Finite element predictions compared to experimental results for the effective modulus of bone tissue engineering scaffolds fabricated by selective laser sintering

Cahill, Senan; Lohfeld, Stefan; McHugh, Peter E.

doi:10.1007/s10856-009-3693-5

Cited by 79 publications

(65 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…finite element models) for the simulation of the mechanical performance of laser sintered scaffolds. The idealised CAD models are inappropriate, as it has been shown in Cahill et al [46], as they do not take the roughness and microporosity into account. …”

Section: Resultsmentioning

confidence: 99%

Fabrication, mechanical and in vivo performance of polycaprolactone/tricalcium phosphate composite scaffolds

et al. 2012

View full text Add to dashboard Cite

In this paper, the use of the Selective Laser Sintering (SLS) process for the generation of bone tissue engineering scaffolds from PCL and PCL/TCP is explored. Different scaffold designs are generated and are assessed from the point of view of manufacturability, porosity and mechanical performance. Large scaffold specimens are generated, with a preferred design, and are assessed through an in vivo study in a critical size bone defect in the sheep tibia with subsequent microscopic, histological and mechanical evaluation. Further explorations are performed to generate scaffolds with increasing TCP contents.Scaffold fabrication from PCL and PCL/TCP mixtures with up to 50 mass-% TCP is shown to be possible. With increasing macroporosity the stiffness of the scaffolds is seen to drop, however, the stiffness can be increased by minor geometrical changes, such as the addition of a cage around the scaffold. In the animal study the selected scaffold for implantation did not perform as well as the TCP control in terms of new bone formation and the resulting mechanical performance of the defect area. A possible cause for this is presented.

show abstract

Section: Resultsmentioning

confidence: 99%

Fabrication, mechanical and in vivo performance of polycaprolactone/tricalcium phosphate composite scaffolds

et al. 2012

View full text Add to dashboard Cite

show abstract

“…By their nature, CAD models account for only the designed scaffold macroporosity and do not account for microporosity within the scaffold structure or surface roughness that are present due to the fabrication process. Cahill et al found that models based on the designed scaffold geometry over-predicted the scaffold stiffness by up to 147% and that surface roughness is a factor that needs to be accounted for 4 . High resolution finite element meshes have been successfully generated from micro-CT scans giving accurate models of the real geometries of both bone tissue engineering scaffolds 6,10,38,49,50,52,57 and native bone tissue 2,29,40,47,51 .…”

Section: Introductionmentioning

confidence: 99%

“…However, this type of scaffold material is inhomogeneous at the microscale level with the inclusion of micropores and β-TCP particles 33 . Previous studies have shown that simple 3D CAD geometries are insufficient to capture the mechanical behaviour of this type of SLS-fabricated scaffolds using finite element modelling 4,57 . By their nature, CAD models account for only the designed scaffold macroporosity and do not account for microporosity within the scaffold structure or surface roughness that are present due to the fabrication process.…”

mentioning

confidence: 99%

Predicting the Elastic Properties of Selective Laser Sintered PCL/β-TCP Bone Scaffold Materials Using Computational Modelling

2013

View full text Add to dashboard Cite

Publication InformationDoyle, H., Lohfeld, S., McHugh, P.E. (2013) 'Predicting the elastic properties of selective laser sintered PCL/b-TCP bone scaffold materials using computational modelling'. Annals Of Biomedical Engineering, 42 (3):661-677. Publisher SpringerLink to publisher's version http://link.springer.com/article/10.1007%2Fs10439-013-0913-4Item record http://hdl.handle.net/10379/5524 DOI http://dx.doi.org/10.1007/s10439-013-0913-4Accepted manuscript, published in Annals of Biomedical Engineering 09/2013; 42(3), pp 661-677. The final publication is available at Springer via http://dx.doi.org/10.1007/s10439-013-0913-4Title: Predicting the elastic properties of selective laser sintered PCL/β-TCP bone scaffold materials using computational modelling. AbstractThis study assesses the ability of finite element models to capture the mechanical behaviour of sintered orthopaedic scaffold materials. Individual scaffold struts were fabricated from a 50:50 wt% poly-ε-caprolactone (PCL) /β-tricalcium phosphate (β-TCP) blend, using selective laser sintering (SLS). The tensile elastic modulus of single struts was determined experimentally. High resolution finite element models of single struts were generated from micro-CT scans (28.8µm resolution) and an effective strut elastic modulus was calculated from tensile loading simulations. Three material assignment methods were employed: (1) homogeneous PCL elastic constants, (2) composite PCL/ β-TCP elastic constants based on rule of mixtures, and (3) heterogeneous distribution of micromechanically-determined elastic constants. In comparison with experimental results, the use of homogeneous PCL properties gave a good estimate of strut modulus; however it is not sufficiently representative of the real material as it neglects the β-TCP phase. The rule of mixtures method significantly overestimated strut modulus, while there was no significant difference between strut modulus evaluated using the micromechanically-determined elastic constants and experimentally evaluated strut modulus. These results indicate that the multi-scale approach of linking micromechancial modelling of the sintered scaffold material with macroscale modelling gives an accurate prediction of the mechanical behaviour of the sintered structure.Keywords: selective laser sintering; polycaprolactone, B-tricalcium phosphate; micromechanical modelling; bone tissue engineering; mechanical properties; finite element analysis.3 IntroductionThe purpose of bone tissue engineering scaffolds is to fill defects and support mechanical loading while providing a template on which new bone will form. The remodelling of native bone in response to mechanical loading occurs when cells convert mechanical stimuli to chemical signals to direct the formation of new tissue or resorption through mechanotransduction 30,44 . The mechanical stimuli that influence bone formation in vivo are a combination of both fluid shear over the cells 36,55 and mechanical loading of the cells 16,24,58 , therefore it is important to be able to acc...

show abstract

“…The biocompatibility of scaffolds has to be similar with the one of the human bone, from the mechanical, chemical and biological point of view [7]. Also the biocompatible material must have the possibility to perform as a substrate that will support the appropriate cellular activity and also to optimize tissue generation [8,9]. Other important characteristics are the biomechanical properties of the total hip replacement produced by SLS technology which should be the closest to the human bone properties.…”

Section: Introductionmentioning

confidence: 99%

The influence of build orientation on the mechanical properties of medical implants made from PA 2200 by Selective Laser Sintering

Păcurar

Petrilak

2017

MATEC Web Conf.

View full text Add to dashboard Cite

Abstract. This paper presents a series of research that have been made by the authors in the field of medical implants realized from PA 2200 powder material using the Selective Laser Sintering (SLS) method. Several sets of samples differently oriented into the working area of the machine were manufactured from PA 2200 by SLS, in order to determine which is the recommended orientation to be used during the manufacturing process, in such a way that at the end the mechanical properties (e.g. Compressive strength, Young's modulus, etc.) will be as closed as possible to the ones of the human bones. The obtained results were further on used in the case of a medical implant (Acetabular liner) that was manufactured at the Technical University of Cluj-Napoca (TUCN) from PA 2200 material using the DTM Sinterstation 2000 SLS equipment.

show abstract

Finite element predictions compared to experimental results for the effective modulus of bone tissue engineering scaffolds fabricated by selective laser sintering

Cited by 79 publications

References 13 publications

Fabrication, mechanical and in vivo performance of polycaprolactone/tricalcium phosphate composite scaffolds

Fabrication, mechanical and in vivo performance of polycaprolactone/tricalcium phosphate composite scaffolds

Predicting the Elastic Properties of Selective Laser Sintered PCL/β-TCP Bone Scaffold Materials Using Computational Modelling

The influence of build orientation on the mechanical properties of medical implants made from PA 2200 by Selective Laser Sintering

Contact Info

Product

Resources

About