The concept of bimaxillary transverse osteodistraction: a paradigm shift?

Severe crowding due to narrow upper and lower apical bases can be corrected by the extraction of four premolars, or by bimaxillary transverse osteodistraction. The first strategy is prone to unaesthetic changes in lip posture, nasolabial angle and buccal corridors. Life-long retention is necessary because of the known correlation between increased intercanine distance and relapse of crowding. The second strategy involves surgery and the final outcome regarding stability is not yet known. Theoretically, because the canines have not been moved outside of the skeletal envelope, and because the functional matrix positively influences the dental arches, relapse of crowding should be less. Facial appearance is improved because of the reduction of the buccal corridors and the fullness of the mouth both at rest, and upon smiling.