Crowding or spacing of the teeth can be caused by anatomical abnormalities in jaw structure, disparities between the upper and lower jaw during growth, or traumatic injuries affecting the jaw. An inconsistency in jaw length or width can result in an imbalance of facial bones, muscles, and teeth alignment. An orthodontist can reposition the jaw during childhood so that proper teeth and bone alignment occurs as growth continues, but if issues are not addressed then they can require jaw surgery later. Tooth crowding occurs when there is not enough space for all teeth, which can cause teeth to become crooked, twisted or grow in improper locations and be difficult to clean, increasing risks of dental issues.