Iodixanol as a Contrast Agent in a Fibrin Hydrogel for Endodontic Applications

Abstract

The application of biomaterials used in regenerative endodontics should be traceable. In this study, we checked some basic effects of rendering a fibrin hydrogel radiopaque using an iodine-based contrast agent (iodixanol) approved for systemic application. Fibrin hydrogels were prepared from a fibrin sealant (Tisseel) using either an isotonic iodixanol solution (Visipaque 320, test) or Tris buffer (control) as a diluent. Gelation kinetics, radiopacity, and swelling of lyophilized hydrogels were tested using standard methods. Hydrogel structure was evaluated using scanning electron microscopy (SEM). Furthermore, iodixanol release from the test gels was assessed using spectrophotometry, and tissue compatibility was compared between test and control hydrogels using the chick chorioallantoic membrane (CAM) assay. Results were compared using pairwise t-test, p < 0.05. Iodixanol caused a 70-fold delay in gelation to 26 min in the test compared to the control hydrogels (22 ± 1 s). Radiopacity of the test gels was 1.9 ± 0.2 mm Al/mm, compared to zero in the control hydrogels. Lyophilized hydrogel swelling was strongly reduced when iodixanol was added to the hydrogel (p < 0.05). Test hydrogels had an altered SEM appearance compared to controls, and exhibited a reduced porosity. Iodixanol release from the test hydrogels reached 14.5 ± 0.5% after 120 h and then ceased. This release did not have any apparent toxic effect and neither affected the viability, nor the physiology or vascularization of the CAM of fertilized chicken eggs. Iodixanol can render a fibrin hydrogel radiopaque and maintains its tissue compatibility, yet impacts gelation kinetics and hydrogel porosity.

Enhancing X-ray Attenuation of 3D Printed Gelatin Methacrylate (GelMA) Hydrogels Utilizing Gold Nanoparticles for Bone Tissue Engineering Applications

“…al. [37] suggested iodixanol combined fibrin hydrogels for endodontic applications. Their ex vivo preliminary experiments in human teeth showed that the radiopacity of the fibrin hydrogels was only sufficient for correct localization of the implant.…”

“…Nonetheless, it was indicated that the characteristics of hydrogels dramatically changed due to the addition of the iodixanol CA. [37] In this study, it was crucial to preserve the physicochemical properties of the scaffolds and their cytocompatible characteristics. Thus, among different CAs, AuNPs have been utilized as a promising candidate due to their high X-ray attenuation, depending on their size and concentration [38].…”

Contrast‐enhanced micro‐CT to assess dental pulp tissue debridement in root canals of extracted teeth: a series of cascading experiments towards method validation

“…Radiopacity was determined using a standard set‐up as described previously (Hertig et al . 2017). In brief, electronic data sets were generated using a fixed unit (Trophy, Paris, France) at 65 kV, 8 mA and 0.22 s with a focus‐film distance of 25 cm and electronic sensors (Digora; Soredex, Tuusula, Finland).…”

Therapeutic potential of mesenchymal stem cell-derived extracellular vesicles in regenerative endodontics

“…The first time the allogeneic MSCs were used was to treat patients with osteogenesis imperfecta. The improvements in bone structure and function obtained were reported (Horwitz et al, 1999). Since then, MSCs have been used in a large number of different animal models and randomised clinical trials, including treatment of acute myocardial infarction, ischaemic stroke, acute kidney failure and Crohn ś disease as well as steroidrefractory acute graft-versus-host disease (acute GvHD), which arises as a side effect of allogeneic hematopoietic stem cell transplantation therapies (Giebel et al, 2017).…”

“…Importantly, fibrin gels are commercially available clinically approved biomaterials and appear to be suitable delivery vehicles for exosomes in pulp regenerative procedures. However, additional preclinical and clinical studies are needed, especially related to their thrombin/fibrinogen composition and other physicochemical features relating to a controllable application in the root canal system (Hertig et al, 2017).…”