Fig. 3

Comparisons of the three-dimensional forces in groups B1 and B2. A Forces in the buccolingual direction. B Forces in the mesiodistal direction. C Forces in the vertical direction. Group B1,anterior teeth inwardly retracted by 0.25 mm, posterior teeth in Andrews’ standard torque group; Group B3: anterior teeth with 0.25 mm of internal retraction and posterior teeth with 5°crown lingual to buccal torque group; Group B4: anterior teeth with 0.25 mm of internal retraction and posterior teeth with 10° crown lingual to buccal torque group.*:P < 0.05