Force-displacement relationship in the extraction of a porcine tooth from its socket: Experiments and numerical simulations

Results of new investigations about the global tensile stiffness and strength of the periodontal ligament are presented. Experimental results are reported first, referring to the extraction of swine teeth from their sockets: force–displacement curves are shown, obtained from samples including a portion of the jaw and a canine swine tooth. Numerical simulations of the same tooth extraction tests are then presented, which exploit specific modelling techniques previously developed. In particular, use is made of an interface finite element capable to describe the fibrous structure of the periodontal ligament, and of a stress–stretch constitutive model, for a single collagen fibre, based on the multiscale nature of its subfibrillar microstructure. The comparison between the new experimental results and the numerical ones helps in understanding the soundness of the adopted mechanical models in the simulations. This study is expected to be mainly useful in providing results usable for the indirect validation of mechanical models of both the periodontal ligament and its basic constituent, the single collagen fibre.