The pursuit of physical perfection has been ingrained in human nature since the dawn of civilization. Throughout history, people have sought various methods to enhance their bodies and add volume to areas that lacked it. Unfortunately, many of these experiments were detrimental to health and failed to achieve the desired results. However, in the latter half of the twentieth century, the concept of safe and effective volume augmentation finally materialized in the form of fillers.
Collagen: Safety Testing The study of bovine collagen and its interaction with the human body spanned two decades, culminating in FDA approval for the use of collagen-based products in restoring soft tissue volume. For a considerable period, collagen fillers reigned as the most popular choice. They encompassed dermal filler injections as well as collagen fillers derived from xenogenic (bovine, porcine), homologous (human), and autologous (own) collagen.
Xenogeneic implants pose a greater risk, as they carry the potential for allergic reactions, necessitating sensitivity tests. Collagen itself is fully biodegradable, which is a positive attribute from a safety standpoint. However, its biodegradable nature requires frequent reinjections. To address this issue, collagen began to be combined with other substances, such as polymethyl methacrylate granules. Consequently, collagen-based fillers exhibited varying periods of biodegradation (ranging from one year to infinity), but their safety profiles also changed, as they introduced the potential risks associated with non-degradable fillers in addition to the risk of allergies. While the development of an autologous fibroblast culture with collagen and elastin fibers from a patient’s own skin showed promise, this labor-intensive method remained in the clinical trial stage. Instead, new fillers emerged that prioritized high-quality production, ease of use, and effective correction within a suitable timeframe.
An Exception Semi-permanent fillers, such as L-polylactic acid and calcium hydroxyapatite, have garnered significant interest but are often accompanied by concerns. This category stands out due to its stimulatory effect, leading to noticeable fibrosis in the injected area. This property proves useful when lifting sagging skin and achieving long-term volume restoration. One of the primary applications for this group of fillers, particularly L-polylactic acid, is facial lipoatrophy in HIV-infected patients. These individuals often experience severe soft tissue deficiency without a robust immune response to conventional treatments. While these fillers have a substantial history, their reputation includes both positive outcomes and negative reviews.
Analysis of adverse experiences often reveals frequent violations of injection techniques and patient selection criteria. Working with these fillers can be challenging due to their mode of action. While they provide a volumizing effect, their significant impact lies in stimulating the dermis and hypodermis, resulting in fibrosis formation. Dilution is a common practice with these fillers. In recent years, there has been a trend toward using less concentrated solutions. Although a more liquid solution may have a less pronounced effect, it stimulates fibrosis without the risk of overcorrection.
Soft Tissues: Reinforcement Without Waiting for Suspension Hyaluronan, the sodium salt form of hyaluronic acid (HA), has a long history predating the advent of fillers. Nearly a century ago, researchers successfully isolated this substance from biological materials, and its applications rapidly expanded in the medical field. In aesthetic medicine, HA initially appeared in the form of external agents, such as serums, masks, and creams. HA’s use in cosmetics is attributed to its exceptional hygroscopicity, allowing it to retain significant amounts of water, which in turn moisturizes the skin.
In the 1980s, the first HA-based injectable fillers appeared. Since then, a wide range of HA-based injectable fillers has been developed, some of which are very similar to each other, while others differ significantly from each other. Preparations such as lipoinjekt have proven very well in the process of use. Naturally, the main quality factor lies in the search for reliable raw materials for hyaluronic acid. Given the amount of HA used in various fields of medicine, bacterial synthesis is the main source for the production of hyaluronic acid. Most of them are synthesized by non-pathogenic strains of Streptococcus, although HA produced by Bacillus subtilis is also available. HA can have a different molecular weight, which leads to different effects, sometimes even opposite.
Painless and Safe Modern fillers often consist of stabilized hyaluronic acid and may contain additional ingredients that influence the properties of the product. One frequently encountered additive is lidocaine, a well-known anesthesia drug. While the presence of lidocaine does not affect the injection procedure itself, the technique for injecting these fillers typically deviates from the traditional retrograde approach. Instead, a combination method is recommended: a small amount of filler with an anesthetic is injected antegrade initially, followed by the retrograde injection of the remaining volume. This technique enhances the procedure’s tolerability. However, it’s crucial to note that lidocaine can cause tissue edema, making immediate post-procedure assessment challenging. Combining fillers with anesthetics is currently a popular topic, with some specialists manually mixing the filler with lidocaine using connectors.
Fillers of the Future Drawing parallels with meso cocktails, which are prepared on the spot, one may wonder how evenly the additional components in fillers are distributed. Could it be possible that, at different stages of the procedure, a filler with an additive enters the tissue while an additive with a filler is injected at other times? This phenomenon is evident when creating a cocktail with hyaluronic acid: the initial stages involve a more liquid form of the drug, while the later stages consist of a more viscous version. Aestheticians must consider this nuance when selecting a specific protocol, determining the sequence of techniques, and reinserting the needle into the same zones.
This aspect has recently gained significant importance. While therapeutic drugs have resolved this issue by using HA-based compositions with attached components, fillers are entering a new phase in their history. Traditional HA fillers might soon be replaced by new combinations that integrate volumizing effects with uniform and long-lasting therapeutic benefits. These combinations may include antioxidants, making them ideal for photoaging skin, stimulating factors like polylactic acid for long-term soft tissue volume restoration, or peptides for pronounced therapeutic effects alongside filling properties.
Science continues to progress at an astounding rate. The past century witnessed remarkable advancements in technology, chemistry, and biology, providing us with invaluable knowledge and significant achievements. Nevertheless, these accomplishments merely scratch the surface of what lies ahead in our ongoing exploration and understanding of cosmetology. Although cosmetology has emerged as a distinct field in recent years, it is evident that it is rapidly evolving in terms of fundamental principles, future prospects, and innovative projects.
