Losing teeth in a dream is one of the most universally reported dream experiences on record — it shows up across cultures, in dream-psychology surveys, and in casual conversation everywhere, which makes it a genuinely useful example of how the same dream can carry a completely different meaning depending on which tradition you ask.
Outside Korea, the pop-psychology reading you'll most often hear ties the dream to anxiety about aging, appearance, or a loss of control — a reading that leans personal and psychological. Traditional Korean 해몽 goes somewhere else entirely: a tooth falling out is read as being about family, specifically about the health or wellbeing of a relative, not about the dreamer's own body or self-image at all.
Which tooth matters. Losing a front tooth is traditionally read as concerning a closer relative — a parent or sibling — while a side or back tooth points toward a more distant relative. How the tooth comes out matters just as much: a clean, painless loss is read far more gently than a bloody or painful one, which traditional interpreters treat as a more serious warning worth paying real attention to.
It's worth being gentle here, because this is a dream a lot of people have repeatedly and it can sit uneasily afterward if you take the traditional reading at face value. The cross-cultural, non-folklore explanation is worth knowing too: teeth dreams are strongly associated with actual nighttime teeth-grinding (bruxism) and ordinary stress, which is almost certainly why the dream is so common in the first place, in Korea and everywhere else. The two explanations aren't in real conflict — a culture can build meaning on top of a dream that also has an ordinary physical cause.
If you've had this dream, both things can be true at once: it might be nothing more than a stressful week and a clenched jaw, and it's also completely reasonable, if it's nagging at you, to call the relative it made you think of. That's the honest, useful version of the tradition — not a prediction, but a nudge toward a phone call you might have been meaning to make anyway.