A third molar that fails to fully enter the mouth (erupt) because it is blocked by another tooth, bone, or soft tissue. This happens because modern human jaws are often too small to accommodate 32 teeth.
Partial impaction creates a flap of gum tissue (operculum) that traps food and bacteria, leading to a painful infection called Pericoronitis. Fully impacted teeth can develop cysts that damage the jawbone.
A "stuck" wisdom tooth that cannot break through the gums properly.
You often cannot see it. If partially erupted, it looks like a small white point of enamel poking through swollen, red gum tissue at the very back of the mouth.