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Updated: Jun 3, 2026

Measuring Maxillary Posterior Tooth Movement: A Model Assessment using Palatal and Dental Superimposition
Published on: February 23, 2024
3-Dimensional cone-beam computed tomography analysis of transverse changes with Schwarz appliances on both jaws
Kiyoshi Tai1, Jae Hyun Park, Katsuaki Mishima
1Postgraduate Orthodontic Program, Arizona School of Dentistry & Oral Health, A.T. Still University, Mesa, AZ 85206, USA.
Objective:
To evaluate transverse changes from Schwarz appliances on both jaws in young, growing patients using cone-beam computed tomography (CBCT).
Materials And Methods:
All subjects had Angle Class I molar relationships and crowding. They were randomly divided into two groups; 30 expanded and 30 control subjects. Three-dimensional CBCT software was used to evaluate and compare treatment effects between the groups. To test for any significant differences between groups at T0 and T1, an independent t-test and paired t-tests were used.
Results:
The interbuccal dentoalveolar width (BDAW), interpalatal dentoalveolar width (PDAW), and interlingual dentoalveolar width (LDAW) values showed significant changes when measured from a point 3 mm coronal to the cementoenamel junction (CEJ) to 8 mm apical to the CEJ. When compared with mandibular interdentoalveolar width differences (BDAW-LDAW), significant differences (P < .05) were observed. The soft tissue width of the maxillary and mandibular teeth and alveolar bone showed no significant changes (P > .05), even with dentoalveolar arch expansion in both jaws.
Conclusions:
This study indicates that Schwarz appliances primarily affect the dentoalveolar complex and have varying effects on mandibular and maxillary alveolar bone width. Also, soft tissue is not affected in the area of expansion in this research.

