dental disorders
Malocclusion
Etiology of Malocclusion
Causes of malocclusion include Size mismatch between jaw and teeth Certain oral habits (eg, thumb-sucking, tongue thrusting) Missing teeth Facial trauma Certain congenital defects Malocclusion most often results from jaw and tooth size discrepancies (ie, the jaw is too small or the teeth are too large for the jaw to accommodate them in proper alignment). People who habitually suck their thumb or push their tongue up against their front teeth may cause gradual protrusion of the upper incisors. When permanent teeth are lost, adjacent teeth may shift and opposing teeth may extrude, causing malocclusion unless a bridge, implant, or partial denture (see Dental Appliances ) is worn to prevent these movements. When children lose deciduous teeth prematurely, the teeth more posterior in the arch or the permanent first molars often drift forward, leaving insufficient space for other permanent teeth to erupt. Malocclusion after Fractures of the Mandible and Midface may indicate tooth displacement and/or alveolar bone or jaw fractures. In ectodermal dysplasia, 