A medical device and methods for filling tissue are disclosed. The device is transformable between a first configuration wherein the device can pass through a small catheter or needle placed in the tissue to be filled and a second configuration in which the device is enlarged within the tissue to be filled. The exterior profile of the expanded device may be customized along its length to achieve a desired result. In one embodiment, the device comprises an outer sleeve having a filler. The device may be used to reduce facial wrinkles or augment facial features such as the lips.