Patient-Specific Bioimplants and Reconstruction Plates for Mandibular Defects: Production Workflow and In Vivo Large Animal Model Study

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A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
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Macromolecular Bioscience, articlenumber 2100398
A major challenge with extensive craniomaxillofacial bone reconstruction is the limited donor-site availability to reconstruct defects predictably and accurately according to the anatomical shape of the patient. Here, patient-specific composite bioimplants, consisting of cross-linked poly(trimethylene carbonate) (PTMC) networks and β-tricalcium phosphate (β-TCP), are tested in vivo in twelve Göttingen minipigs in a large mandibular continuity defect model. The 25 mm defects are supported by patient-specific titanium reconstruction plates and receive either osteoconductive composite bioimplants (PTMC+TCP), neat polymer network bioimplants (PTMC), autologous bone segments (positive control), or are left empty (negative control). Postoperatively, defects treated with bioimplants show evident ossification at 24 weeks. Histopathologic evaluation reveals that neat PTMC bioimplant surfaces are largely covered with fibrous tissue, while in the PTMC+TCP bioimplants, bone attached directly to the implant surface shows good osteoconduction and histological signs of osteoinductivity. However, PTMC+TCP bioimplants are associated with high incidence of necrosis and infection, possibly due to rapid resorption and/or particle size of the used β-TCP. The study highlights the importance of testing bone regeneration implants in a clinically relevant large animal model and at the in situ reconstruction site, since results on small animal models and studies in nonloadbearing areas do not translate directly.
Funding Information: A.A.‐S and R.K. contributed equally to this work as first authors. R.S.‐K, J.S., and B.M. contributed equally to this work as senior authors. The project was funded by Business Finland (CraMaxS 557/31/2016) and was implemented in collaboration between University of Helsinki, Aalto University, and Helsinki University Hospital in cooperation with Planmeca Oy, DeskArtes Oy, Versoteq 3D Solutions Oy, and Labquality Oy. Additional funds from the in vivo study were also received from Helsinki University Hospital State funding for university‐level health research (Grant Nos. Y1149SUL30, Y1014SL015, Y1014SULE1, TYH2018225, and TYH2019117). The authors kindly thank Stryker Ltd for craniomaxillofacial instrumentation used in surgical procedures, Dr. Heikki Suhonen X‐Ray Micro‐CT Laboratory for µCT expertise, staff at Large Animal Center for animal care, Veterinary Teaching Hospital for CT imaging, Finnish Centre for Laboratory Animal Pathology (FCLAP) for histopathological services and Genome Biology Unit for histology scanning, and all part of HiLIFE University of Helsinki. Ashish Mohite from Aalto University School of ARTS supported the research with modelling expertise. This work made use of Aalto University Bioeconomy Facilities. Publisher Copyright: © 2022 The Authors. Macromolecular Bioscience published by Wiley-VCH GmbH
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Dienel , K , Abu-Shahba , A , Kornilov , R , Björkstrand , R , van Bochove , B , Snäll , J , Wilkman , T , Mesimäki , K , Meller , A , Lindén , J , Lappalainen , A , Partanen , J , Seppänen-Kaijansinkko , R , Seppälä , J & Mannerström , B 2022 , ' Patient-Specific Bioimplants and Reconstruction Plates for Mandibular Defects: Production Workflow and In Vivo Large Animal Model Study ' , Macromolecular Bioscience , vol. 22 , no. 4 , 2100398 .