Yeah, is it liquid silicone? How bad are your scars? You would be taking a risk, and if it doesn't come out right, silicone isn't as easy to remove as it is to inject. And insurance probably won't cover the surgery to correct it. Also, won't the facial skin start to sag after a couple of years? Surgeons often tell patients to come back every few years for touch ups on breast implants, so it could be the case for face implants as well.
Also, when you're older and your skin shrinks and sags, won't the injections be more noticeable? I know I'm just answering with a ton more questions, but I guess the best thing to do is more research and to decide if it's REALLY worth the risk. In the meantime, you could look into some natural alternatives to healing your scars. There are tons out there that help. A naturopath can help you with that.
Also, can you post some pictures? It always looks worse to the person who has them than to others. I've seen great looking people who thought they had horrible scars. Truth was, I wouldn't have noticed if they didn't pointed it out. I have some bad scars too if that makes you feel any better.