,4,6,7 Microneedling showed successful results when used alone and when combined with mesotherapy and/or radiofrequency (RF).1,8,9 Compared with other treatments, a systematic review showed similar results but was preferred due to minimal side effects and shorter downtime.6
The evolution of microneedling
The concept of ‘injury – repair’ dates back thousands of years. Using needles on the skin for therapeutic purposes was described in the book of Ancient Chinese Medicine called The Yellow Emperor’s Classic of Internal Medicine, dating from 100BC.8 They used animal and bamboo bones attached to stones to stimulate skin where healing was needed.10 Nowadays, acupuncture is used to improve the body’s function and promote the natural self-healing process, which is exactly what microneedling does, although with different indications and outcomes.
The first report of controlled injury and microneedling procedures was in 1905 by German dermatologist Dr Ernst Kromayer.11 He used dental burs and scalpels powered by motor-driven flexible cord equipment (like a foot driven dental drill) to treat scars, birthmarks and hyperpigmentation.11 His experiments allowed him to conclude that preserving the reticular dermis promoted scarless healing.11
In 1960, Dr Norman Orentreich, a US dermatologist who pioneered the field of hair transplantation, noticed that small surgical subcisions to create micro punctures in the skin helped improve the appearance of scars and promote hair growth.12 However, the technique was invasive and focused on hair growth and specific areas only. Dr Orentreich continued the research, and in 1995, together with his dermatologist son Dr David Orentreich, published a report on surgical subcision for the correction of depressed scars and wrinkles.12
The modern version of microneedling, as we know it today, was first described in the 1990s.1 In 1997, plastic surgeon Dr Andre Camirand and chemical engineer Professor Jocelyn Doucet used empty tattoo guns without ink on scars.13 The study described needle dermabrasion using a ‘tattoo pistol’ which improved the appearance of scars.13
Soon after, a process called ‘dermarolling’ emerged.1 This technique involved rolling a cylinder covered in fine needles over the skin, creating micro-channels, without the need for surgery. Dermarollers were initially used to improve the absorption of topical medications, but it was soon discovered that they also enhance collagen and rejuvenate the skin.1
Following Dr Orentreich’s work, plastic surgeon Dr Desmond Fernandes noticed that treating upper lip lines with a 15 gauge needle, injected in different directions, showed an improvement in the appearance of lines, but caused significant bruising.14 Independently, German inventor Horst Liebl developed a handheld drum shaped rollerdevice with multiple fine needles, which he called a ‘Dermaroller’. He patented it in 2000 as a device for the delivery of active ingredients through the skin.1 Dr Fernandes invented his own similar device to treat not only scars, but various skin conditions, and found that it stimulated collagen production, improved skin texture and reduced scars and wrinkles.14
Since then, microneedling has gained popularity in the field of dermatology and aesthetics. The technique has evolved, and devices have become available in various sizes and needle lengths, from handheld rollers and stamps to automated pens and devices to stimulate the body’s natural healing response and collagen production.
In the early 2000s, the potential of microneedling was recognised as a standalone procedure for skin rejuvenation. The development of automated microneedling devices further improved the precision, control and safety of the treatment. These devices allowed for adjustable needle depth, therefore ensuring precise, consistent and controlled punctures of the skin.5-7
Microneedling gained significant popularity in the late 2000s and early 2010s as more clinical studies supported its efficacy and safety.1,2,4,6,7 The procedure’s ability to stimulate collagen production and improve skin texture, along with minimal downtime and side effects, contributed to its widespread adoption in both medical and aesthetic practices.
Current climate of microneedling
Today, microneedling is a widely recognised and commonly performed procedure for various skin concerns. It is often used in combination with treatments such as topical serums, platelet-rich plasma (PRP) and chemical peels to further enhance its effects.15-21 While its exact history spans several decades, the continuous advancements in technology and techniques have made it an increasingly popular and effective tool in the field of skin rejuvenation.
The roller device is widely used, whilst an electronic pen-shaped device that has adjustable settings to control speed and depth of needle penetration has also been popular. Treatments such as PRP and mesotherapy serums are also used to potentiate the remodelling and scarless healing of the skin, addressing various concerns simultaneously.6,15,20,21
Some modern microneedling devices deliver RF energy through fractional microneedling RF (FMRF). This causes controlled thermal injury directly to the dermis by generating a current between paired insulated microneedles.5,7,22 Previous studies have demonstrated the efficacy of RF microneedling for skin tightening, wrinkle and acne scarring reduction. These studies reported that the MFRF treatment resulted in significantly less post-inflammatory hyper- or hypopigmentation compared to fractional CO2 and Nd:Yag lasers.5,6,14,22 Furthermore, studies have also highlighted the efficacy of combining RF microneedling rather than using microneedling alone or RF alone.23,24
The first generation of FMRF used insulated needles for skin rejuvenation and acne scars. The insulated needles allowed energy flow only through the tip of the needle, resulting in small coagulation in the dermis.7 Disadvantages to these devices were significant pin-point bleeding during treatment and the need for several passes at different needle lengths to treat the entire dermis.25
The new generation of FMRF devices use electronic smooth motors to allow easily controlled gliding through the skin, minimising penetration trauma and patient discomfort. They also provide a choice of insulated and non-insulated needle cartridges and a variety of sizes to treat different skin types.7
New modern devices are very adaptable in terms of penetration depth and energy output, which allows clinicians to tailor their treatment protocols with precision.6 With the development of topical products for transdermal drug delivery, FMRF is becoming a popular and effective treatment with short downtime, with potential application to treat most skin conditions, types and colours in aesthetics.6,7
The future of microneedling
The broad application of microneedling leaves room for more research and combination approaches to be trialled. The skin is a very accessible tissue with great regenerative capacity; therefore, it serves as a potential organ for the development of antiageing, therapeutic and prophylactic genetic medicines.26
Chen et al. described a novel trend and research area exploring microneedling for cell therapy.27 The research showed promising results for tissue regeneration, cancer immunotherapy, skin immune monitoring and targeted cell delivery.27 This research provides future perspectives toward the development and application of microneedles for cell therapy and regenerative antiageing medicine.
Furthermore, Chabri et al. demonstrated that microneedling can be used for intradermal delivery of agents for localised treatment of genetic diseases such as epidermolysis bullosa.26 Microneedling may also be combined to dye poorly pigmented hairs and improve laser hair removal, as it has been shown that it dilates the follicular infundibulum and increases the transfollicular absorption of melanin.9
An evolving treatment
Although microneedling has historical roots, the modern techniques and devices used in the procedure have been developed in recent years to ensure safety and effectiveness. Microneedling technology has improved in needle design, device automation and the addition of new features such as RF energy. These advancements aim to enhance the effectiveness of microneedling and address specific skin concerns such as wrinkles, fine lines, scars, hyperpigmentation and stretch marks.
