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Updated: Feb 2, 2026

Systematic Assessment of Mammalian Skull Specimens for Dental and Temporomandibular Joint Pathology
Published on: August 22, 2022
Radiographic features associated with temporomandibular joint disorders among African, White, Chinese, Hispanic, and
1Division of Orofacial Pain and Temporomandibular Joint Disorders, Eastman Institute for Oral Health, University of Rochester, NY, USA.
Context:
Various radiographic features have been associated with temporomandibular joint disorders (TMDs); however, these characteristics have not been compared among different racial groups.
Aims:
To radiographically evaluate and compare craniofacial patterns and condylar findings suggestive of TMD among African, White, Chinese, Hispanic, and Indian racial groups.
Settings And Design:
This multicenter retrospective study used data from three private orthodontic practices and a University Orthodontic Clinic.
Subjects And Methods:
Panoramic and lateral cephalometric radiographs were collected from 250 subjects who were equally divided into five racial groups: Africans, Whites, Chinese, Hispanics, and Indians. All radiographs were initial records from patients seeking orthodontic treatment. Linear and angular cephalometric measurements were used to evaluate and compare cephalometric characteristics associated with TMD among groups. Panoramic radiographs were analyzed to compare the presence of condylar abnormalities and antegonial notching among groups.
Statistical Analysis Used:
One-way analysis of variance, followed by Tukey's test.
Results:
African and Chinese groups had the smallest mean cranial base measurements, while the Indians had the largest. The mean Y-axis value was significantly larger in the Chinese group compared with the other groups. Increased mandibular plane angles were seen in the Chinese and African patients, compared with subjects from other groups. The mean percentage of condylar anomalies was higher in the Chinese subjects compared with all other groups.
Conclusions:
Chinese patients presented with more radiographic features suggestive of TMD, whereas the Indians showed the least, compared with subjects from the White, Black, and Hispanic racial groups.
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