Abstract
In the orthodontic assessment of mild malocclusion of the lower arch, the impaction of lower third molars is often ignored. In such cases lower arch alignment is frequently, later, compromised by the continued presence of the impacted third molars. The authors have produced a simple geometric procedure, to be applied to rotated cephalograms, which will enable clinicians to forecast accurately those lower third molars which will reach occlusion, after the extraction of lower second molars. In addition, such extractions will correct mild buccal arch crowding without the use of appliances. Results of the eruptive progress of 50 lower third molars, over a 7 year period, are presented to support the theory.