Structural and mechanical properties of mandibular condylar bone.
The trabecular bone of the mandibular condyle is structurally anisotropic and heterogeneous. We hypothesized that its apparent elastic moduli are also anisotropic and heterogeneous, and depend on trabecular density and orientation. Eleven condyles were scanned with a micro-CT system. Volumes of interest were selected for the construction of finite element models. We simulated compressive and shear tests to determine the principal mechanical directions and the apparent elastic moduli. Compressive moduli were relatively large in directions acting in the sagittal plane, and small in the mediolateral direction. The degree of mechanical anisotropy ranged from 4.7 to 10.8. Shear moduli were largest in the sagittal plane and smallest in the transverse plane. The magnitudes of the moduli varied with the condylar region and were proportional to the bone volume fraction. Furthermore, principal mechanical direction correlated significantly with principal structural direction. It was concluded that variation in trabecular structure coincides with variation in apparent mechanical properties.
van Eijden
T M G J
TM
Department of Functional Anatomy, Academic Centre for Dentistry Amsterdam, Universiteit van Amsterdam and Vrije Universiteit, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands. t.m.vaneijden@amc.uva.nl
van der Helm
P N
PN
van Ruijven
L J
LJ
Mulder
L
L
D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena; D015519:Bone Density / Q000502:physiology; D019245:Compressive Strength; D003198:Computer Simulation; D004548:Elasticity; D005260:Female; D020342:Finite Element Analysis; D006801:Humans; D008297:Male; D008335:Mandibular Condyle / Q000033:anatomy & histology* / Q000502:physiology; D008852:Microradiography / Q000379:methods; D008875:Middle Aged; D008954:Models, Biological; D033081:Shear Strength; D014057:Tomography, X-Ray Computed / Q000379:methods