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Updated: Jul 18, 2026
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Measuring Maxillary Posterior Tooth Movement: A Model Assessment using Palatal and Dental Superimposition
Published on: February 23, 2024
Sex differences in mandibular movements during opening and closing.
R P Lewis1, P H Buschang, G S Throckmorton
1Department of Orthodontics, Baylor College of Dentistry, The Texas A & M University System, Dallas, TX 75246, USA.
Summary
Men exhibit greater maximum jaw opening and condylar translation than women, with differences influenced by mandibular size. Incisor movements do not predict condylar translation, suggesting distinct anatomical variations.
Area of Science:
- Biomechanics
- Human Anatomy
- Orthodontics
Background:
- Understanding sex differences in temporomandibular joint (TMJ) function is crucial for diagnosing and treating related disorders.
- Previous research has indicated potential variations in jaw movements between sexes, but detailed 3D kinematic analysis is less common.
Purpose of the Study:
- To quantitatively evaluate sex differences in maximum 3-dimensional (3D) jaw opening and closing movements.
- To investigate the relationship between incisor movements, condylar translation, and mandibular size in men and women.
Main Methods:
- Optoelectric jaw-tracking system used to record 3D condylar (hinge axis) translation and mandibular incisor movements.
- 29 men and 27 women with normal occlusion and TMJ function performed maximum opening/closing cycles.
- Analysis focused on vertical and anteroposterior components of movement, straight-line distances, and curvilinear pathways.
Main Results:
- Significant sex differences observed in incisor opening/closing movements (vertical component) and condylar translation (anteroposterior component).
- Males demonstrated larger incisor movements (52.1 mm straight-line, 54.8 mm curvilinear) and condylar translation (15.4-17.6 mm straight-line, 20.5-20.7 mm curvilinear) compared to females.
- Mandibular length influenced incisor opening and condylar translation differences; condylar pathways differed significantly in shape between sexes.
Conclusions:
- Significant sex differences in incisor movements are independent of mandibular size.
- Sex differences in condylar translation are dependent on mandibular size.
- Incisor movements are not reliable indicators of condylar translation.
- Differences in condylar pathway shapes suggest sex-specific variations in articular eminence morphology.
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