[AlotOfReading]

The short answer is that we don't know the exact meaning. There are similar finds of dental modifications scattered across the Southwest. However, it's important to note that the Southwest was in active "cultural communication" with its neighboring areas, including Mesoamerica. Plenty of ideas went both ways, especially iconography. People like Lekson are still arguing that Chaco was at least partially an experiment/imitation of more Southern political systems.