Self-inflating soft tissue expanders represent a valuable modality in reconstructive surgery. For this purpose, particularly synthetic hydrogels that increase their volume by swelling in aqueous environment are used. The current challenge in the field is to deliver a material with a suitable protracted swelling response, ideally with an induction period (for sutured wound healing) followed by a linear increase in volume lasting several days for required tissue reconstruction. Here, we report on synthesis, swelling, thermal, mechanical and biological properties of novel hydrogel tissue expanders based on poly(styrene-alt-maleic anhydride) copolymers covalently crosslinked with p-divinylbenzene. The hydrogels exerted hydrolysis-driven swelling response with induction period over the first two days with minimal volume change and gradual volume growth within 30 days in buffered saline solution. Their final swollen volume reached more than 14 times the dry volume with little dependence on the crosslinker content. The mechanical coherence of samples during swelling and in their fully swollen state was excellent, the compression modulus of elasticity being between 750 and 850 kPa. In vitro cell culture experiments and in vivo evaluation in mice models showed excellent biocompatibility and suitable swelling responses meeting thus the application requirements as soft tissue expanders.

• Klíčová slova
• biocompatibility, hydrogel, in vivo, mechanical properties, self-inflating tissue expander, styrene-maleic anhydride copolymers, swelling, volume expansion,
• Publikační typ
• časopisecké články MeSH

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.

• MeSH
• anestetika aplikace a dávkování   MeSH
• biokompatibilní materiály chemie   MeSH
• hydrogely chemie   MeSH
• hydroxylaminy chemie   MeSH
• kinetika MeSH
• lidé MeSH
• methakryláty chemie   MeSH
• polymery chemie   MeSH
• reagencia zkříženě vázaná chemie   MeSH
• stomatologie metody   MeSH
• tkáňové expandéry * MeSH
• tlak MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• anestetika MeSH
• biokompatibilní materiály MeSH
• hydrogely MeSH
• hydroxylaminy MeSH
• methakryláty MeSH
• N,O-dimethacryloylhydroxylamine MeSH Prohlížeč
• polymery MeSH
• reagencia zkříženě vázaná MeSH