Comparative CBCT and Cephalometric Analysis of Vertical Maxillary Changes with Bonded and Banded Expanders in Adolescents Aged 12-18 Years.

Abstract Objective: This study evaluates the vertical maxillary effects produced by banded and bonded RPEs in 12 to 18 year-old adolescents, comparing the changes obtained by both types of expanders, through CBCT and cephalometric analyses. Methods: Eight articles in adolescents with age ranging from 12 to 18 years were analyzed and applied both Cone Beam Computed Tomography (CBCT) and lateral cephalograms. Outcomes of interests were differences in LAFH, SN-GoGn and the inclination of the occlusal plane. The results were synthesized to express mean with Standard Deviation (SD) and the significance of effect size was examined with p -values and effect sizes (Cohen’s d). The quality of all included studies was assessed by the Cochrane Risk of Bias tool and Newcastle-Ottawa Scale. The protocol for this study has been registered on PROSPERO and the whole protocol is available on request. Results: Bonded tightens achieved significantly smaller vertical effects compared to banded tightens (eg., LAFH: bonded = 0.9±0.4 mm vs. banded = 2.3±0.6 mm; p<0.01, d = 1.27). Bounded expanders had less increase in the SN-GoGn angle (0.7±0.3°) than the banded group (1.9±0.5°, p<0.05, d = 1.05). The CBCT results indicated the amount of the posterior vertical movement and molar tipping in the bonded groups were decreased. Conclusion: In 12-18 year old adolescents, bonded expanders result in more controlled vertical maxillary changes and less mandibular rotation than do banded expanders. Bonded expanders are the method of choice when less than 2 postubes movement is desired. Additional longitudinal study is required to establish the long-term stability of these results.