Mechanical characterization of bovine periodontal ligament.
This study is part of a research program that aims to develop a constitutive three-dimensional model of the periodontal ligament (PDL) through the identification of pertinent material parameters. As part of this program, bovine PDL was utilized to establish stress-strain responses under tensile and compressive loading conditions. Fresh bovine molars were secured, frozen and prepared to appropriate dimensional specifications. Bar-shaped specimens that comprised portions of dentine, PDL and bone were produced. Push-pull tests were conducted using a specifically constructed loading machine. Full range monotonic stress-strain diagrams were generated. The effect of a rate increase on cyclic S-E diagrams was also determined. The influence of specimen thickness was expressed in terms of modulus of elasticity, strength, uniaxial maximizer strain, and strain energy density. The overall load-response was heavily hysteretic in compression. On the tensile side, after a steep rise, the curve tended to flatten out asymptotically. Variations in rate that spanned four orders of magnitude had no effect on reciprocal load responses. The E-modulus was in the 4-8 MPa range, the strength of the PDL was 1-2 MPa, the maximizer strain was at 45-60% and the strain energy density ranged between 0.3 and 0.4 MPa.
Laboratory of Applied Mechanics and Reliability Analysis, Swiss Federal Polytechnical School (EPFL), Lausanne, Switzerland.
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Pini
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Wiskott
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Scherrer
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Botsis
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Belser
D000539:Alveolar Process / Q000033:anatomy & histology / Q000502:physiology; D000704:Analysis of Variance; D000818:Animals; D001696:Biomechanical Phenomena; D002417:Cattle; D019245:Compressive Strength; D003799:Dental Stress Analysis / Q000295:instrumentation; D003804:Dentin / Q000033:anatomy & histology / Q000502:physiology; D004548:Elasticity; D008859:Microscopy, Polarization; D010513:Periodontal Ligament / Q000033:anatomy & histology / Q000502:physiology*; D013314:Stress, Mechanical; D013696:Temperature; D013718:Tensile Strength; D016474:Weight-Bearing