Many people use silicone injections to plump their lips or to reduce the appearance of wrinkles. But dermatologists say some patients, particularly those who had the injections long ago, are having problems with the silicone hardening and becoming more pronounced over time. Some older women now have ridges where they once had wrinkles, since their skin has thinned but the silicone has not. In this article, a reporter talks to experts about silicone injections, giving information about the...