Normally teeth should be orientated to follow the natural arch. Occasionally a rotated tooth is positioned perpendicular to the normal arch. In the case above not only is the lower fourth premolar rotated but it is a supernumerary (extra) tooth and should be extracted due to crowding which will lead to periodontal disease.

Also referred as a persistent primary tooth, a retained deciduous tooth occurs when the adult (secondary) tooth fails to push the baby (primary) tooth from its socket. Retained deciduous teeth should be extracted to prevent orthodontic and/or periodontal future problems.

Supernumerary teeth occur when one or more extra permanent teeth erupt in the oral cavity. Treatment of choice is to remove the extra tooth giving the normal teeth enough room.

Normally teeth should be orientated to follow the natural arch. Occasionally a rotated tooth is positioned perpendicular to the normal arch. In the case above not only is the lower fourth premolar rotated but it is a supernumerary (extra) tooth and should be extracted due to crowding which will lead to periodontal disease.