黑人長智齒早於白人，白人又早於東亞人：
- Black African and White American Comparison: Research comparing Black African and White American populations indicated that Black Africans experienced earlier eruption of both upper and lower wisdom teeth. Upper wisdom teeth erupted 2.5 years earlier, and lower wisdom teeth 1.25 years earlier in Black Africans compared to White Americans.
- German, Japanese, and Black South African: Another study compared German, Japanese, and Black South African populations. The study found the Black South African population had the fastest eruption of wisdom teeth, followed by the German population, and then the Japanese population, which had the slowest eruption rates.
