AP, et al: Eur J Orthod 2009; 31 (August): 425-431 In a recent study by Strahm et al, a treatment strategy is investigated that was specifically designed to move lower incisors forward bodily; however, careful observation showed only incisor tipping, with no measurable forward movement of the incisor root apices. Background: Debate exists over whether lower incisors can be moved forward bodily if proper labial root torque is applied. Objective: To measure the change in lower incisor position

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... n a treatment strategy is employed specifically designed to move the lower incisors forward bodily. Design: Retrospective study using existing patient records. Participants: 27 Class II patients (mean age, approximately 10 years) with retruded lower incisors that were treated with mechanics designed to bodily move the lower incisors forward were included. The comparison group was 26 age-matched patients who had similar malocclusions, but were treated in a more conventional manner. Methods: All subjects had cephalograms before treatment (T1), after the first phase of treatment (T2), and at the completion of fixed appliance treatment (T3). The cephalograms were traced and measured to investigate the change in lower incisor position. Interventions: The experimental group had first phase treatment designed to move the lower incisors forward bodily. This was attempted with a lower 2 x 4 appliance exerting labial root torque on the incisors and a reverse headgear (RHG) pulling forward on the lower arch. The comparison group had a conventional headgearactivator treatment during Phase I. Both groups had full-fixed orthodontic treatment to complete the treatment. Results: The lower incisors in the experimental group were tipped forward despite the efforts to move them bodily with labial root torque. No forward movement of the lower incisor apex could be measured. Conclusions: Despite a deliberate attempt to move lower incisors forward bodily, only tipping movements were seen. The width of the lower anterior apical base should not be viewed as changeable during orthodontic planning. Reviewer's Comments: This study gives some support to those who would say bodily advancement of the lower incisors is not possible. Despite efforts by the clinician to place labial root torque and an advancing force on the lower arch, only tipping was seen. On the other hand, the force system in this case was not well controlled and it could be that the practitioner was just not successful in applying the forces that were envisioned. At any rate, at this time it seems prudent to plan orthodontic treatment with the understanding that the lower incisor apex will not move forward. (Reviewer-Brent E. Larson, DDS, MS).