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It is not really known exactly why teeth become crooked, as it is not known why teeth begin to erupt. There are some factors that can contribute to crooked teeth, such as thumb sucking at an early age, and disease at an older age. It is often caused by the jaw being too small, which will cause the teeth to be crowded, and subsequently push against each other in crooked directions. This is one of the reasons that wisdom teeth are so troublesome, is that the human jaw has evolved and adapted to be
