As subcutaneous fat accumulates, dimpling, or cellulite, becomes more apparent on the thighs and buttocks. Annular cutters help make holes in pipe and tubes without dimpling and deburring. Carcinomas can also decrease the length of Cooper's ligaments leading to a dimpling. Dermatofibromas typically have a positive "buttonhole sign", or central dimpling in the center. Dimpling of the skin and nipple retraction are not typical features of gynecomastia. There are two processes for producing formed countersinks&colon; "coin dimpling" and "modified radius dimpling".