Over and under the muscle are the two types of procedure that can be performed when having breast implants. Over the muscle refers to the breast implant being positioned in front of the breast muscle and sits just below the natural breast tissue. This is one of the best options for if you already have a large amount of breast tissue or are restoring fullness to deflated breasts. Under the muscle refers to the breast implant being positioned behind the breast muscle and therefore is further beneath the skin. This is more suitable for women with smaller amounts of breast tissue and provides very natural looking results. Your surgeon will discuss the best method to use to achieve the results you are looking for.