Although mechanical stress is known as being a significant factor in bone remodeling, most implants are still made using materials that have a higher elastic stiffness than that of bones.Load transfer between the implant and the surrounding bones is much detrimental, and osteoporosis is often a consequence of such mechanical mismatch. The concept of mechanical biocompatibility has now been considered for more than a decade. However, it is limited by the choice of materials, mainly Ti-based alloys whose elastic properties are still too far from cortical bone. We have suggested using a bulk material in relation with the development of a new beta titanium-based alloy. Titanium is a much suitable biocompatible metal, and betatitanium alloys such as metastable TiNb exhibit a very low apparent elastic modulus related to the presence of an orthorhombic martensite. The purpose of the present work has been to investigate the interaction that occurs between the dental implants and the cortical bone. 3D finite element models have been adopted to analyze the behaviour of the bone-implant system depending on the elastic properties of the implant, different types of implant geometry, friction force, and loading condition. The geometry of the bone has been adopted from a mandibular incisor and the surrounding bone. Occlusal static forces have been applied to the implants, and their effects on the bone-metal implant interface region have been assessed and 2 compared with a cortical bone/ bone implant configuration. This work has shown that the low modulus implant induces a stress distribution closer to the actual physiological phenomenon, together with a better stress jump along the bone implant interface, regardless of the implant design.Keywords: Dental biomechanics, Beta titanium alloy, Low modulus implant, Numerical modelling, Bone-implant interface
IntroductionOver the last few decades, considerable progress in dental implantology has been made, with success rates exceeding 95% [1]. Implant stability is commonly considered as playing a major role in a successful osseointegration. Obtaining post-operative osseointegration is necessary in order to establish a solid and durable connection between the implant and the osseous structure. In agreement with the Wolff law, a process of osseous remodelling adapted to the stress level occurs after implantation [2][3][4]. This process is controlled by mechanical loads.When the occlusal forces induced on the bone exceed a physiological level, bone resorption can occur, with possible failure [5]. More importantly, the long-term performance of an implant is known to be strongly dependent on the bone tissue interaction [6]. The strain state which takes place at the interface between the bone and implant controls the bone tissue remodelling mechanisms [7]. Bone resorption is associated with a low strain state, and bone necrosis occurs when strain exceeds the maximum level.Evaluation of the risk requires a comprehension of the load transfer along the bone-dental implant interface. T...