Approximation and contact of the maxillary central incisor roots with the incisive canal after maximum retraction with temporary anchorage devices_ Report of 2 patients

498 Chung, Choi, and Kim
Fig 5. Postretention intraoral photographs, radiographs, and cephalometric superimposition.
Fig 6. The 3D CBCT superimposition immediately after and 36 months after treatment. These images
were superimposed by automatic voxel-by-voxel registration at the cranial base. No changes were
noted in the surrounding alveolar bone, the position of the central incisors in contact or approximation
with the incisive canal, or the incisive canal itself. A, Sagittal plane, B, coronal plane, and C, axial plane
indicating the incisive canal. Gray, Immediately after treatment; yellow, 36 months after treatment;
arrows, the incisive canal.
factors were equal between both central incisors, supporting
the involvement of the incisive canal. The incisive
canal is a structure that transmits soft tissues such as vessels
and nerves but is surrounded by a thick layer of
cortical bone. Thus, the mechanism of root resorption
for patient 1 may be similar to the condition when the
roots are in contact with or near the cortical plate. 15,16
Unlike patient 1, in patient 2, the involvement of the
incisive canal in root resorption could not be
determined per se. But patient 2 also illustrates the
September 2015 Vol 148 Issue 3
American Journal of Orthodontics and Dentofacial Orthopedics