[The behavior of the lower front teeth after systematic extraction of the upper premolars].

Narrowly spaced frontal teeth in the lower jaw have been the object of repeated discussions in the orthodontic literature. There are a number of factors which either directly or indirectly cause the space between frontal teeth in the lower jaw to become narrower and narrower in the course of life. The purpose of the present work was to find out whether orthodontically indicated extraction of premolare in the upper jaw may, in the case of distal occlusion, result in the space between front teeth in the lower jaw becoming narrower and narrower.