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Updated: Jul 8, 2026
Systematic Assessment of Mammalian Skull Specimens for Dental and Temporomandibular Joint Pathology
Published on: August 22, 2022
Relationship of TMJ osteoarthritis / osteoarthrosis to head posture and dentofacial morphology
H Ioi1, R Matsumoto, M Nishioka
1Department of Orthodontics, Faculty of Dentistry, Kyushu University, Fukuoka, Japan. ioi@dent.kyushu-u.ac.jp
Objective:
The purpose of this study was to test the hypothesis that there is a relationship between the temporomandibular joint (TMJ) osteoarthritis/osteoarthrosis (OA), head posture and dentofacial morphology.
Design:
Case-control study.
Subjects And Methods:
The subjects consisted of 34 Japanese females with TMJ OA (aged 24.7 +/- 6.1 years) and a control group of 25 healthy Japanese females (aged 23.6 +/- 1.3 years). Six cranio-cervical angular measurements were constructed for head posture analysis. Nine angular and three linear measurements were constructed for the skeletal hard tissue analysis. Five angular and one linear measurements were constructed for the dental hard tissue analysis. Unpaired t-tests were used to compare the mean differences of head posture measurements and dentofacial cephalometric measurements between the TMJ OA and the control group.
Results:
The TMJ OA group had significantly larger cranio-cervical angles (p < 0.05) and had more posteriorly rotated mandibles (p < 0.0001) than those in the control group. They also had a significantly shorter posterior facial height (p < 0.0001). The TMJ OA group had more retroclined lower incisors (p < 0.05).
Conclusion:
These results suggest that an association may exist between TMJ OA, head posture and dentofacial morphology.
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