Short of a true vertical lengthening chin implant, no preformed chin implant can create any significant vertical height. You can replace your chin implant with either a better designed one or an opening sliding genioplasty at any time.
Chin implant candidate versus genioplasty
Silastic chin implants are manufactured in a large variety of sizes and shapes, and can be custom carved according to the patient's unique anatomy. Implantech manufactures a very special style chin implant that offers vertical height augmentation, so ask your surgeon about that particular implant. The old implant can be removed and the new one placed under local anesthesia as an outpatient surgical procedure. A sliding genioplasty is usually performed by an oral surgeon under general anesthesia in a hospital setting with an overnight hospital stay. This surgery is much more invasive and is usually done when patients have teeth that do not fit appropriately. Sometimes, the upper and lower jaw has to be broken to get the teeth to fit together properly. For more information and many examples of chin implants, please see the link and the video below
the sooner it is removed, better! Less scar formation around the implant makes it easier to remove. Sliding genioplasty can add width and height to your chin. Jaw surgery is another option.