Related Experiment Video
Updated: Aug 28, 2025

Studying Orthodontic Tooth Movement in Mice
Published on: August 2, 2024
Examination of factors affecting condylar bone changes following surgical-orthodontic treatment
Satoshi Endo1, Kanae Niimi1,2, Yusuke Kato1,3
1Division of Reconstructive Surgery for Oral and Maxillofacial Region, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, Niigata City, Japan.
Objective:
To identify factors affecting condylar bone changes following surgical-orthodontic treatment.
Methods:
A total of 200 patients with dentofacial deformities were classified into skeletal Classes I, II, and skeletal Class III groups consisting of 61 and 139 subjects, respectively. Temporomandibular joints (TMJs) were evaluated using clinical findings and computed tomography images before treatment, immediately before surgery, and 6 months after surgery.
Results:
Condylar bone changes occurred at a significantly higher rate after surgery in both groups. Factors related to condylar bone changes following surgical-orthodontic treatment included skeletal Class I or II, disc displacement, and condylar bone changes before treatment. There were three cases with condylar bone changes after surgery that were diagnosed with condylar resorption and skeletal Class II and anterior disc displacement before surgery.
Conclusion:
Condylar resorption could occur when the load on the condyle increases after orthognathic surgery and exceeds the permissible limit.
Related Concept Videos
Bone Disorders
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...
Changes in the Appendicular Skeleton with Age
Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...
Fractures: Bone Repair
Minor fractures with no bone displacement are treated by immobilizing the fractured bone using a cast or splint. However, in the case of fractures with displaced bones, the broken bones are repositioned before immobilization to ensure successful healing without deformation and loss of function. The realignment of fractured bone ends is performed through a process called reduction. If the...
Bone Remodeling
Osteoclasts in Bone Remodeling

