Introduction and History
Injectable fillers date back as far as the end of the 19th century. At the beginning, mineral oils such as paraffin where used for both cosmetic and reconstructive purposes. There were of course obvious complications to the use of these materials: granulomas, necrosis, and infections among the others.
Other substances were later used like silicone, but were banned eventually due to being unsafe and causing too many adverse reactions in most countries of the world. In the USA and other countries silicone is still FDA approved, but only for retinal detachment; nevertheless their off-label use is still ongoing as well as the use in countries where it has not been banned.
Hyaluronic Acid (HA) was first discovered and studied in the 1930s. It is a substance present in all vertebrate species and some bacteria and nematodes too.
It has revolutionized the field of aesthetic medicine due to the great results provided, safety profile and minimum to no downtime after procedure for the patients. About 80% of the fillers injected worldwide is HA-based.
Mechanism of Action
Hyaluronic Acid (HA) is quickly metabolized by the human body within 24-48h to its metabolites water and carbon dioxide. To prevent this, proprietary engineering techniques (molecular cross-linking) have been developed to make it last longer.
HA binds water more than 1000 times its weight, thus creating volume where injected.
As explained in a previous article, not all wrinkles are the same. Hyaluronic Acid is very effective against wrinkles generated by loss of volume under the skin. It is effective and used for shaping and contouring purposes too.
The following are the most common applications: fine lines of the face, glabellar complex, perioral and periocular lines and folds, marionette lines, nasolabial folds, nose reshaping, chin augmentation, scars treatment (acne, traumatic, etc.), cheek and temporal fossa augmentation, brow elevation, lips augmentation and contouring, tear trough.
History of severe allergies, anaphylaxis and bleeding disorders, pre-existent infections at the selected injection site. Pre-treatment consultation and informed consent will make sure to avoid the risk of any inconvenience and set realistic expectations for the patients.
Duration of the Effects
Each individual is different and so it is the duration of HA fillers in the body. The area treated affects the duration too: the more motion there is (ie. Lips) the less it will last. Less motion (ie. Zygoma) longer effect. To give an idea anyway it is expected to last between 3-12 months depending on product used and treated area.
Complications, Risks and Adverse Effects
Although very rare, as any treatment there is the possibility of incurring in complications and adverse effects.
Pain, swelling, bruising, hypersensitivity reactions, granulomas, necrosis and inappropriate placement have been reported in literature. Some of these resolve without intervention in a short period of time. Hyaluronidase (an enzyme that breaks down HA to facilitate its elimination) is available as well as other treatments depending on the adverse effect.
Fillers injection is both art and science. Having a knowledgeable and experience doctor performing the treatment greatly increases results and minimizes risks.
Last update: 16/05/2018