By their late teens or early twenties, most people get their third set of molars, commonly called wisdom teeth. When they are properly aligned and healthy, they come in as any other tooth would. More often, however, they’re misaligned and that can cause major problems. They can crowd adjacent teeth, affect your jawbone or nerves, even grow under your other teeth. This can cause bone loss, weakening your jaw if not removed promptly. Even partial eruption gives bacteria an opening in the gums to collect and potentially cause tooth decay or gum disease.