The design of bone-borne maxillary expander affects the different dentoalveolar inclination and expansion pattern: A CBCT study

Abstract

Objective

This study compared the skeletal and dentoalveolar changes induced by tissue-bone-borne expander (C-expander) and pure-bone-borne expander (ATOZ-expander) using CBCT analysis. We aimed to identify their distinct expansion patterns and potential clinical implications.

Materials and Methods

A total of 60 subjects, comprising 14 males and 46 females with an average age of 18.5 ± 7.36 years, were divided into two groups: the tissue-bone-borne expander group (CEXP group, N = 30, average age 19.16 ± 7.09 years) and the pure-bone-borne expander group (ATOZ group, N = 30, average age 17.83 ± 7.56 years). CBCT scans were obtained before (T1) and after expansion (T2). Zygomatic, palatal, and dentoalveolar dimensions were measured and analyzed using paired T-tests and Kruskal-Wallis tests.

Results

The CEXP group demonstrated significantly greater dental expansion and an increase in dentoalveolar inclination. In contrast, the ATOZ group exhibited significantly less zygomatic expansion and a decrease in dentoalveolar inclination. In horizontal plane, the CEXP group showed more parallel expansion pattern than the ATOZ group. Both groups showed similar amount of palatal expansion.

Conclusion

The tissue-bone-borne C-expander demonstrated more pronounced dentoalveolar effects with a vertically pyramidal and sagittally parallel pattern of expansion. In contrast, the pure bone-borne ATOZ-expander exhibited more substantial skeletal effects with a vertically parallel and sagittally trapezoid expansion.