There is a big demand for filling up facial defects, folds, creases and crevices by injecting a substance that will stay there life long and not migrate or cause other problems. Without doubt, thousands of patients have achieved this in the past with a range of substances, from liquid silicone ro hydroxy-apatite or special gels. However, perhaps many more people have come to grief with their use because of the injected materials migrating, initiating nasty tissue responses and disfiguring results. This is why in most countries, for all practical purposes, permanent fillers can no longer be used.
TEMPORARY ONLY
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A BROKEN PROMISE
PERMANENT FILLING SUBSTANCES
DISAPPEARING SUBSTANCES
TWO DISTINCT PROPERTIES
 The injectables that are designed to add volume to the face work on two fronts. On the one hand there is the volume increase by the injected volume itself. Additionally there can be a tissue reaction that stimulates the formation of new tissue on the injected site and adds volume by new tissue generation. All temporary injectables have possess these properties to a certain extend, but are usually designed to promote one or the other principally. We will discuss them in two groups: the filling substances and the tissue stimulators. We shall discuss the use of the patient's own tissue as a third, separate category. |
THE PASSIVE FILLERS
HYALURONIC ACID: A MINIMUM OF TISSUE REACTION
 Basically, of all the substances that have been used to temporarily add volume to the deeper layers of the skin, hyaluronic acid is the one compound that withstood the test of time best. Hyaluronic acid (HA) is also a common compound in other forms of restorative surgery and being used in the treatment of articular resurfacing and treatment of arthrosis. It tends to absorb after topical application on the skin and is therefore a popular ingredient of a variety of cosmetic and skin care products. HA is now the most popular injectable for direct filling of soft tissue defects such as facial wrinkles, tear troughs and lips. Restylane, Juvederm and Teosyal are some of the more common trade names for the product. There effect is temporary by adding volume under the skin. The effects typically last for 6 to 12 months, depending on the viscosity and the volume injected. |
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VOLUME STIMULATORS
INJECTING FOR TISSUE GROWTH
 These dermal fillers provide biocompatibility, durability, efficacy, and ease of use in soft tissue augmentation. The most popular compound is synthetic calcium hydroxylapatite particles (CaHA), composed of calcium and phosphate ions. CaHA occurs narturally in large amounts in the body and is therefore entirely biocompatible. Extensive safety studies show that re-injections at multiple time points are safe because of its: |
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The result is a soft, flexible, longer-lasting correction delivered by the CaHA particles and the body’s natural tissue. Because the adjacent cells become an integral part of the injectable, the final structure is similar to the surrounding tissue. Trials have demonstrated that the CaHA particles in Radiesse™ dermal filler have no tendency to migrate. The structure of CaHA and natural tissue forms a cohesive implant that remains in place for more than one year in many patients. Over time, CaHA particles slowly dissolve and metabolize through the same homeostatic process as that seen with bone fragments from common fractures. The slow, natural process of CaHA degradation provides augmentation durability. The product is 100% biodegradable, hence not permanent. |
