Claim: Husband loses false teeth after prankingly swapping them with his wife's lost dentures.
There is the story of the husband who was always trying to score off his wife. This went on for years until both were middle-aged people. Then on one weekend they went to the beach with friends for the day. Husband was a keen surfer still, and he persuaded his wife to go swimming with him despite the big surf running this particular day. The inevitable happened, and the wife was caught by a dumper and rolled helplessly up the beach. In the process she opened her mouth to shout and lost her false teeth, much to her dismay. Her husband went ostensibly to help her find the missing dentures, along with their friends who accompanied them on the excursion and, winking hugely at them, slipped his own false teeth out and pretended to find them. He offered them to his wife, who rinsed them in the sea and tried to fit them in. They wouldn't fit, of course, and to the husband's horror she flung them far out into the breaking waves, saying, "It's no good, those aren't mine!"
Variations: In some versions a fellow loses his false teeth during a bout of seasickness while on a fishing trip, and his companion ties his own dentures to his fishing line and pretends to "fish" his friend's teeth out of the ocean.
Origins: Many a plot has turned on one person's losing something of importance, while others attempt to replace it with a hastily-obtained look-alike: a deceased pet is swapped for a similar animal procured from a pet store before the
owner finds out that his critter has died; a woman loses a ring of great sentimental value, but helpful friends quickly secure a (usually cheaper) replacement from a local jeweler. The typical denouement to such tales is that the recipient eventually catches on to the deception but is touched that others cared enough to try to make up for his or her loss.
The "Not My Teeth" legend stands such plots on their head: Rather than trying to be helpful in replacing the loss of something important to his wife, a husband cynically tries to one-up her with a crude trick instead, resulting in his suffering an equivalent loss.