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Jacobs Journal of Medical Diagnosis and Medical Imaging
A Tissue-Equivalent Phantom for the X-ray Evaluation of Polymeric Orthopedic
Implants with Osseointegrative Coating
Francesco Tessarolo
1,2*
, Nicola Pace
2
, Gloria Miori
3,4
, Giandomenico Nollo
1,2
, Mauro Recla
5
, Aldo Valentini
3
1
Department of Industrial Engineering, University of Trento, Trento, Italy
2
Healthcare Research and Innovation Program (IRCS-FBK-PAT), Bruno Kessler Foundation, Trento, Italy
3
Department of Health Physics, Azienda Provinciale per i Servizi Sanitari, Trento, Italy
4
School of Medical Physics, University of Roma Tor Vergata, Rome, Italy
5
Division of Diagnostic Radiology, S. Chiara Hospital, Trento, Italy
*Corresponding author: Dr. Francesco Tessarolo, Healthcare Research and Innovation Program (IRCS-FBK-PAT), Bruno Kessler
Foundation & Department of Industrial Engineering, University Of Trento via delle Regole, 101, I-38123, Mattarello, Trento, Italy,
Phone: +39 0461 282775; Fax: +39 0461283659; E-mail: tessaro@science.unitn.it, tessarolo.f@gmail.com
Received: 09-13-2016
Accepted: 10-18-2016
Published: 11-03-2016
Copyright: © 2016 Francesco Tessarolo
Abstract
Purpose
Orthopaedics polymeric implants made of ultra-high molecular-weight polyethylene (UHMWPE), polyether-ether-ketone
(PEEK) or its carbon-fiber reinforced composite (CFR-PEEK) can be coated with titanium (Ti) or hydroxyapatite (HA) by com-
pression-moulding or plasma-spray techniques for bone integration. The coating may also improve the radiological properties
of the implanted device. This work aimed at developing a tissue-equivalent phantom for measuring the radiological contrast
given by different polymeric materials coated with Ti or HA for orthopedic implant applications.
Methods
A modular phantom was designed to simulate the human hip, differentiating soft tissue, trabecular and cortical bone. Seven
different substrate-coating combinations were considered for X-ray contrast measurement. Substrate thickness was also varied
resulting in 28 tested coupons. Radiographic images were obtained by a state-of-the-art clinical radiography unit. Contrast val-
ues were compared to a threshold for detectability.
Results
The tissue equivalent phantom allowed rapid coupon exchange and acquisition of multiple X-rays-images in a short period of
time. Coupons contrast ranged from 0.02 to 0.27 depending on the combination of polymer type, substrate thickness, coating
composition, thickness and porosity. Eighteen coupons showed a contrast higher than the predefined threshold. Thin titanium
coatings resulted in a sufficient contrast when deposited on PEEK or CFR-PEEK thicker than 10 mm. Medium thickness coatings
with low porosity and thick coatings with high porosity were above the threshold when associated to polymeric substrates with
a thickness of 8 mm or more. Differently, pre-sintered grid made of titanium alloy was clearly distinguished even when associ-
ated to only 6 mm thin UHMWPE.
Research Article
Cite this article: Francesco Tessarolo. A Tissue-Equivalent Phantom for the X-ray Evaluation of Polymeric Orthopedic Implants with Osseointegrative Coating.
J J Med Diagnosis and Image. 2016, 2(1): 014. 1 1(1):014.