# Facial Anti-Aging Treatments with Soft Peeling and Microneedling Technique
## 1 Introduction  
The interest in maintaining a young and attractive appearance in an era with increasingly hectic rhythms has generated a pressing demand for effective aesthetic procedures associated with the shortest possible recovery period, stimulating the search for non-invasive, yet successful, solutions. Different endogenous stressors (e.g., endocrine-metabolic diseases) and/or exogenous stressors (e.g., ultraviolet radiation) can be the cause of skin functional alterations and/or structural problems that can damage skin integrity to varying degrees of severity [1]. Patients seeking treatment to rejuvenate photodamaged skin wantto reduce pigmentation irregularities, have a smooth texture, reduce wrinkles, and improve skin laxity. Many techniques have been proposed for the treatment and prevention of facial aging, such as laser resurfacing [1; 2], deep chemical peels [3], and dermat abrasion [4], which involves the destruction of the epidermis, with damage to the dermis, and consequently initiates an inflammatory response, resulting in the production of new collagen, vascular texture and skin regeneration. However, the use of these techniques is often associated with the production of thicker bundles of collagen, transient alteration of the ratio between type 1 and type 3 collagen, alteration of the morpho-structural conformation of the bundles of fibers [5; 6; 7; 8], and a greater susceptibility to photo damage with the possibility of post-inflammatory hyperpigmentation and post-procedural complications [9; 10]. Non-ablative alternatives that avoid these types of complications and reduce recovery time include peeling and microneedling (MN), and percutaneous collagen induction (PCI), a technique that uses a manual or motorized microneedle device. The motorized MN is equipped at the tip with disposable sterile cartridges containing micro needles in a variety of numbers, and this allows the depth and frequency of penetration to be adjusted depending on the indication and the area to be treated. By sliding the device over the skin, microperforations of the skin are created, triggering a controlled post-traumatic inflammatory response (with the simultaneous release of growth factors and the formation of collagen and elastin) [11; 12; 13]. In addition to the aforementioned intrinsic capabilities related to the penetration of the needle alone with consequent mechanical trauma, MN can also be used to convey substances and drugs applied to the skin surface. The transdermal administration of therapeutics is severely limited by the poor permeability of human skin; most molecules do not cross the skin at therapeutically relevant rates. Since the stratum comeum has a variable thickness of a few tens of micrometers, the microneedles have a length of a few hundred microns and are therefore able to cross the transcorneal barrier and provide transport routes to the underlying tissues [14; 15]. Peeling as an anti-aging technique is relatively recent and increasingly used. From the use of single acids, we have moved on to formulations composed of combinations of different acids, in specific concentrations to ensure greater effectiveness of the treatment at the proposed target (the so-called compound peelings, or combinations of multiple substances in the same device) [16]. Compound peels, in addition to their specificity, offer the advantage of a synergistic effect between the different substances [17]. Superficial peels, combined and not combined, have allowed a drastic reduction in the onset of adverse events typical of medium and deep peels, such as systemic toxicity (e.g., phenol), post-treatment hyperpigmentation, hypopigmentation, keloids, erythema, telangicastae, millet grains, infections, and herpetic reactivations [18]. Superficial peels have a limited effect on the epidermis as they do not involve systemic absorption or diffusion into the underlying tissues (dermis and hypodermic adipose tissue).