Introduction: Temporary Anchorage Devices (TADs) and Cone-Beam Computed Tomography (CBCT) are two developments that have recently emerged in orthodontics. Precise planning and placement of miniscrews is important to avoid damage to critical anatomic structures and to decrease failures. The goal of this study was to evaluate the reliability of a new technique using CBCT data for the safe placement of miniscrews in interradicular areas.
Methods: The placement site on a typodont model was planned by triangulating two dental landmarks to the desired placement location on the CBCT volume. Subsequently, a custom wire guide was fabricated for use as an intraoral guide. Miniscrews (n=64) were placed in interradicular sites between maxillary posterior teeth with (n=32) and without (control, n=32) the wire guide. Placement success was judged by root proximity on CBCT images and categorized as either contacting a root, within .9mm, or at least 1mm clearance.
Results: Using the wire guide 26/32 (81.3%) were placed successfully while 13/32 (40.6%) were successfully placed in the control group. Root proximity using the wire guide was 1.25mm +/-.53mm while the control group was 0.58mm +/-.49mm. These values were statistically significant at (p<.01).
Conclusion: CBCT analysis can provide vital data that can be transferred to the placement site using a simple wire guide. This study demonstrated that miniscrews can be placed safely and reliably using a triangulation wire guide technique.