Use of micro-CT-based finite element analysis to accurately quantify peri-implant bone strains: a validation in rat tibiae

Abstract

Although research has been addressed at investigating the effect of specific loading regimes on bone response around the implant, a precise quantitative understanding of the local mechanical response close to the implant site is still lacking. This study was aimed at validating micro-CT-based finite element (µFE) models to assess tissue strains after implant placement in a rat tibia. Small implants were inserted at the medio-proximal site of 8 rat tibiae. The limbs were subjected to axial compression loading; strain close to the implant was measured by means of strain gauges. Specimen-specific µFE models were created and analyzed. For each specimen, 4 different models were created corresponding to different representations of the bone-implant interface: bone and implant were assumed fully osseointegrated (A); a low stiffness interface zone was assumed with thickness of 40 µm (B), 80 µm (C), and 160 µm (D). In all cases, measured and computational strains correlated highly (R 2 = 0.95, 0.92, 0.93, and 0.95 in A, B, C, and D, respectively). The averaged calculated strains were 1.69, 1.34, and 1.15 times higher than the measured strains for A, B, and C, respectively, and lower than the experimental strains for D (factor = 0.91). In conclusion, we demonstrated that specimen-specific FE analyses provide accurate estimates of peri-implant bone strains in the rat tibia loading model. Fur-

In vivoassessment of the effect of controlled high- and low-frequency mechanical loading on peri-implant bone healing

“…Instead they were used to validate established micro-finite element models, providing a three-dimensional quantification of the strain throughout the whole tibiae [19,20]. We estimated maximum tensile strains at 25 per cent of the tibia length (hence corresponding to the strain gauge position and alignment) of approximately 260 m strain for the implanted tibiae subjected to 10 N loading.…”

“…Bone strains measured on eight excised rat hindlimbs before and after implant placement [19,20] were used to establish the relationship between the applied load and the resulting bone strain. In short, a single element strain gauge (type FLG-02-11, TML, Tokyo Sokki Kenkyujo Co., Ltd) was glued onto the exposed lateral bone surfaces of the intact tibiae at 25 per cent of the tibia length.…”

Maximum principal strain as a criterion for prediction of orthodontic mini-implants failure in subject-specific finite element models

“…Recent studies of bone biomechanics found that bone failure by fracture was driven by deformation, and strain-based criteria can well predict fracture sites. [12][13][14] These findings may cause us to reconsider the use of stress-based criteria in evaluating the mechanical environment around implants and expose the need in the dental literature for validated stress and strain criteria for predicting OMI or dental implant failure in finite element (FE) models.…”

Stress Distribution in Single Dental Implant System

“…13,15,23 Finite element models obtained from micro-CT scanning have been widely used for the evaluation of biomechanical features of oral tissues and biomaterials. 15,24 The micro-CT scanning allows for voxel-based finite element models to reproduce with high fidelity the external geometry and the internal architecture of the bone tissue and biomaterials. 15 Regarding mathematical analysis by the FE method, any technique used for modeling has more reliability when the results are compared with experimental data.…”

“…[12][13][14] It is known for long that for biologic or artificial materials (such as implants) interfacing biologic tissues, the success is limited because of complex structure of biologic materials or the interface. 15 There, however, are few studies concerning the specific situation of the deformation around a single implant.…”