Hyaluronic acid fillers are said to offer longer lasting results than collagen-based fillers. Restylane and Juvederm are FDA-approved for certain cosmetic purposes and used off-label for others.

This category of fillers is perhaps the most complicated since there are not only fillers, but other materials and methods of fat and dermal-fat transfer to consider. The thickest fillers are better for volume enhancement and are used to treat areas of the face that need to be plumped up.

Of all the available options for substituting deep soft tissue, the naturally occurring hyaluronic acid compounds are the most popular, offer the most advantages, and have the least amount of complications. Sculptra® is a volumetric enhancer that has been approved by the FDA to treat facial wasting syndrome due to the effects of HIV treatment. It works by producing a tissue reaction at the dermal-subcutaneous interface. It usually requires several treatments. It does not provide the instant filling effects of Juvederm Ultra Plus® or Perlane® and is also not permanent, but reports lasting up to 1 – 1 ½ years. Radiesse® is a calcium hydroxyapatite compound which is a substance normally found in bone. It can be used to fill defects over bone. Although Radiesse® claims to last longer, in my experience, it has a tendency to be "bulkier" when injected into the soft tissue without the more natural feel that the hyaluronic acids have to offer. When injected into soft tissue, Radiesse® causes a fibrous capsule to form around the material until it resorbs. It cannot be used in the lips since it produces white nodules which necessitate surgical removal.

Radiesse® has also recently been advertised as a substitute for facial implants; providing a "non-surgical approach for chin or cheek implants". In my opinion, Radiesse or other fillers should not be used for this purpose. Fillers, as opposed to facial implants, do not support soft tissue or provide structure to the facial skeleton. When volumes exceed their intended use, they can cause problems of infection, lumpiness, nodules and soft tissue fibrosis which can only be permanently cured with surgery.

Here are some tips to consider when consulting a doctor:

	Review the doctor's credentials, education, training, type of certification held, and number of times that the treatment has been performed by the doctor.
	Find out the dosage that will be required to achieve a satisfactory result for your condition.
	Ask your doctor to estimate the number of treatments required to maintain the results you are expecting.
	View before-and-after photos of patients who received Restylane and alternative procedures.
	Ask about complication risks and possible side effects, including the impact of smoking.
	Be sure to discuss current medications you're taking and their impact on Restylane treatment.
	Request a list of pre- and postoperative instructions. Following these instructions can reduce the risk of complications.