15 years ago, got medpor implant that was wide and little projection. Exchanged for Allergan size 1 silicone. Last year upgraded to Implantech XL. Looked great but after a month it shifted down losing the projection. Doc refused to use a screw. My issues are not enough projection, implant sits low and musle rides up creating weird look, implant moves, and a little crooked. Would a sliding genioplasty help me? I like a pointier/narrow chin. Worried about damaged muscle and looking weird.