Modeling of the human mandibular periosteum material properties and comparison with the calvarial periosteum

Knowledge of mandibular periosteum mechanical properties is fundamental for understanding its role in craniofacial growth, in trauma and bone regeneration. There is a lack in the literature regarding mechanical behavior of the human periosteum, including both experimental and modeling aspects.The proposed study involves tensile tests of periosteum samples from different locations including two locations of human mandibular periosteum: lingual and vestibular, compared with samples from various locations of the calvarial periosteum. We propose to analyze the tensile response of the mandibular periosteum using a model, initially applied on the skin, and based on a structural approach involving the mechanical properties of the corrugation of the collagen.Two different approaches for the model parameters’ identification are proposed: (1) identification from experimental curve fitting and (2) identification from histological study. This approach allows us to compare parameters extracted from the traction test fitting to structural parameters measured on periosteum histological slices. Concerning experimental aspects, we showed significant differences, in terms of stiffness, between calvarial and mandibular periostea. (The mean final stiffness is Ec,mand=18MPa for the mandible versus E_{c , calv}= 70.1 for the calvaria.) About modeling, we succeed to capture the correct mechanical behavior for the periosteum, and the statistical analysis showed that certain parameters from the geometric data and traction data are significantly comparable (e.g., p= 0.3 for E_c). However, we also observed a discrepancy between these two approaches for the elongation at which the fibril has become straight (p= 0.0001).