Mandibular Biomechanics and Development of the Human Chin

@article{Ichim2006MandibularBA,
  title={Mandibular Biomechanics and Development of the Human Chin},
  author={Ionut P Ichim and M.V. Swain and Julius A. Kieser},
  journal={Journal of Dental Research},
  year={2006},
  volume={85},
  pages={638 - 642}
}
The development of the chin, a feature unique to humans, suggests a close functional linkage between jaw biomechanics and symphyseal architecture. The present study tests the hypothesis that the presence of a chin changes strain patterns in the loaded mandible. Using an anatomically correct 3-D model of a dentate mandible derived from a CT scan image, we analyzed strain patterns during incisal and molar biting. We then constructed a second mandible, without a chin, by ‘defeaturing’ the first… 
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72 Citations

Why do humans have chins? Testing the mechanical significance of modern human symphyseal morphology with finite element analysis.
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The results of this study corroborate prior hypotheses about the mechanical effects of the human chin and vertical symphysis orientation and support the idea that the relative importance of wishboning and vertical bending in the coronal plane might have played a role in the evolution of modern human symphyseal morphology.
Chin development as a result of differential jaw growth.
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  • Medicine
    American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics
  • 2011
Symphyseal surface strain during in vitro human mandibular wishboning.
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Human symphyseal form, with its distinctive chin, is unlikely to be adapted for countering wishboning loads, which runs counter to the optimality criterion typically invoked in assessing trait performance for signs of adaptation.
When anthropological considerations influence our attitude about the chin and orthognathic surgery
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Recent research based on the analysis of stress using the finite element method (FEM) seems to establish that the presence of the chin is a biomechanical consequence of skeletal and muscular equilibrium peculiar to the human face.
The ontogeny of the chin: an analysis of allometric and biomechanical scaling
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It is indicated that ontogenetic increases in chin projection do not provide greater bending resistance to the mandibular symphysis, and a complex interaction between symphyseal ontogeny and bending resistance is suggested.
Functional significance of strain distribution in the human mandible under masticatory load: numerical predictions.
Numerical and Experimental Models of the Mandible
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This study proved that FE models of the mandible can reproduce experimental strains within an overall agreement of 10% and can be used for the design of a novel TMJ implant considering other load configurations and bone mechanical properties.
Design and Finite Element Analysis of Mandibular Prosthesis
Many reconstructive surgeons are confronted with difficult issues when it comes to defect repair. It is not only necessary to repair the implant during the reconstruction, but it is also necessary to…
Biomechanical Analysis of Patient-Specific Temporomandibular Joint Implant and Comparison with Natural Intact Jaw Bone Using Finite Element Method
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It is observed that the natural TMJ has a higher deformation value as compared to the patient-specific TMJ implant due to the lower mechanical strength of bone relative to the Ti-6Al-4V and Co-Cr alloy, which can conclude that the designed customTMJ implant is safe for the patient from the point of design perspective.
Biomechanical Response in Mandibular Bone due to Mastication Loading on 3-Unit Fixed Partial Dentures
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This study investigates the potential biological remodelling response during mastication on the mandibular pre- and post-insertion of a fixed partial denture (FPD) and suggests similar outcomes to those reported clinically.
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