Why do I get a sore tongue from my retainer?

Your tongue touches the roof of your mouth thousands of times a day, and a wire or plastic edge sitting where the tongue sweeps is a friction machine. The NHS lists minor injuries among the causes of mouth ulcers, and a retainer edge is a repeat injury in the same spot - every swallow, every word, every night - until the tissue breaks down into a small white-grey ulcer with a red, angry border. The first weeks with a new or adjusted retainer are the peak, before the tongue learns to route around it. A rough edge or a wire that has shifted makes it constant. Home care works while you arrange the real fix: orthodontic wax pressed over the offending edge creates an instant barrier (dry the spot first so it sticks), warm salt-water rinses two or three times a day keep the ulcer clean and calm the soreness, and a pharmacy ulcer gel gives numb relief before meals. Take the retainer out for short breaks if your orthodontist's wear schedule allows - but do not stop wearing it entirely without asking, because teeth drift faster than people expect. The real fix is professional and quick: if wax and time do not settle it within a week, or the same spot keeps re-ulcerating, call your orthodontist or dentist - smoothing a wire or trimming an edge takes minutes, and no one should put up with a retainer that injures them. The NHS's general tongue rule applies too: any sore spot that does not heal within about 3 weeks, appliance or not, should be examined. Pymander is a free AI doctor, 24/7 by text, that can help you manage the meantime.