You're having a nice dinner with someone. Let's say someone of the opposite sex. You're talking, then looking down to eat your food, looking back up to talk, when, EWWWW! You see a large speck of something lodged between their front teeth. Thus today's dilemma: How do you tell someone they have something in their teeth?
Well, if you're in a larger group and don't want to embarrass them, you might "eye" them to get their attention, then sorta point at your own teeth to give them the idea.
However, in a one-on-one situation, I think that it all depends on how well you know the person. If you hardly know them at all, then you don't say anything. You have to be comfortable with someone to tell them something this vital. This could also go for people you aren't particularly fond of. lol That way, for the rest of the night, they'd look like a complete moron to others.
If you're pretty good friends, then you might just come out and say it, "You've got something between your teeth." That is loosely translated, "You have a large nasty black something between your teeth and if you don't take steps immediately to extricate it, I may lose my lunch."
And finally, if you really know the person, maybe you've been dating for a year or married for a couple of years or something, you might just reach right over there and pick it out yourself. LOL "Hang on....mmmph... there! Hmmm...Looks like some pepper." (flick it off your finger)
Well, I'm hungry now. Time for lunch. lol
"What's the matter girl? Well don't you think I'm good enough. This old man had a hard time gettin' here. You can leave your number at the door..."