title: Hydrogel tissue expanders for stomatology. Part I. Methacrylate-based polymers.
abstract: In order to create a soft tissue surplus, implantable volume expanders are often utilized in dental surgery. Implanted tissue expanders should gradually increase their volume, exerting a constant pressure on the surrounding tissue for weeks. Current tissue expanders are based predominantly on externally inflatable balloons or on osmotically active tissue expanders that use soft hydrogels wrapped in perforated plastic coatings, which limit fluid entry and swelling. We have designed and examined tissue expanders based on the controlled rate expansive hydrogels synthesized from copolymers of selected methacrylates and N-vinylpyrrolidone, cross-linked with a combination of non-degradable (glycol dimethacrylates) and hydrolytically degradable (N,O-dimethacryloylhydroxylamine) cross-linkers. These copolymers have close-to-linear volume expansion rates (up to 6-9 times their original volume) and exert an increasing swelling pressure in vitro. The anesthetic benzocaine has been incorporated into the hydrogels, and kinetic release experiments have shown that most of the drug (90%) was released within 48 h. Our proposed hydrogel expanders are homogeneous and have suitable mechanical properties, thus simplifying the surgical manipulations required. Further studies will be needed to completely evaluate their biocompatibility and tissue response to the implants.
authors.affiliation: Institute of Macromolecular Chemistry AS CR, Heyrovsky Sq. 2, Prague 6, 162 06, Czech Republic.
authors.forename: Jakub
authors.initials: J
authors.lastname: Hrib
authors.affiliation: Institute of Macromolecular Chemistry AS CR, Heyrovsky Sq. 2, Prague 6, 162 06, Czech Republic. sirc@imc.cas.cz.
authors.forename: Jakub
authors.initials: J
authors.lastname: Sirc
authors.affiliation: Institute of Hematology and Blood Transfusion, U Nemocnice 2094/1, Prague 2, 128 20, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Lesny
authors.affiliation: Institute of Macromolecular Chemistry AS CR, Heyrovsky Sq. 2, Prague 6, 162 06, Czech Republic.
authors.forename: Radka
authors.initials: R
authors.lastname: Hobzova
authors.affiliation: Institute of Macromolecular Chemistry AS CR, Heyrovsky Sq. 2, Prague 6, 162 06, Czech Republic.
authors.forename: Miroslava
authors.initials: M
authors.lastname: Duskova-Smrckova
authors.affiliation: Institute of Macromolecular Chemistry AS CR, Heyrovsky Sq. 2, Prague 6, 162 06, Czech Republic.
authors.forename: Jiri
authors.initials: J
authors.lastname: Michalek
authors.affiliation: First Medical Faculty of the Charles University, Katerinska 32, Prague 2, 121 08, Czech Republic.
authors.forename: Roman
authors.initials: R
authors.lastname: Smucler
mesh_terms: D000777:Anesthetics / Q000008:administration & dosage; D001672:Biocompatible Materials / Q000737:chemistry; D003432:Cross-Linking Reagents / Q000737:chemistry; D006801:Humans; D020100:Hydrogels / Q000737:chemistry*; D006898:Hydroxylamines / Q000737:chemistry; D007700:Kinetics; D008689:Methacrylates / Q000737:chemistry*; D019242:Oral Medicine / Q000379:methods*; D011108:Polymers / Q000737:chemistry*; D011312:Pressure; D015625:Tissue Expansion Devices
chemical_list: D000777:Anesthetics; D001672:Biocompatible Materials; D003432:Cross-Linking Reagents; D020100:Hydrogels; D006898:Hydroxylamines; D008689:Methacrylates; C494687:N,O-dimethacryloylhydroxylamine; D011108:Polymers