Publication detail
Structural and mechanical implications of PMMA implant shape and interface geometry in cranioplasty – a finite element study
RIDWAN-PRAMANA, A. MARCIÁN, P. BORÁK, L. NARRA, N. FOROUZANFAR, T. WOLFF, J.
Czech title
Cranioplastiky vyráběné z PMMA různých tvarů a geometrií řešených pomocí MKP
English title
Structural and mechanical implications of PMMA implant shape and interface geometry in cranioplasty – a finite element study
Type
journal article in Web of Science
Language
en
Original abstract
This computational study investigates the effect of shape (defect contour curvature) and bone-implant interface (osteotomy angle) on the stress distribution within PMMA skull implants. Using finite element methodology, 15 configurations – combinations of simplified synthetic geometric shapes (circular, square, triangular, irregular) and interface angulations – were simulated under 50N static loads. Furthermore, the implant fixation devices were modelled and analysed in detail. Negative osteotomy configurations demonstrated the largest stresses in the implant (275 MPa), fixation devices (1258 MPa) and bone strains (0.04). The circular implant with zero and positive osteotomy performed well with maximum observed magnitudes of – implant stress (1.2 MPa and 1.2 MPa), fixation device stress (11.2 MPa and 2.2 MPa), bone strain (0.218e-3 and 0.750e-4). The results suggest that the preparation of defect sites is a critical procedure. Of the greatest importance is the angle at which the edges of the defect are sawed. If under an external load, the implant has no support from the interface and the stresses are transferred to the fixation devices. This can endanger their material integrity and lead to unphysiological strains in the adjacent bone, potentially compromising the bone morphology required for anchoring. These factors can ultimately weaken the stability of the entire implant assembly.
Czech abstract
Článek se zabývá výpočtovým modelováním kranioplastik vyráběných z PMMA. Řešena je problematika tvaru defektů a jejich rozhraní.
English abstract
This computational study investigates the effect of shape (defect contour curvature) and bone-implant interface (osteotomy angle) on the stress distribution within PMMA skull implants. Using finite element methodology, 15 configurations – combinations of simplified synthetic geometric shapes (circular, square, triangular, irregular) and interface angulations – were simulated under 50N static loads. Furthermore, the implant fixation devices were modelled and analysed in detail. Negative osteotomy configurations demonstrated the largest stresses in the implant (275 MPa), fixation devices (1258 MPa) and bone strains (0.04). The circular implant with zero and positive osteotomy performed well with maximum observed magnitudes of – implant stress (1.2 MPa and 1.2 MPa), fixation device stress (11.2 MPa and 2.2 MPa), bone strain (0.218e-3 and 0.750e-4). The results suggest that the preparation of defect sites is a critical procedure. Of the greatest importance is the angle at which the edges of the defect are sawed. If under an external load, the implant has no support from the interface and the stresses are transferred to the fixation devices. This can endanger their material integrity and lead to unphysiological strains in the adjacent bone, potentially compromising the bone morphology required for anchoring. These factors can ultimately weaken the stability of the entire implant assembly.
Keywords in Czech
kraniální trauma; rehabilitace; osteotomie; 3D tisk; patient-specific modelling
Keywords in English
cranial trauma; rehabilitation; osteotomy; 3D printing; patient-specific modelling
Released
01.01.2016
Publisher
CHURCHILL LIVINGSTONE
Location
Scotland
ISSN
1010-5182
Volume
44
Number
1
Pages from–to
34–44
Pages count
10
BIBTEX
@article{BUT117740,
author="Angela {Ridwan-Pramana} and Petr {Marcián} and Libor {Borák} and Nathaniel {Narra} and Tim {Forouzanfar} and Jan {Wolff},
title="Structural and mechanical implications of PMMA implant shape and interface geometry in cranioplasty – a finite element study",
year="2016",
volume="44",
number="1",
month="January",
pages="34--44",
publisher="CHURCHILL LIVINGSTONE",
address="Scotland",
issn="1010-5182"
}