Microneedling
Microneedling is a relatively new minimally invasive procedure involving superficial and controlled puncturing of the skin by rolling with miniature fine needles. Microneedling was initially introduced for skin rejuvenation, but now it’s used for a wide range of indications, including acne scars, acne, post-traumatic/burn scar, alopecia, skin rejuvenation, drug delivery, hyperhidrosis, stretch marks, and many more. It is very safe for dark skin types, where risk of postinflammatory pigmentation is very high with other techniques that damage the epidermis. Traditionally, it’s used as a collagen induction therapy for facial scars and skin rejuvenation, but it is now widely used as a transdermal delivery system for therapeutic drugs and vaccines.
The standard medical dermaroller has a 12 cm long handle with a 2 x 2 cm wide drum-shaped cylinder at one end studded with 8 rows and 24 circular arrays of 192 fine microneedles, usually 0.5–3mm in length and 0.1–0.25 mm in diameter. The microneedles are synthesized by reactive ion etching techniques on silicon or medical-grade stainless steel and pre-sterilized by gamma irradiation. Rolling with the standard dermaroller over an area of skin for 15 times results in about 250 holes per square cm up to the papillary dermis depending on the pressure applied. Each pass produces 16 micro punctures in the stratum corneum per square cm without damaging the epidermis significantly.
Micro punctures are created using microneedles to produce a controlled skin injury without actually damaging the epidermis. The micro injuries lead to minimal superficial bleeding and set up a wound healing cascade with release of various growth factors such as platelet derived growth factor (PGF), transforming growth factor alpha and beta (TGF-𝛂 and TGF-𝜷 ), connective tissue activating protein, connective tissue growth factor, and fibroblast growth factor (FGF). The needles also break down the old hardened scar strands and allow it to revascularize. Neovascularization and neocollagenesis is initiated by the migration and proliferation of fibroblasts and laying down of intercellular matrix. Another proposed hypothesis explains that resting electrical membrane potential of cells is approximately -70 mV, and when needles come near the membrane, it increases quickly to -100mV, triggering increased cell activity and the release of various proteins, potassium, and growth factors from the cells into the exterior leading to the migration of fibroblasts to the site of injury, which causes collagen induction. The needles do not create a wound in a real sense, just fooling the cells in believing that the injury has occured.
Consumers can buy at-home microneedling rollers over the counter. But for best results, microneedling should be administered by a dermatologist using more advanced equipment. The dermatologist can adjust the device depth according to the area of the skin and deposit medication, such as topical tretinoin or vitamin C, deeper into the skin. At-home microneedling devices only superficially affect the skin, penetrating just the outer layer, the stratum corneum or epidermis and reaching 0.25 mm deep. Professional devices can go deeper (2 mm to 3 mm deep), reaching the dermis. Professional devices are also electrically powered and evenly pushes the microneedles into the skin. Home versions rely on manually rolling the barrel over the skin to create small punctures.
References:
Singh, A., & Yadav, S. (2016). Microneedling: Advances and Widening Horizons. Indian dermatology online journal. Retrieved March 21, 2022, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4976400/
Yale Medicine. (2021, June 23). Microneedling. Yale Medicine. Retrieved March 21, 2022, from https://www.yalemedicine.org/conditions/microneedling
MICRONEEDLING
Microneedling is a popular cosmetic procedure used to help tone, tighten, and smooth the skin. This can reduce scars, wrinkles, and acne. Microneedling is named after the micron size of its needle, they vary from 10–2000 μm in height and 10–50 μm width. The depth of the needle varies based on the different parts of the body being performed on. The most common location microneedling is done is on the face. However, patients can receive treatment on their back, thighs, neck, and legs to reduce aging marks and stretch marks. The needle penetrates through the epidermis tissue, creating tiny holes in the upper skin layer. Multiple treatments are suggested for better and longer results. These needles can be found on rollers, stampers, and pens. Microneedling has no effect on skin tones and different photo types, unlike laser, therefore it is preferred for patients with darker tones. In addition, microneedling is less expensive than lasers. The procedure lasts around half an hour and is usually performed by dermatologists, plastic surgeons, and/or cosmetic surgeons. When inserting the needle, collagen, and elastin production in the skin increases. This is the cause of improved skin elasticity, firmer skin, and reduction of wrinkles and fine lines. Other benefits include reduced hyperpigmentation, enlarged pores, stretch marks and increased hair growth in patients with alopecia. Radio-frequency micro-needling can also benefit hyperhidrosis by puncturing the skin and sending radio-frequency waves to the sweat glands to reduce sweating. One of the earliest used and known microneedling tools was the Dermaroller. When the derma roller was used on acne scars, there was proof of reduced scarring. When used in addition to minoxidil, as a form of drug delivery, increased hair growth was shown in patients.
Different types of microneedles are solid microneedles, coated microneedles, dissolving microneedles, and hollow microneedles. Microneedling can be combined with radio frequency to help pass the epidermal surface. Treatments usually have minimal side effects with some patients experiencing redness, irritation, and bleeding for a few days. Treating with topical anesthesia can help with irritation. After the procedure, patients experienced pain, discomfort, erythema, and swelling. Patients allergic to nickel may experience allergic reactions from the needle. Signs of this include burning, hives, itching, and redness. In an effort to remain sanitized and safer, disposable needles can be used. This can decrease the spread of bacteria and the risk of infection. Patients with active skin conditions such as active acne, skin infections, moles, eczema, and psoriasis should not receive micro-needling. Patients taking anticoagulant medications should avoid microneedling due to the increased bleeding risk.
In conclusion, microneedling has been proven effective and safe for many people. it is noninvasive and inexpensive compared to other procedures. The best way to see if microneedling is safe for you is to consult with a board-certified dermatologist. To increase collagen production and skin elasticity, it is recommended to take Vitamin A and C in addition to micro-needling sessions. Wearing sunscreen and stopping the use of retinoids also increase the effects of micro needling.
Dana Alessa, Jason D. Bloom, Microneedling Options for Skin Rejuvenation, Including Non–temperature-controlled Fractional Microneedle Radiofrequency Treatments,
Facial Plastic Surgery Clinics of North America,28;1:1-7. ISSN 1064-7406,ISBN 9780323695961,
Juhasz MLW, Cohen JL. Microneedling for the Treatment of Scars: An Update for Clinicians. Clin Cosmet Investig Dermatol. 2020 Dec 22;13:997-1003. doi: 10.2147/CCID.S267192. PMID: 33376377; PMCID: PMC7764156.