Silicon patches for scars

I'd be grateful if you could do some research on the Cica-Care system which claims to improve the appearance of scars. I'm considering using it for my seven year old daughter on a scar resulting from heart surgery two years ago. I am particularly interested in any research on its safety and potential side effects. HM, Upper Bangor......

Improving the look of both hypertrophic (enlarged) and keloid (overgrown) scars can be problematic, partly because our understanding of scar formation is not very sophisticated. What is known is that no method can make scars disappear completely, giving rise to the saying, "even plastic surgeons can't erase without a trace". A number of methods are used to prevent scar formation, and to manage new and old scars. These include the use of corticosteroids, laser treatment and cryotherapy, which uses extreme cold to destroy scar tissue. Each of these represents a rather drastic approach to scar management.

The use of relatively non invasive silicone sheeting, such as Cica-Care, is a fairly new phenomenon. With this method, the individual wears a thickish sheet of gel impregnated with silicone for a minimum of 12 hours a day. In reviews of scar management, silicone sheeting has certainly come out as one of the best ways to deal with fresh and chronic scars (Aesthetic Plast Surg, 1994; 18: 307-13).

Skin rashes and superficial maceration (tissue softening) from the use of silicone gel have been reported, although these usually disappear when the treatment is withdrawn. The silicone does not appear to enter the wound site (Dermatol Surg, 1995; 21: 947-51; Surgery, 1989; 106: 781-7), though why this should be is not clear. In fact, what is worrying about this treatment is that it's largely unknown how silicone works to reduce the appearance of scars.

Another study of silicone sheets resulted in moderate improvement of hypertrophic and keloid scars resulting from surgical procedures or trauma. Improvement was noted in scar thickness and colour, and the treatment was considered easy to use, painless and successful in each of the cases (J Dermatol Surg Oncol, 1993; 19: 912-6).

In one longer term study, patients wore the sheets for between 12 and 24 hours a day for at least two months. After six months' follow up, 56 per cent showed improvement of old scars, whereas 79 per cent of fresh scars improved suggesting that the sheeting is most successful when used as soon as possible after the skin is damaged (Cutis, 1995; 56: 65-7).

The big question remains: is it the silicone which is the active ingredient? Several studies suggest that it isn't. One pilot study compared a silicon gel sheeting with a simple "hydrogel" dressing. Effects on both the appearance of the scar and molecular changes in the skin were compared on 15 hypertrophic scars. Both types of sheeting produced similar results, but the hydrating gel produced more positive chemical changes in the skin and was better for long term scars. The silicon showed some advantage in fresh scars (Dermatol Surg, 1996; 22: 955-9).

In another small pilot study, a glycerine based gel sheeting was found to be similarly effective and was also less expensive (Adv Wound Care, 1998; 11: 40-3). Another study compared an occlusive dressing technique (where the scar tissue remains covered for long periods of time) using cream which did not contain silicone oil, with a simple application of Vaseline. In all cases, the cream treated areas of scar and keloid demonstrated a "remarkable improvement over that of the Vaseline treated areas". The authors concluded that the therapeutic action of this method must be due to the hydration and covering up (Br J Plast Surg, 1992; 45: 599-603).

We are aware of only one trial which specifically used Cica-Care, involving 42 patients with hypertrophic scars. Patients were randomly assigned either the Cica-Care sheeting or another silicone gel sheeting. The rate of recovery was found to be the same in both groups, but the Cica-Care sheeting was more adhesive, more comfortable and thus more acceptable to users (Burns, 1994; 20: 163-7).

While the gel is perhaps more pleasant to use, it's not likely to be any more effective than an occlusive dressing with silicone cream, though it will be more effective than cream simply applied to the skin (Br J Plast Surg, 1990; 43: 683-8). Keeping the scar hydrated for long periods of time is what appears to improve the appearance of scar tissue.

The main concern about the use of silicone for any purpose stems from silicone breast implants, which have been linked to a number of debilitating symptoms. Once in the body, silicone can "leak" and migrate to the lymph nodes, which has been shown in women to lead to a higher risk of autoimmune diseases, such as scleroderma, which affects the blood vessels and connective tissues (Lancet, November 28, 1992). Other adverse effects of silicone overload, according to a study by the FDA and University of Maryland School of Medicine, are some forms of sclerosis, characterised by loss of cognitive function and chronic fatigue (Lancet, 1997; 350: 1531-7).

Because your daughter is so young, there is a good chance that the appearance of the scar will improve on its own over time. However, if you are concerned about it, this may be an effective way of approaching the situation. Just be aware that there is no current evidence that silicone sheeting can cause adverse effects on health, largely because such research has not been done.