Related Experiment Video
Updated: Sep 12, 2025

Systematic Assessment of Mammalian Skull Specimens for Dental and Temporomandibular Joint Pathology
Published on: August 22, 2022
Prognosis and Factors Influencing Temporomandibular Joint Degenerative Disease in Adolescents: A Retrospective Study
Yi-Shu Liu1,2,3,4, Jie Lei2,3,4,5,6, Wei-Yu Mao2,3,4,5,6
1Department of Stomatology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
Background:
Few studies have addressed the prognosis of temporomandibular joint degenerative joint disease (TMJ-DJD) in adolescents.
Objective:
To retrospectively analyse clinical and imaging data of adolescent patients (10-19 years) with TMJ-DJD who had multiple follow-up visits, focusing on condylar bone outcomes and influencing factors.
Methods:
Clinical records and CBCT scans of adolescent TMJ-DJD patients were reviewed. The condylar surface was divided into nine regions to assess the severity of and changes in TMJ-DJD. Bone outcomes (improvement, no change, worsening) at different follow-up intervals (3-6, 7-12, 13-24 months and over 24 months) were analysed for early- and late-stage TMJ-DJD. Logistic regression was employed to identify key factors affecting bone changes.
Results:
In total, 378 patients (62 males and 316 females; 15.36 ± 2.29 years) were included. The proportions of improvement, no change and worsening were 46.8%, 35.7% and 17.5% at 3-6 months follow-up, respectively. After over 24 months of follow-up, these proportions shifted to 64.5%, 18.1% and 17.4%. A significantly greater proportion of early-stage patients than that of late-stage patients improved: 56.5% vs. 34.5% at 3-6 months and 77.4% vs. 56.5% at over 24 months, respectively (p = 0.0167). Late-stage DJD yielded a greater proportion of stable bone conditions. Logistic regression indicated that unilateral involvement (OR = 2.323, p = 0.005) and anterior repositioning splint (ARS) combined with manual disc reduction (OR = 2.785, p = 0.045) significantly influenced bone outcomes.
Conclusion:
Adolescent TMJ-DJD patients show a progressive improvement in bone outcomes. Early-stage TMJ-DJD exhibits more significant improvement compared to late-stage TMJ-DJD, which tends to remain stable. Unilateral TMJ-DJD and ARS significantly enhance bone improvement.
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...
Teeth
In the bud stage, the tooth germ (an aggregation of cells) starts to form in the developing jawbone. During the cap stage, the tooth germ differentiates into enamel organ, dental papilla, and dental sac, which will later develop into the tooth's enamel, dentin...
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...

