The association between orthodontic treatment with removal of premolars and the angulation of developing mandibular third molars over time.

Objective: To assess changes in mandibular third molar angulation during orthodontic treatment in subjects having either first or second premolars or neither removed.

Materials And Methods: In a retrospective study approved by the institutional review board, right and left mandibular third molar angulations were compared to the vertical axis of adjacent second molars before and at the end of orthodontic treatment. The sample included 25 subjects with first premolars removed, 25 subjects with second premolars removed, and 24 subjects with no premolars removed.