1. Experimental procedure Sintering Temperature
In silico design of 3D-printed calcium-phosphate based dental biomaterials
Bingbing Liang1, Varun Manhas1, France Lambert2, Dorien Van Hede2 , Liesbet Geris1,3
1Biomechanics Research Unit, GIGA In Silico Medicine, Université de Liège, Belgium ; ²Dental Biomaterials Research Unit, University of Liège; 3Boimechanics Section, KU Leuven, Belgium
INTRODUCTION
Background
Calcium phosphate-based biomaterials are most frequently used filler material in dentistry
3D printing of CaP-based biomaterials allows optimizing the design of these biomaterials.
In silico modeling can be used as design tool
Visualization and prediction of biological processes
Design at different spatial levels
Micro/nano: biological processes
Macro: patient geometry
Aim of this study
Design a new generation of efficient ceramic dental biomaterial for different custom defects
Develop new design by computer modeling using material & 3D printing process parameters as variables
Build model using historic data available within the consortium, the literature and dedicated in vitro/in vivo experiments
In silico
Patient
3D print
In vitro
Implant
In vivo
MATERIALS & METHODS
Neotissue Growth model [2]
The level set method (LSM) is used to simulated neotissue growth by tracking the advection of the interface between neotissue and void space
Experimental procedure
Model equations, implementation details in [2]
: signed distance function (level set function)
n: normal to the computational domain W
Γ(t) : interface between neotissue Wnt and void Wv
vG : the interface advection velocity
nΓ : the normal to interface
k : curvature
2 mm
Pore shapes
Pore size
0.5/0.7/1/2mm
Materials
HA/HA-TCP
Sintering Temperature
1130/1230°C
Cell type
Human periosteum derived cells
RESULTS
Gyroid (cut view)
Dynamic simulation of neotissue growth (uncalibrated time)
2D hexagon
3D hexagon (cut view)
The model results
The experimental results (HA, 1130°C)
Qualitatively, the curvature-based principle seems to hold for the tested experimental condition. Quantitatively, a recalibration of the advection velocity needs to be performed as the current value (derived for Titanium scaffolds in [2]) is too high in comparison to the results obtained for the CaP scaffold.
DISCUSSION
REFERENCES
Repeat the in vitro experiments to confirm biological results
Calibrate the speed of neotissue growth based on experimental results
Add variables to definition of neotissue growth :
surface roughness (related to sintering T°& material)
calcium release rate (related to material)
Integrate findings of single channel geometry into complex 3D shapes, such as gyroid. Taking into account 3D printing parameters as constraints.
[1] Rumpler, M., Woesz, A., Dunlop, J. W. C., van Dongen, J. T., and Fratzl, P. (2008). The effect of geometry on three-dimensional tissue growth. J. Roy Soc Interface, 5(27):
[2] Guyot Y, Papantoniou I, Luyten FP, Geris L. (2016), Coupling curvature-dependent and shear stress-stimulated neotissue growth in dynamic bioreactor cultures: a 3D computational model of a complete scaffold. Biomech Model Mechanobiol. 15(1):169-80
CONTACT
B. Liang: ; L. Geris:
This work is part of BIOPTOS, a certified BioWin project financed by the Walloon region (DG06). BL is funded by the National Fund for Scientific Research FNRS (T )