INJECTABLE FILLERS
In the last few years an increasing number of injectable wrinkle filling agents (fillers) have been developed and approved for use in Europe . Most of these fillers consist of various types of 'hyaluronic acid', which is found naturally in the supporting framework of the skin. The majority of these fillers are classified as being semi permanent or temporary i.e. they are gradually degraded and absorbed by the body.
Permanent injectable fillers have been used for many years particularly for the lower part of the face. It is currently considered by most medical practitioners that permanent injectable fillers should not be used to treat facial lines and wrinkles because of possible long-term risks.
TEMPORARY FILLERS
Ideally, a temporary wrinkle filler should not cause allergies, not move from its original placement, be safe, injectable through a very fine needle to minimise discomfort, undetectable once in place and be long lasting to maximise benefit as well as to minimise cost. At present no filler satisfies all these criteria completely.
There are currently over two hundred different temporary fillers available and not all have been adequately tested or approved by their national regulatory bodies. The commonest ones currently used in the UK are described below. New fillers are constantly being introduced.
Some of the commoner ones used by the Centre.
Hyaluronic acid gel
Hyaluronic acid is a natural material present in all connective tissue and has been developed as a filling agent similar to collagen and used in the same way but with the benefit of not requiring a skin test.
The commercially available products are either extracted from rooster combs or more recently as a synthetic (manufactured in the laboratory) formulation that is claimed to offer longer lasting results. This product is also available in different strengths, which are recommended to treat different problems.
Restylane gel (Produced by Q-Med Esthetics) is synthetic hyaluronic acid (produced in the laboratory and therefore of non animal origin), which is stable and biodegradable.
After injecting it into skin, the gel binds with water and remains in place for many months. Being synthetic and non animal in origin there is no risk of transmitting disease or developing an allergic reaction in those sensitive to common foods such as beef, chicken and eggs.
The three types available Restylane, Restylane Touch and Restylane Perlane are designed for different purposes and effects from eliminating fine lines to deeper wrinkles to enhancing facial contours eg cheeks.
The effects of the injection last several months. The duration of action is unique to a particular individual and depends on inherent genetic factors as well as age, skin type, life style, and muscle activity in addition to the injection technique.
Injections are performed using local anaesthetic creams or nerve blocks to numb the area beforehand. Afterwards temporary swelling, redness & discomfort can occur. In extremely rare cases an allergic reaction can occur which responds well to the appropriate treatment.
Hylaform ( another form of stabilised hyaluronic acid) is derived from rooster combs and currently comes in three forms, Hylaform Fineline, Hylaform and Hylaform Plus. The mode and duration of action is similar to Restylane. As with Restylane a preliminary skin test is not required.
Fat transfer
Fat transfer has been extensively used for many years to fill out a variety of contour defects on the surface of the body. It is especially useful in correcting facial defects from whatever cause. The abundant blood supply of the face makes it an ideal area to support and maintain the viability of free transplanted fat. In addition, as fat is the body's own tissue, there is no danger of rejection.
The commonest cause of a facial defect is a result of ageing. Here there is usually a loss of fat under the skin at various sites, the commonest being the nasolabial furrows, which develop from the base of the nose to the outer edges of the lip.
Technique : Fat transfer is usually performed on an outpatient basis under local anaesthetic. The donor and recipient sites are numbed with local anaesthetic.
Using specially designed cannulae (small, narrow, blunt surgical tubes) attached to a syringe, fat is painlessly aspirated (harvested) from the donor site into a syringe. This fat is then washed and carefully prepared for transfer into the recipient site. Donor fat is commonly obtained from fat in the stomach, thighs or buttocks.
Transfer is achieved by injecting the prepared harvested fat from a syringe into the numbed recipient site using a specially designed blunt cannula. Because the incisions are so small sutures are not required.
Postoperative sequelae Bruising and swelling can occur for a few days after and infection is rare.
Results Some of the transplanted fat will be absorbed soon after transfer. Some will be absorbed at a later stage and the remainder will take and continue to thrive as normal living tissue. It is however not possible to accurately predict how much fat will take and a second procedure is sometimes required within a few weeks. Results can last several years.
PERMANENT FILLERS
Permanent injectable fillers have been used for many years particularly in the lower part of the face. Ideally a permanent filler should not cause tissue reactions, be easy to inject, feel natural and be readily removable should the need arise.
Fears have arisen regarding the long-term effects of such fillers. Once injected, the body often forms significant scar tissue around the injected substance making removal extremely difficult without producing noticeable scarring. In addition, hardness over the injected area is common.
Some products have been shown to migrate in time and some form significant lumps which require removal. If a defect has been over corrected it cannot be rectified easily and will remain.
Bio-Alcamid. At the present time the only permanent injectable substance which in our opinion, satisfies most of the above beneficial criteria of a permanent filler is Bio-Alcamid, a synthetic gel polymer comprising of acryl derivatives (4%) and water (96%).
Once injected, Bio-Alcamid, becomes covered by a very thin collagen capsule, which completely surrounds the gel, making it an endogenous prosthesis, which can be removed if necessary.
It is used to correct soft tissue defects as well as filling out facial lines and wrinkles and enhancing facial features e.g. chin, cheeks.