What actually differs between implants over and under the muscle?
The pectoral muscle either covers the implant or does not — changing camouflage, movement with exercise, and the feel of early recovery.
Over the muscle (subglandular) places the implant between gland and pectoral muscle; under the muscle (submuscular or dual plane) slides its upper portion beneath the pec. The single anatomical difference drives most of the practical ones.
What each placement trades
Under the muscle, the pec adds a covering layer over the upper pole — softening the implant border and reducing visible rippling — but flexing the chest can shift or distort the implant, the movement called animation. Over the muscle avoids animation and tends to have an easier early recovery, but demands enough natural tissue to hide the implant on its own.
Dual plane splits the difference — muscle over the top, gland over the bottom — and has become the common middle path. The deciding inputs are the pinch thickness of tissue in the upper chest and how the patient uses their chest muscles, both of which vary by individual and belong in a specialist consultation.
MediIndex articles are for general information only and are not medical advice, diagnosis, or advertising. Outcomes vary by individual — consult a board-certified specialist for personal decisions.