What is a dermal filler?
Dermal fillers are gel-based implants that are injected into the skin to correct various aesthetic imperfections. These medical devices are also referred to as aesthetic implants, soft tissue fillers, cosmetic injectables, and wrinkle fillers. Due to tremendous scientific advancement in the medical and aesthetic industries, dermal fillers are now produced with varying degrees of ingredients and concentrations to address numerous skin defects.
What are the indications for dermal filler injections?
The most popular indication for soft tissue filler injections is the correction of facial wrinkles and creases. These fillers help to strengthen the weakened skin structure for a more plump and smoother appearance. Besides that, many brands of dermal implants are now incorporating skincare ingredients such as vitamins, minerals, amino acids, and plant extracts to correct premature ageing signs such as dehydration, dullness, scars, hyperpigmentation, and superficial wrinkles. These medical devices are usually known as mesotherapy or biorejuvenating solutions, depending on the concentration of the active ingredients present. The skin-rejuvenating solution containing a cocktail of vitamins and other anti-aging ingredients enhances the repair and genesis of dermal cells, resulting in a rejuvenated appearance of the skin. As well, patients experiencing facial volume loss can also benefit from dermal fillers. In addition to treating early signs of ageing, aesthetic implants can also be used as effective non-surgical alternatives to augmenting facial features like the lips, nose, and facial contours. These fillers are usually very viscoelastic and malleable to easily shape the facial features.
Different types of dermal fillers
The various indications explained above are only possible due to the different types of dermal fillers available on the market. As of now, there are a total of 5 types of implants that can be used to treat aesthetic defects.
- Collagen-based fillers: Collagen is a versatile protein that is found abundantly in the human body, providing mechanical strength to various bodily structures such as the skin and bones. Synthetic collagen is extracted from bovine or even human cells that are highly purified to be free from any proteins. Following the implantation of a collagen-based injectable gel, collagen is replenished in the skin. Facial lines and creases are then seamlessly erased. These soft tissue fillers are biodegradable and only improve the skin temporarily for about 3 to 4 months. The short residence time make these fillers 1 of the shortest acting filler materials.
- Hyaluronic acid-based fillers: Arguably the most renowned type of injectable filler, hyaluronic acid is actually a type of complex carbohydrate produced naturally in the body. Due to its immense water-binding capacity—1 gram of hyaluronic acid can hold up to 6 litres of water—hyaluronic acid cells function as a potent humectant that delivers moisture and nutrients for the optimal performance of other cells. The gradual decrease in quality and quantity of hyaluronic acid as a result of ageing gives rise to the formation of skin wrinkles and lines. The hyaluronic acid molecules used in the injectable gel are sourced biotechnologically from the cell structures of gram-positive bacteria. However, some companies manufacture hyaluronic acid-based gel from animal sources such as bovine and rooster. Nevertheless, the viscoelasticity and concentration of these fillers can be altered using various reticulating technologies. Although hyaluronic acid-based fillers tend to last longer (about 6 to 12 months or more) than collagen fillers, they will still be metabolised into the surrounding tissues. Some examples of hyaluronic acid fillers are Belotero Balance and Juvederm Ultra XC.
- Calcium hydroxylapatite-based fillers: Just like collagen and hyaluronic acid, calcium hydroxylapatite (CaHA) is also found naturally in the human body. Implants made of this material typically consist of uniform CaHA micro-particles suspended in a smooth and aqueous carrier gel. Calcium hydroxylapatite fillers are unique due to their biostimulating activity. Once injected into the problematic skin, the carrier gel will instantly plump the collapsed skin structure while the CaHA microspheres promote the growth of new collagen fibres. This fully biodegradable and semi-permanent filler will be broken down gradually within a year or more, leaving behind smooth and reinforced skin. Radiesse is a popular CaHA filler.
- Poly-L-lactic acid-based fillers: Poly-L-lactic acid is a non-toxic, semi-permanent, and synthetic polymer that is renowned for its biomaterial quality. It has a long-standing history of safe use in various medical applications such as bone plates, sutures, soft-tissue implants, and drug-delivery systems due to its durable and tissue-friendly properties. Fillers made from PLLA are regarded as biostimulators, because they revitalise collagen production instead of delivering instant aesthetic improvements. Over time, the injected areas will become smoother and plumper, and these desirable results will last for approximately 2 years. Sculptra is a popular PLLA filler.
- Polymethylmethacrylate-based fillers: Polymethylmethacrylate (PMMA) is a completely synthetic acrylic polymer, commonly known as Perspex or Plexiglas. This polymer found its initial use as a roofing material, as it can withstand extreme temperature variations. It is now a permanent fixture in aesthetic medicine. The fillers consist of PMMA microspheres that are suspended in a carrier gel. Once injected, the non-biodegradable implant remains under the skin permanently to correct any dermal wrinkles. Artefill is 1 such filler.
No matter the type of filler, the success rate of soft tissue filler injections depends largely on the physician’s expertise, amount of filler injected, and the patient’s age, skin condition, and lifestyle behaviours.