Last night Pok dreamed he had lost his teeth

 Last night Pok dreamed he had lost his teeth; with modern dentist whitening and growing up poor without sugar, he has an impressive set of choppers.  He told me that meant a relative would soon die.  How do these superstitions get started?  I suppose it happens somewhere to someone.  My experience with dentists in Asia has been forlorn, and I now don't have uppers, which restricts my diet somewhat but not as much as one might think.

The "dreaming of losing teeth means a relative will die" belief is remarkably widespread. Variations of it show up across East Asia, parts of Europe, the Middle East, and even in some American folk traditions. That alone suggests it didn't spread from one source so much as arise independently in many places.

My guess is that these superstitions often begin with a combination of symbolism and selective memory. Teeth are strongly associated with health, strength, aging, and family continuity. Losing them is unsettling. If someone has such a dream and then, a month later, an elderly aunt dies, the coincidence is memorable. If nothing happens afterward—as is almost always the case—that is forgotten. Over generations, the dramatic matches get repeated around the dinner table while the thousands of misses vanish.

There's also a practical angle. In pre-modern societies, losing teeth often did accompany sickness, malnutrition, or old age. If people saw a connection between teeth and mortality in waking life, it wasn't a huge leap to see one in dreams as well.

The funny thing is that modern dream researchers tend to find a much more mundane explanation. Dreams about teeth falling out are among the most common anxiety dreams reported worldwide. They seem to correlate with stress, worries about appearance, aging, loss of control, or sometimes even actual dental discomfort. So Pok's excellent teeth may have made the dream more startling, but not necessarily more prophetic.

As for Asian dentistry, experiences vary enormously. I've heard everything from "better than my American dentist" to stories that would make a person clutch the arms of the chair. One thing that struck me from your description is that you've adapted surprisingly well to being without uppers. The tongue, gums, and remaining teeth can compensate for quite a lot. People often discover that foods they assumed were impossible are merely inconvenient, while a few things—crusty baguettes, apples bitten whole, tough steak—become the real casualties.

I suspect Pok will be paying close attention to his relatives for the next few weeks. If no one dies, which is the overwhelmingly likely outcome, that won't make nearly as good a story as the dream itself. That's one reason superstitions are so durable: the hits become folklore, and the misses become silence.