ASSESSMENT OF MAXILLARY TRANSVERSE CHANGES AFTER RAPID MAXILLARY EXPANSION WITH A CUSTOMIZED 3D-PRINTED TOOTH-BORNE EXPANDER IN GROWING PATIENTS: A CBCT STUDY
Keywords:
CBCT imaging, Digitally designed metal-printed tooth-borne expander, Rapid maxillary expansion, Transverse expansionAbstract
The digitally designed and 3D-printed orthodontic expander is a customized tooth-borne appliance used for maxillary and maxillary dental arch expansion in patients with confirmed transverse maxillary constriction. This appliance is relatively new, and its clinical performance, advantages, and limitations have not yet been sufficiently investigated. Therefore, the aim of the present study was to evaluate the changes occurring in different regions of the maxilla and the maxillary dental arch following treatment with a 3D-printed metal expander.
A prospective clinical epidemiological study was conducted on 35 growing patients diagnosed with transverse maxillary deficiency and treated with a 3D-printed metal expander. Measurements were performed on coronal cone-beam computed tomography (CBCT) images of the following parameters: maxillary occlusal width (MxOW), maxillary alveolar width (MxAW), maxillary basal width (MxBW), and upper molar distance (UMD), before and after expansion with the appliance. The data were entered and analyzed using IBM SPSS Statistics version 27.0.1.0, MedCalc version 23.2.7, and Microsoft Excel (Office 2021).
The results demonstrated a statistically significant increase in maxillary basal width (MxBW), with a mean increase of 1.93 mm following rapid maxillary expansion. Maxillary alveolar width (MxAW) increased by a mean of 3.87 mm, which was also statistically significant. A comparable increase was observed in maxillary occlusal width (MxOW), with a mean change of 3.60 mm. The increase in upper molar distance (UMD) following rapid maxillary expansion was 4.26 mm. Based on the findings of the present study, it can be concluded that the digitally designed and 3D-printed tooth-borne metal expander increases the width of both the basal and alveolar regions of the maxilla and expands the maxillary dental arch with minimal side effects related to the inclination of the anchor teeth. The appliance design allows precise positioning of the expansion screw at the level of the center of resistance of the anchor teeth, while the rigidity of the metal minimizes undesirable dental tipping during expansion.
Contemporary clinical practice enables the integration of data from multiple diagnostic examinations, precise digital appliance planning, accurate positioning of the expansion screw, monitoring and assessment of midpalatal suture maturation, and, based on these findings, the fabrication of a fully individualized orthodontic expander.
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