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.

Original 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

English

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.

Keywords

cranial trauma; rehabilitation; osteotomy; 3D printing; patient-specific modelling

Authors

RIDWAN-PRAMANA, A.; MARCIÁN, P.; BORÁK, L.; NARRA, N.; FOROUZANFAR, T.; WOLFF, J.

Released

1. 1. 2016

Publisher

CHURCHILL LIVINGSTONE

Location

Scotland

ISBN

1010-5182

Periodical

JOURNAL OF CRANIO-MAXILLOFACIAL SURGERY

Year of study

44

Number

1

State

United Kingdom of Great Britain and Northern Ireland

Pages from

34

Pages to

44

Pages count

10

URL

http://www.sciencedirect.com/science/article/pii/S1010518215003546

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",
  journal="JOURNAL OF CRANIO-MAXILLOFACIAL SURGERY",
  year="2016",
  volume="44",
  number="1",
  pages="34--44",
  doi="10.1016/j.jcms.2015.10.014",
  issn="1010-5182",
  url="http://www.sciencedirect.com/science/article/pii/S1010518215003546"
}