Mentor offers saline breast implants and two types of silicone breast implants. The procedure places implants behind breast tissue or under the chest muscle. Mentor MemoryGel Breast Implants are pre-filled with Mentor’s cohesive silicone gel that holds safely and uniformly together to deliver a natural feel that closely resembles breast tissue. After the implant has been placed, the incision is carefully sutured. Mentor Silicone Implants are available in teardrop and round shapes. Teardrop-shaped implants are thinner at the top and gently slope to a fuller projection point near the bottom while round breast implants are circular.