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Item type:Publication, Access status: with files , Tibiotarsal mechanical behaviour is mainly a function of bone structure and not mineral density in female adolescent chickens(Frontiers Media S.A., 2026-09-28); ; 10 5 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Gradient orientation governs mechanical and regenerative outcomes in functionally graded bone scaffolds: a coupled finite element–agent-based modelling studyCritical-sized bone defects remain a major clinical challenge, requiring scaffolds that combine mechanical stability with regenerative capacity. Functionally graded scaffolds offer a promising strategy by spatially varying porosity to optimise load transfer and tissue ingrowth. Here, we apply an established coupled poroelastic finite element–agent-based modelling (FEA–ABM) framework as a comparative platform to evaluate six cylindrical scaffold configurations modelled using Ti–6Al–4V material properties: two opposing axial-gradient designs, two opposing radial-gradient designs, and their corresponding uniform controls under physiologically representative loading. Poroelastic finite element analysis was used to compute local shear strain and fluid velocity, which regulated progenitor differentiation, proliferation, apoptosis, and migration in the agent-based model. Simulations representing 150 days of healing showed that axial gradients with larger pores at the host bone interface produced the greatest bone ingrowth, reaching approximately 77% pore occupancy compared with 69% in the uniform axial scaffold and 60% in the opposite axial gradient. In contrast, radial gradients did not substantially alter overall bone regeneration compared with the uniform radial scaffold, but the design with denser peripheral struts markedly improved mechanical performance, reducing volume-weighted P99 von Mises stress to approximately 41 MPa compared with about 57-71 MPa in the radial uniform and opposite radial-gradient designs. These findings reveal a design trade-off between regenerative capacity and structural competence, suggesting that gradient orientation should be selected according to the mechanical and biological requirements of the target defect environment. By applying the FEA–ABM framework consistently across the investigated configurations, this study provides comparative evidence to inform the selection of pore-size-gradient designs according to the regenerative and mechanical requirements of the target defect.Publicationtype: Journal Article5 3 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Evaluation of angiogenic potential of silk fibroin fleece and membrane scaffolds using a co-culture system of huvecs and dpscs in fibrin gel(Elsevier, 2026-09-10); ; ; Gosau, MartinPublicationtype: Journal Article6 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Distal cortical notching significantly decreases tibial stability following tibial tubercle osteotomy: an in vitro porcine biomechanical study(Wiley, 2026-07-17); ; ; ; Purpose: Distalizing tibial tubercle osteotomy (dTTO) is an effective treatment for patella alta, yet complications can be severe. This study evaluates the biomechanical effects of distal cut orientation on tibial fracture risk. It was hypothesised that orthogonal cutting and cortical notching reduce tibial stability. Methods: A total of 61 porcine tibiae were tested in three setups. Four distal cut orientations were compared in a load-to-failure analysis (n = 32): oblique (Obl), orthogonal without notch (Orth), orthogonal 2-mm notch (Orth2), orthogonal 4-mm notch (Orth4) (each n = 8). Cyclic loading was evaluated in Obl, Orth and Orth2 (n = 17), followed by comparison of plate versus (2-hole one-third tubular plate) 3.5-mm screw fixation in Orth2 specimens (n = 12). Specimens were embedded in PMMA and axially loaded (MTS Bionix 358). Load-to-failure, stiffness and cycles until failure were recorded. Residual tibial thickness was measured. Linear regression analysed the relationship between residual thickness and failure load. Statistical analysis included t-tests and ANOVA (α = 0.05). Results: Obl showed the highest failure load (784.5 N ± 118.3), although the difference compared to Orth (538.8 N ± 229.5, p = 0.087) did not reach statistical significance. Notching significantly reduced load-to-failure (2-mm: 294.0 N ± 91.8; 4 mm: 274.6 N ± 96.5). In cyclic testing, Obl withstood most cycles until failure (5894 ± 2187) compared to Orth (3142 ± 808; p = 0.004), while Orth2 failed sooner (1400 ± 530, all p < 0.005). Osteosynthesis techniques did not affect failure load (p = 0.802). Stiffness and residual tibial thickness were comparable. Distal tibial thickness was associated with failure load in all groups (all p < 0.05). Conclusion: In this porcine model, cortical notching significantly reduced tibial stability and should be avoided during TTO. Oblique distal cuts demonstrated greater resistance to cyclic loading, while no significant difference was observed in static load-to-failure. Osteosynthesis technique did not affect load-to-failure. Level of Evidence: NA, cadaveric biomechanical study.Publicationtype: Journal Article25 6 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Sost deficiency leads to greater bone vascular porosity, but similar osteocyte lacunar properties with increasing age(Elsevier, 2026-07-06); ; ; Sclerostin neutralizing antibody is an approved anabolic drug used to increase bone mass. Numerous preclinical studies examined bone mass and microstructural changes in mice receiving sclerostin neutralizing antibodies or mice lacking sclerostin, such as Sost knock out mice. Surprisingly no preclinical studies examined the effect of sclerostin deficiency with aging, despite the treatment being used primarily in older individuals. Thus, our primary aim was to examine the effect of long-term Sost deficiency on bone microstructure, including osteocyte lacunar and bone vascular porosity properties across ages. Our results show that Sost deletion led to sustained bone formation across the mouse's lifespan, whereas wild-type control mice experienced bone maturation followed by age-related declines in bone volume. Lacunar parameters were also affected due to Sost deletion, with altered lacunar density and volume in young mice, but these differences were not present in old mice. Our secondary aim was to examine the effect of short-term sclerostin deficiency on bone microporosity in woven and cortical bone after an osteotomy in adult female C57BL6J mice. Short term sclerostin antibody treatment did not alter vascular or lacunar porosity within lamellar or newly formed woven bone, suggesting that timing and duration are critical for therapeutic efficacy. In summary, Sost KO mice exhibit sustained cortical thickening and pronounced bone vascular porosity, particularly as the mice aged. As sclerostin neutralizing antibody becomes more widely used in an aging population, for extended periods of time, this work helps us understand the effects of long-term inhibition.Publicationtype: Journal Article9 5 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Primary fixation stability evaluation of pre-bent titanium miniplate configurations in mandibular reconstruction(Frontiers Media S.A., 2026-02-12); ; ; ; Mandibular reconstruction is a commonly performed procedure in maxillofacial surgery with many different possible reconstructive strategies. Generally, modular fixation with miniplates has the advantage of an easier plate removal, mostly possible through an intraoral access. For patient-specific plates, the combination of reconstruction plates in the posterior area with anterior miniplates has been described as biomechanically and clinically beneficial. To our knowledge, conventional miniplates have not been biomechanically assessed in combination with reconstruction plates. Therefore, the present study aimed to evaluate combinations of pre-bent anterior miniplates with a posterior pre-bent reconstruction plate in silico as an alternative to pre-bent fixation strategies including only miniplates. The results indicate, that from a biomechanical perspective, the combination of a posterior pre-bent short reconstruction plate with anterior pre-bent miniplates is a viable alternative to fixation strategies including solely pre-bent miniplates. The process of pre-bending did not affect intersegmental strains. Analogously to patient-specific plates, the combination of a posterior pre-bent reconstruction plate with pre-bent anterior miniplates seems a surgically and biomechanically promising alternative to fixation strategies with pre-bent miniplates alone.Publicationtype: Journal Article12 13 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Biomechanical evaluation of shape-optimized CAD/CAM magnesium plates for mandibular reconstruction(Elsevier, 2026-01); ; ; ; Magnesium CAD/CAM miniplates are a promising alternative to titanium plates for mandibular reconstruction. However, gas formation is an inherent part of the magnesium degradation process, and thus, the quantity of magnesium used in fixation scenarios should be limited. Previous studies described several strategies to limit material volume, such as plate thickness reduction and shape-optimization. In particular, shape-optimization has been described as a strategy to limit material volume while maintaining mechanical integrity. In consequence, the present study compared a shape-optimized CAD/CAM magnesium miniplate with standard CAD/CAM magnesium miniplates of varying thicknesses using a biomechanical finite element model. A single-segment mandibular reconstruction was chosen as the investigative scenario, evaluated under different biting tasks to assess the different plate shapes. The shape-optimized magnesium plate demonstrated similar primary fixation stability compared to standard CAD/CAM magnesium miniplates, despite having reduced plate material and surface area. Shape optimization could help minimize magnesium volume and surface area to mitigate the issue of gas formation during the degradation process in vivo while maintaining biomechanical performance comparable to common CAD/CAM miniplates.Publicationtype: Journal Article18 24 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Prospective functional assessment after mandible reconstruction and bone healing assessmentObjectives: Mandibular reconstruction remains a clinical challenge due to a high rate of osseous non-unions. Mechanical factors are known to influence the bone regeneration process. Therefore, bite force levels, both immediately after surgery and during the bone healing process, are believed to play a critical role in the healing outcome. The aim of this study was to evaluate bite force and mandibular mobility measurements over time following mandibular reconstruction and to relate these measurements to the bone healing outcome. Materials and methods: In this prospective study, 28 patients were included and underwent functional measurements pre-operatively and at two weeks, four weeks, eight weeks, three months, and six months post-reconstruction. Additionally, the healing outcome was assessed using post-operative imaging. Results: After surgery, the functional parameters - including bite force, mouth opening, protrusion, and laterotrusion - significantly decreased. However, between the initial post-operative measurement and the final follow-up six months after surgery, all parameters showed a significant increase. Two weeks post-operatively, only 9 of the 28 patients were able to participate in the bite force measurement. However, 6 of these patients exhibited incomplete osseous union, which was associated with a mean bite force of 166 N at two weeks (mean over the whole cohort after six months of 154 N). Conclusions: This study demonstrated the trends in functional measurements over time following mandibular reconstruction and identified a significant trend in association between excessive post-operative bite force and incomplete osseous union. Clinical relevance: In consequence, clinical strategies to reduce mechanical over-stimulation could be evaluated in future studies, such as soft food intake for 3 months after mandibular reconstruction.Publicationtype: Journal Article16 20 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Impact of osteotomy angle on bone failure risk in a modified pull-through approach: a finite element analysis(BioMed Central, 2025-12-01); ; ; ; Background: A modified pull-through approach represents a promising treatment strategy to access tumors in the posterior oral cavity. The design of the wedge osteotomy plays a key role in preserving postoperative mechanical stability while enabling surgical access. However, the optimal osteotomy design to reduce fracture risk remains unclear. Therefore, this study aimed to test osteotomy wedge designs that have the potential to lower the bone fracture risk. Methods: Four wedge osteotomy configurations were compared using finite element analysis based on a realistic mandible model. Each design differed in the angles and curvature of the osteotomy planes. Unilateral molar clenching was simulated, and mechanical strains were quantified and compared to the yield strain of cortical bone in the canine region to evaluate the risk of bone failure. Results: The finite element analysis showed that a wedge osteotomy with less acute angles in the canine region has a lower fracture risk when compared to osteotomies with sharp angles. Peak bone strain values could be reduced by half by changing the osteotomy angle at the canine region. Conclusions: A larger angle between the osteotomy cutting planes offers mechanical advantages by reducing strain concentrations in critical regions. These findings provide valuable guidance for refining the current surgical technique and support the integration of biomechanical analyses into osteotomy planning to optimize surgical outcomes.Publicationtype: Journal Article20 21 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Parametrized statistical appearance and shape modelling strategy to predict proximal and diaphyseal femoral fracturesIntroduction: Femoral loading leading to a fracture is known to vary with anthropometry, and patient-specific finite element models have provided important insights into fracture prediction but are often very time consuming to generate. Additionally, existing parametric models do not simultaneously account for variations in both femur geometry and bone density distribution and remain limited to either the femoral shaft or the proximal femur. This inhibits their ability to predict fractures involving both the shaft and proximal regions. Methods: In the present study, a novel parametric femur modeling strategy was developed to create whole femur models based on stature, BMI, and age input, including density distribution and geometrical variations, for fracture loading predictions. A statistical shape and appearance femur model was developed based on an input set of CT scans of healthy female femurs (N = 18) between the ages of 50 and 70. Thereafter, multilinear regressions were used to relate principal components to the subject anthropometric characteristics and develop parametric models. The developed parametric models were evaluated using traditional patient-specific models for their potential to represent the influence of changing patient stature, BMI, and age on femoral fractures. Femoral fracture load in three-point bending, axial torsion, and lateral fall cases was predicted using the parametric as well as subject-specific femur models. Results: The developed parametric model was able to predict femoral fracture load variations due to changing anthropometry and age with an average difference of 4.85% compared with predictions using subject-specific models. Discussion: Therefore, this novel parametric femur model can predict fracture loading while directly incorporating the influence of changing patient anthropometry. In the future, the model could support the development of orthopedic devices tailored to specific patient anthropometries to help mitigate femoral fractures.Publicationtype: Journal Article14 14