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Updated: Jun 30, 2026
Author Spotlight: 3D Movement Assessment of Maxillary Posterior Teeth in Clear Aligner Treatment
Published on: February 23, 2024
Comprehensive three-dimensional analysis of alveolar bone adaptation and root resorption following premolar
Hasan M Sharhan1,2, Hanan Al-Fakeh3,4, Huda M Sharhan4
1Department of Orthodontics, School and Hospital of Stomatology, Shenyang Clinical Medical Research Center of Orthodontic Disease, China Medical University, Nanjing North Street 117#, He-Ping District, 110002, Shenyang, China.
Aims:
This study aimed to assess the three-dimensional effects of orthodontic premolar extraction in Class II division 1 malocclusion cases treated with fixed appliances on maxillary bony changes (alveolar bone thickness and height) and maxillary dental changes (root length and tooth volume).
Methods:
This retrospective cohort study was conducted with 50 adult patients (aged 18-35 years) who underwent orthodontic treatment with fixed appliances and extraction of four first premolars. Pre and post treatment cone beam computed tomography scans were analyzed to obtain quantitative measurements of alveolar bone height and thickness, as well as root length and tooth volume.
Results:
There were significant post-treatment reductions in alveolar bone height in almost all teeth, as well as the cervical alveolar bone thickness, particularly on the palatal side of the anterior teeth. Root resorption was evident across all teeth, and central incisors showed the most significant reduction in root length. Tooth volume decreased significantly across all dentitions.
Conclusions:
Premolar extraction in orthodontic treatment is associated with significant changes in alveolar bone height, thickness, root resorption, and tooth volume, particularly in the anterior maxillary region.
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