For decades conventional wisdom in skin rejuvenation has postulated that an inflammatory response to accomplish collagen induction is essential. It was believed that inflammation was needed to attract cells to the site of injury, such as neutrophils and macrophages, which, in turn, release growth factors and cytokines responsible for repair. Clearly, the wound healing cascade does cause repair that may appear to be positive from a cosmetic perspective. However, given the overwhelming evidence in all other systems in the body that inflammation is to be avoided at all costs, why would this not hold true for skin as well? Inflammation is linked to arthritis, heart disease, strokes and cancer, and forms the very basis for aging.
The scientific evidence to support a paradigm shift includes the following:
Inflammation is absent in the embryo wound healing model for skin. Therefore, we can reasonably conclude that inflammation is not a necessary process or requirement for repair or “rejuvenation”.
Scarring is absent in embryo wound healing. All evidence in research points to scarring and destruction of normal tissue being the result of the inflammatory response.
Classic examples of a prolonged inflammatory response include severe burns and chronic leg ulcers. Scarring in these individuals is exaggerated, which begs the question of why we would want to provoke and prolong the inflammatory response in skin rejuvenation? Mimicking this model of wound healing does not make sense given the outcome. Yes, these are extreme cases demonstrating obvious outward signs of the process. Just because we cannot see outward evidence of a negative outcome does not mean that it is not present. In addition, negative outcomes may take decades to evolve, e.g. skin cancer after UVR. The long-term effects of light-based heat therapies are still unknown.
Fibroblasts can produce scar tissue or normal collagen, depending on the signals they receive that dictate their response or function. Inflammatory growth factors and cytokines induce scar tissue. Yes, one will get a result that can be viewed as cosmetic improvement. Given the fact that one can also get a result where normal collagen is produced by stimulating non-fibrotic or non-inflammatory growth factors and cytokines with less aggressive microneedling, why would we settle for anything less?
In our quest to produce collagen, it makes sense that we would avoid anything that breaks it down. The role of collagenase is well documented in this process. It is produced after any injury with two main peaks, the first within 1-7 days depending on degree of injury (to remove any non-viable tissue after injury), and the second at around day 14 (to re-organize the wound collagen). With this knowledge, inducing this enzyme repeatedly by provoking the inflammatory response any more frequently than the natural 28-day healing cycle will result in a permanent state of peaked collagenase which will be counter-productive to our goal.
In summary, provoking and prolonging the inflammatory response, while achieving a short-term cosmetic result, ignores the long-term consequences, and may well be deemed below best standard of care, or even “negligence”, in the near future.[wp_ad_camp_3]