Journal of the Mechanical Behavior of Biomedical Materials最新文献

{"title":"ZnO nanoparticles infused PVA-hyaluronic acid based hydrogel: An alternative solution for skin wound","authors":"Nafia Jawaid Kurd ,&nbsp;Eraj Humayun Mirza ,&nbsp;Tooba Khan ,&nbsp;Muhammad Atiq ur Rehman ,&nbsp;Muhammad Rizwan ,&nbsp;Aftab Ahmed Khan ,&nbsp;Abdulaziz Abdullah Alkhureif ,&nbsp;Pekka K. Vallittu","doi":"10.1016/j.jmbbm.2025.107324","DOIUrl":"10.1016/j.jmbbm.2025.107324","url":null,"abstract":"<div><div>This laboratory study aimed to synthesize and characterize various formulations of polyvinyl alcohol (PVA)-based hydrogels by incorporating 1.0 and 3.0 wt% of hyaluronic acid (HA) and zinc oxide (ZnO) nanoparticles (NPs) for skin wound healing. Six distinct PVA-HA based hydrogel formulations were developed with varying concentrations of ZnO (1 wt% and 3 wt%) using a freeze-thaw method comprising four cycles at −22 °C. The formulations were characterized through Fourier Transform Infrared Spectroscopy (FTIR), degradation analysis, moisture content analysis, pH sensitivity analysis, tensile strength testing, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and cell behavior assessment. Data were analyzed using one-way and two-way analysis of variance with a significance threshold set at 0.05. FTIR spectra confirmed functional groups that enhance the biocompatibility, mechanical stability, and hydrophobicity of the hydrogels. Among all the formulations, PVA-HA-ZnO 1 % demonstrated adequate durability and responsiveness to different pH conditions. The experimental hydrogels exhibited swelling in acidic environments, while shrinkage was observed in basic medium. A <em>p-value</em> of 0.005 in pH 6.5 vs 7.5 and a <em>p-value</em> of 0.0006 in pH 6.7 vs 8.1 was calculated. A significant difference in degradation characteristics was evident when HA was added to PVA (<em>p-value</em> of 0.04) and also when pure PVA was compared with samples containing both the ZnO and HA in conjugate (<em>p-value</em> of 0.03 for PVA vs PVA-HA-Zn01 % and <em>p-value</em> of 0.04 for PVA vs PVA-HA-ZnO3 %). Thermal stability testing indicated that increasing the concentration of ZnO NPs enhanced the thermal stability of the hydrogels, while the pure PVA formulation underperformed in thermal analysis. Additionally, the hydrogels facilitated adequate cell attachment; however, a higher concentration of ZnO NPs led to reduced cell attachment, indicating the cytotoxic behavior of ZnO. The hydrogel incorporating HA and 1 % ZnO demonstrated significant potential as a candidate for wound care applications, indicating the need for further investigation into its <em>in vivo</em> behavior and antimicrobial properties.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"175 ","pages":"Article 107324"},"PeriodicalIF":3.5,"publicationDate":"2025-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145879906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hair anisotropy and damage: Understanding hair cracking and fracture via the moving loop test","authors":"Daniel Samoylenko ,&nbsp;Leah Su Whelan ,&nbsp;Ailsa Yale ,&nbsp;Guillaume Marty ,&nbsp;Roberto Santoprete ,&nbsp;Luca Polacchi ,&nbsp;David Taylor","doi":"10.1016/j.jmbbm.2025.107320","DOIUrl":"10.1016/j.jmbbm.2025.107320","url":null,"abstract":"<div><div>Hair can become damaged and break as a result of mechanical actions such as brushing. Individual hairs (known as hair fibres) are usually tested to failure in tension but this does not reflect the type of loading to which they are normally subjected. Previously, we proposed a new test – the Moving Loop fatigue test – which simulates the extreme bending of tangled hair during repeated brushing. Previous results showed that this test is capable of generating longitudinal splits, simulating the phenomenon of split ends. In the present paper we report further results from this test method, expanding the number of hair types investigated and demonstrating the dependence on applied force and effects of environmental treatments (combinations of hydration and heating). In addition to recording the number of cycles to failure we also used interrupted testing to investigate the mechanisms of damage initiation and propagation. We found that cracks can initiate in one of three interfaces – cuticle/cuticle, cuticle/cortex and cortex/cortex. The first two result in splits which start at or near the hair surface and propagate across the hair fibre to cause fracture, whilst the cortex/cortex-initiated splits propagate along the hair to macroscopic lengths. We attribute these differences in behaviour to differing anisotropy of hair strength, due to varying bond strengths in the cell-membrane complexes in these three interfaces. Computer simulation using finite element analysis provided insights into the distribution of tensile and shear stress and the effects of anisotropy on failure modes.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"175 ","pages":"Article 107320"},"PeriodicalIF":3.5,"publicationDate":"2025-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145835766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aortic smooth muscle cells keep their spindle-shaped morphotype in low density collagen hydrogels","authors":"Chloé Techens ,&nbsp;Amira Ben Hassine ,&nbsp;Edwin-Joffrey Courtial ,&nbsp;David Eglin ,&nbsp;Stéphane Avril","doi":"10.1016/j.jmbbm.2025.107323","DOIUrl":"10.1016/j.jmbbm.2025.107323","url":null,"abstract":"<div><div>Smooth muscle cells (SMCs) of elastic arteries are essential to maintain mechanical homeostasis in the media layer. However, investigating the SMCs mechanoregulation mechanisms important to understand homeostasis and diseases progression, is hampered by a lack of <em>in vitro</em> model replicating realistic biological conditions. Indeed, previous studies have mainly been performed on 2D surfaces rather than in a 3D environment replicating more closely the tissue mechanics and composition. Thus, the objective of this study was to optimize a collagen hydrogel embedding SMCs 3D culture model where the “contractile” phenotype expressed by SMCs in healthy aortas, assessed by a spindle-shaped morphotype will be reproduced and conserved. A Design of Experiment (DoE) was established where 12 chemically different hydrogels were tested varying pH and collagen concentrations (7.4/7.7/8, 2.5/5.0/7.5/10.0 mg/mL) with 3 cell densities (50 000/100 000/150 000 cells/mL). SMCs contractile morphotype was optimal for low-collagen concentration hydrogels seeded at SMCs density of 100 000 cells/mL, independently of the hydrogel pH. The study provided an overview of the adaptation of the SMC population to the matrix shear modulus and viscosity, and provide a parameterized 3D model to study mechanoregulation of SMCs.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"175 ","pages":"Article 107323"},"PeriodicalIF":3.5,"publicationDate":"2025-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145835746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural finite element analysis of the lumbar spine applied to the conceptual design of a compliant interbody cage implant","authors":"Gabriele Cortis ,&nbsp;Alessandro Agostinelli ,&nbsp;Luca Cortese","doi":"10.1016/j.jmbbm.2025.107314","DOIUrl":"10.1016/j.jmbbm.2025.107314","url":null,"abstract":"<div><div>A detailed solid model of an entire lumbar segment is reconstructed through a reverse engineering approach based on a real patient Computed Tomography DICOM scan. The main structurally and functionally relevant elements have been considered in the model, including the L1-S1 vertebrae, intervertebral discs, ligaments, and the simplified structural and bracing effects of the principal lumbar muscles. Using the model, a structural Finite Element (FE) analysis is setup to provide an insight of stresses and range of motion of the “spinal mechanical system” under typical everyday as well as accidental loads. Organic bone, discs, ligaments physical and structural material data have been retrieved, and both static and fatigue load cases have been taken into account, collecting real world data from a review of literature works and of information available from accessible databases. A validation of the FE model is provided based on the so called Yamamoto protocol first, and then using experimental measurements performed on real patients, again taken from literature works. The numerical model proved to be accurate in the description of the stress states of the different parts of the spine and in reproducing the overall range of motion of the lumbar segment. A tentative design modification of rigid interbody cages and vertebral fixation systems used in present spinal fusion neurosurgery is then proposed, aimed at providing a certain level of compliance to the implant. This should restore a limited range of motion of the two adjacent vertebrae hosting the implant itself, reducing the possibility of subsequent adjacent segments diseases. The new cage and fixation system have been integrated in the FE model to replace a prospective “damaged” L4-L5 disc. The results of the numerical simulation demonstrated that the implant can withstand static and fatigue everyday life loads, as well as accidental overloads without failing. Additionally, the analysis showed that a limited mobility is maintained between the fused vertebrae.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"175 ","pages":"Article 107314"},"PeriodicalIF":3.5,"publicationDate":"2025-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of plate working length on fatigue life in load bearing osteosynthesis constructs: Experimental insights and validated finite element predictions","authors":"Dominic Mischler ,&nbsp;Mark Glyde ,&nbsp;Michael Kowaleski ,&nbsp;Antoine Vautrin ,&nbsp;Simon Lambert ,&nbsp;Peter Varga","doi":"10.1016/j.jmbbm.2025.107322","DOIUrl":"10.1016/j.jmbbm.2025.107322","url":null,"abstract":"<div><h3>Background</h3><div>Fatigue failure of osteosynthesis plates in load bearing constructs remains a significant clinical challenge, with plate working length (PWL) influencing stress distribution and implant life span. Despite conflicting evidence on PWL's impact, finite element (FE) models offer potential for predicting fatigue life, yet their application to PWL-specific fatigue in bone-plate constructs is limited.</div></div><div><h3>Methods</h3><div>This study investigated the effect of PWL on fatigue life in load bearing constructs using experimental cyclic testing and FE modeling. Synthetic bone models with a 10 mm osteotomy gap were stabilized with 3.5 mm stainless steel locking compression plates, testing short (1 empty hole), medium (3 empty holes), and long (5 empty holes) PWL configurations (N = 6 per group) under sinusoidal loading (260 N peak, 3 Hz). A second sub-study assessed the medium PWL across nine load levels (220–380 N). FE models, validated against experimental force-displacement curves, predicted cycles to failure using Basquin's stress-based criteria. Statistical analyses compared experimental and FE-predicted cycles.</div></div><div><h3>Results</h3><div>Shorter PWL significantly increased fatigue life (short: 1.19 × 10⁶ ± 0.28 × 10⁶ cycles; medium: 0.35 × 10⁶ ± 0.07 × 10⁶; long: 0.20 × 10⁶ ± 0.04 × 10⁶; p &lt; 0.003). FE predictions closely matched experimental cycles for medium and long PWL (p &gt; 0.05) but underpredicted for short PWL (p = 0.03), likely due to tied interface assumptions. Most short PWL constructs survived beyond 10⁶ cycles, reaching up to 1.5 million cycles in the very high-cycle fatigue regime without failing, where Basquin's accuracy may decrease. Sub-study 2 showed a strong load-life correlation (R² = 0.96), with FE predictions achieving high accuracy (CCC = 0.972, REE = 6.3 %).</div></div><div><h3>Conclusion</h3><div>Shorter PWL enhances fatigue life in load bearing constructs by reducing plate stress, challenging traditional beliefs favoring longer PWL. FE models effectively predict fatigue life for medium and long PWL, supporting preoperative optimization, but require refinement for short PWL, including frictional contact modeling and alternative fatigue models for very high-cycle fatigue. Validation in physiological conditions is needed to enhance clinical applicability.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"175 ","pages":"Article 107322"},"PeriodicalIF":3.5,"publicationDate":"2025-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145835706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cervical spine posture, but not head-end motion constraints, governs the kinematic and kinetic response in sub-injurious axial impacts","authors":"Darcy W. Thompson-Bagshaw PhD ,&nbsp;Ryan D. Quarrington PhD ,&nbsp;Peter A. Cripton PhD ,&nbsp;Claire F. Jones PhD","doi":"10.1016/j.jmbbm.2025.107321","DOIUrl":"10.1016/j.jmbbm.2025.107321","url":null,"abstract":"<div><div>Head-first impacts can produce traumatic cervical spine injuries resulting in tetraplegia. These injury patterns are thought to relate to the alignment of the loading vector relative to the spinal column. Pre-impact posture and subsequent head and intervertebral kinematics, including spinal buckling and head motion relative to the spine and torso, can generate complex spinal configurations. These motions often precede injury onset and can be observed with <em>ex vivo</em> models in which applied loads remain below injury thresholds. This study examined the kinematic response of the cervical spine to dynamic axial compression at sub-injurious severities, enabling inter- and intra-specimen comparisons across varying initial spinal postures and head motion constraints. Human cervical spine specimens (N = 7) were subjected to repeated 1 m/s axial impacts, while the applied head constraint (sagittal rotation and/or anterior translation) and initial posture (anterior eccentricity and curvature) were varied. Pre-impact head–T1 eccentricity and curvature, head-end motion during impact, intervertebral kinematics, and impact loads were recorded. Head-end anterior translation and flexion rotation were minimal across all constraint conditions (&lt;11.5 mm, &lt;9.0°). Head constraint had no detected effect on peak force (541–2457 N), deformation (3.2–11 mm), or stiffness (81–1074 N/mm) (all p &gt; 0.05). In contrast, greater initial curvature and eccentricity reduced stiffness and peak force, and increased deformation (p &lt; 0.05). Greater initial curvature also produced larger changes in intervertebral flexion-extension during impact (p &lt; 0.05). These results demonstrate that pre-impact posture dictates the cervical spine's sub-injurious axial response at discrete anterior eccentricities, which may be further explored using computational models validated using this dataset.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"175 ","pages":"Article 107321"},"PeriodicalIF":3.5,"publicationDate":"2025-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145835786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of posterior inclination and facet joint orientation on the annulus fibrosus stiffness and rotational stability of the thoracolumbar spine","authors":"Federica Incatasciato ,&nbsp;Peter P.G. Lafranca ,&nbsp;Luuk H.F. Souren ,&nbsp;Tijl A. van der Velden ,&nbsp;René M. Castelein ,&nbsp;Tom P.C. Schlösser ,&nbsp;Bert van Rietbergen ,&nbsp;Keita Ito ,&nbsp;Joeri Kok","doi":"10.1016/j.jmbbm.2025.107319","DOIUrl":"10.1016/j.jmbbm.2025.107319","url":null,"abstract":"<div><div>The etiology of adolescent idiopathic scoliosis (AIS) remains unresolved. The human upright posture results in vertebral posterior inclination. It has been hypothesized that this can lead to increased posterior shear in the thoracolumbar spine depending on the actual inclination angle and facet joint orientation which in turn could lead to unlocking of facet joints. This would result in increased axial rotation and thereby the likelihood of overstraining the fibers of the anterior annulus fibrosus (AF). Potentially, these aspects may enhance the risk of AIS development and progression. In this population-based in silico study, we use novel computational techniques to examine how posterior vertebral inclination and facet joint orientation affect range of motion and AF fiber strain in a cohort of children with increased AIS risk. Finite element subject-specific models of the T11-T12 motion segment were created from MR images of 18 prepubescent girls. An axial compressive force representing the combined action of gravity and muscle forces together with axial rotation moment was applied at three posterior inclination angles (5°, 15°, 25°). Facet joint orientation was modelled as subject-specific, lumbar, or thoracic. Posterior inclination had little impact on the stiffness of the neutral zone. However, the fraction of fibers exceeding 15 % strain increased from 14.5 ± 9.3 % at 5° to 18.7 ± 12.4 % at 25°. Transverse facet joint orientation angle highly correlated with the range of motion, but poorly correlated with fiber overstraining. Comparing the lumbar-oriented to the thoracic-oriented facet joints, fiber overstraining increased across all inclination degrees. This study showed that posterior inclination and increasing thoracic-like facet joint orientation increases AF fiber strains, providing further biomechanical evidence that helps understanding AIS development.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"175 ","pages":"Article 107319"},"PeriodicalIF":3.5,"publicationDate":"2025-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145829440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of a novel 4-day decellularisation protocol for porcine flexor tendons: A comparative study with a 26-day process","authors":"Victoria Haines ,&nbsp;Jennifer Helen Edwards ,&nbsp;Anthony Herbert","doi":"10.1016/j.jmbbm.2025.107318","DOIUrl":"10.1016/j.jmbbm.2025.107318","url":null,"abstract":"<div><div>Rupture of the anterior cruciate ligament is a common sports-related injury that lacks intrinsic healing capacity, often necessitating surgical intervention. Our group has developed a new graft biomaterial, the decellularised porcine super flexor tendon (pSFT), designed to mitigate immune rejection post-implantation by removing cellular components. The current 26-day decellularisation process attenuates the mechanical properties of the graft, potentially disrupting the structural micro-cues that influence cell repopulation and integration. This study investigates a shortened 4-day protocol to determine whether mechanical properties are preserved more closely to native, unprocessed tissue.</div><div>Histological analysis and DNA quantification confirmed effective cell removal for both the 26-day and 4-day protocols. Native, 26-day processed, and 4-day processed grafts were mechanically evaluated through stress relaxation and failure testing. Following stress relaxation testing, several Maxwell-Weichert viscoelastic parameters were found to significantly differ between 26-day and native groups (E₀, E₁, E₂ &amp; τ₂), whereas between 4-day and native groups fewer significant differences were found (E₁ &amp; E₂). Following failure testing, again several parameters were found to significantly differ between 26-day and native groups (P_FAIL, UTS, E_linear and ε_T), whereas between 4-day and native groups only one parameter was significantly different (E_linear).</div><div>These findings indicate that the 4-day decellularisation process better preserves the native tissue mechanical properties, potentially reducing structural alterations and improving suitability for anterior cruciate ligament replacement.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"175 ","pages":"Article 107318"},"PeriodicalIF":3.5,"publicationDate":"2025-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Time-resolved prediction of dental implant biomechanics through integration of finite element analysis, osseointegration dynamics, and deep learning","authors":"Jesús Rodriguez-Molinero ,&nbsp;María Prados-Privado","doi":"10.1016/j.jmbbm.2025.107316","DOIUrl":"10.1016/j.jmbbm.2025.107316","url":null,"abstract":"<div><h3>Background</h3><div>Dental implant longevity depends on the complex interaction between mechanical stability and biological osseointegration. While finite element analysis (FEA) provides valuable mechanical insight, it remains static and computationally expensive.</div></div><div><h3>Objective</h3><div>This study presents a hybrid time-resolved computational framework combining finite element data, osseointegration dynamics, and deep learning to predict the biomechanical behavior of titanium dental implants throughout the healing process.</div></div><div><h3>Methods</h3><div>A parametric 3D FEA model simulated 800 implant–bone configurations varying in geometry, loading, and bone quality. A mechanobiological model of osseointegration described the monthly evolution of bone density, bone–implant contact (BIC), and interfacial stiffness over 12 months. These temporal variables were integrated into a hybrid Multilayer Perceptron – Long Short-Term Memory (MLP–LSTM) neural network — designed to capture both spatial and time-dependent features—trained to predict von Mises stress (<span><math><mrow><msub><mi>σ</mi><mrow><mi>V</mi><mi>M</mi></mrow></msub></mrow></math></span>), maximum displacement (<span><math><mrow><msub><mi>δ</mi><mi>max</mi></msub></mrow></math></span>), and fatigue safety factor (FSF, an indicator of long-term structural failure risk).</div></div><div><h3>Results</h3><div>The model achieved R² &gt; 0.98 for all outputs and mean absolute errors &lt;0.015. Temporal simulation revealed that interfacial stiffness increased by 270 %, while FSF declined nonlinearly with load above 200 N. Predictions were generated in &lt;0.01 s per case, offering &gt;4000 × speed-up compared to conventional FEA.</div></div><div><h3>Conclusions</h3><div>The framework captures both mechanical and biological evolution of the implant–bone interface, providing physiologically realistic, computationally efficient predictions. This approach represents a step toward personalized, AI-assisted implant design and load management. Clinically, this tool allows for rapid pre-surgical screening of implant designs against patient-specific risk factors. Limitations include the reliance on synthetic data derived from simplified bone geometries, static loading assumptions, and unvalidated mechanobiological parameters, necessitating future in vivo validation. These findings represent a computational proof-of-concept and require validation against patient-specific geometries and biological data before clinical adoption.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"175 ","pages":"Article 107316"},"PeriodicalIF":3.5,"publicationDate":"2025-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145784198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Benchmarking PA12 and PA12CF35 for selective laser sintering of patient-specific implants: a thermo-mechanical analysis","authors":"K. Zouggar ,&nbsp;D. Guerraiche ,&nbsp;K. Guerraiche ,&nbsp;K. Bendine ,&nbsp;M.W. Harmel ,&nbsp;K. Madani ,&nbsp;R.D.S.G. Campilho","doi":"10.1016/j.jmbbm.2025.107311","DOIUrl":"10.1016/j.jmbbm.2025.107311","url":null,"abstract":"<div><div>The present research investigates the impact of carbon-filler reinforcement on the thermo-mechanical characteristics of polyamide 12 (PA12) during Selective Laser Sintering (SLS) for the production of specific cranial implants. A complete thermo-mechanical finite element analysis was developed using user subroutines (DFLUX, UMAT, and UEPActivationVol) from a commercial software Abaqus for modeling variations of temperature, warpage, crystallization kinetics, shrinkage, and residual stresses accumulation during the complete layer-wise sintering fabrication process. The model underwent quantitative validation against experimental benchmarks, demonstrating dimensional deviations of less than 5 % and warpage prediction errors below 15 %, thereby affirming its predictive reliability. The validated framework was subsequently utilized to compare neat PA12 with a 35 % carbon filler-reinforced composite (PA12CF35). The research results suggest that PA12CF35 displays a 26 % improvement in solidification speed, a 17.5 % decrease in shrinkage, and an estimated 5 % enhancement in warpage resistance compared to PA12. The use of carbon fillers improves thermal conductivity and reduces the peak temperature by 3.4 %, allowing more uniform melting and cooling across consecutive layers. Additionally, PA12CF35 exhibits a 7.7 % decrease in residual stress, resulting in improved structural stiffness and dimensional stability post-solidification.</div><div>The assessed results reveal that the designed model approach efficiently guides process optimization and composite design in polymer-based SLS. The enhanced thermo-mechanical properties of PA12CF35 underscore its suitability for advanced cranial implants developed via additive manufacturing.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"175 ","pages":"Article 107311"},"PeriodicalIF":3.5,"publicationDate":"2025-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145795540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}