Otoplasty reduces how far the outer ear projects from the side of the head. Prominent ears usually come from an underdeveloped antihelical fold — the ridge that folds the upper ear inward — and an over-deep conchal bowl. Surgery recreates the fold and reduces or repositions the bowl, bringing the helix-to-mastoid distance back to roughly 10–12 mm at the upper third, rising to 20–22 mm at the lobule, so the ear tapers naturally rather than being pinned flat.
The middle and inner ear are untouched, so hearing is unaffected. Results are long-lasting, but reported relapse rates range from roughly 5–20% depending on technique, most often in the first year, and revision is sometimes needed. The aim is symmetry within normal variation, not two identical ears.
Repair of a torn or stretched lobe is a much smaller and completely separate procedure: see ear lobe repair.