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Published on: April 15, 2021
Skeletodental and soft tissue changes following treatment with herbst and pendex appliances: a retrospective CBCT
Brianna Tucker1, Jessica Kang1, Christopher Hudson-Boyd2
1Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Philadelphia, PA, USA.
Objectives:
To compare skeletodental and soft tissue changes in growing Class II patients treated with Herbst or Pendex appliances, followed by fixed edgewise appliances, using two-dimensional lateral cephalometric radiographs extracted from three-dimensional cone-beam computed tomography scans.
Materials And Methods:
Forty-six patients were examined: 23 treated with Herbst (12.07 ± 1.49 years, 12 males/11 females) and 23 with Pendex (11.76 ± 1.18 years, 10 males/13 females). CBCT-derived lateral cephalograms were analyzed at T1 (initial), T2 (6 months post-Herbst removal or immediately post-Pendex removal), and T3 (final records after edgewise fixed appliance removal). Cephalometric analysis assessed skeletal, dental, and soft tissue changes. Repeated measures ANOVA analyzed within-group changes across the three time points, and t-tests were used to compare between-group differences at each time point and evaluate changes from T1 to T3.
Results:
From T1 to T3, the Herbst group exhibited a significant decrease in the SNA angle, a non-significant increase in SNB, and significant increases in mandibular dimensions, including total length, body length, corpus length, and ramus height. In contrast, the Pendex group demonstrated stable SNA values, a significant increase in SNB, and mandibular dimensional changes comparable to those observed in the Herbst group. Vertically, both groups remained stable with no significant differences in skeletal vertical parameters. Overall, no significant between-group differences were observed in skeletal, dental, or soft tissue parameters between T1 and T3.
Conclusion/Clinical Relevance:
We did not detect statistically significant differences in overall skeletal, dental, and soft tissue changes between the two groups.

