Some Causes of Malocclusion ?

Hereditary : for example, you may inherit your mother's small jaw, and your father's large teeth; if this is the case, your teeth would be too large to fit your jaw.

Trauma : if you lose a tooth due to an accident, then teeth may start to drift into the empty space.

Disease : you can lose a tooth early due to cavities or gum disease; this often leaves a space which other teeth drift towards.

Malnutrition : nutritional deficiencies can alter the growth of the jaws and teeth.

Habits : thumb-sucking can shift the teeth out of alignment.