Biologically active polyurethane compositions for bone plastic operations of the facial skeleton

Abstract

The problem of scientific investigations in the selection of fixators for osteosynthesis in treating ailments with fractures and deformities of the facial skeleton bones, which will require reconstructive surgery, is considered. Literature data on the use of various types of materials for osteosynthesis are given. It was established that the development of new biologically active composite materials for the production of bone plates for osteosynthesis, which would meet the basic requirements of bone surgery: biocompatibility, strength, flexibility, ability to biodegrade, stimulation of tissue regeneration and prolonged therapeutic action, is an urgent direction of modern science and practical medicine. To solve this problem, the use of fixation structures for osteosynthesis based on biodegraded epoxy polyurethane (EPU) composite material with bioactive action (EPU-HAP-LEV) is proposed. Biological activity is ensured by the presence of hydroxyapatite and levamisole fillers in the EPU composite. Representative results of physical-mechanical, physical-chemical, and medical-biological studies, which preceded clinical trials of the composite material EPU–HAP–LEV in the form of osseous plates for osteosynthesis, are given. According to the obtained results, the EPU–HAP–LEV composite material is non-toxic, biocompatible and bioactive, capable of biodegradation and prolonged release of levamisole, has the necessary strength characteristics (flexural strength - 27.1 MPa, tensile strength - 24 MPa, relative elongation at break 5.3 MPa), which made it possible to manufacture fixators for osteosynthesis in the maxillofacial area and allowed to recommend them for clinical use. In the clinic, 76 patients with facial skull fractures were treated with polymer plates with screws, which are made of the EPU-HAP-LEV composition. An example of the clinical use of bone plates for osteosynthesis made of EPU-LEV-HAP is presented and their compliance with the medical purpose, effectiveness in the surgical treatment of maxillofacial fractures in areas that do not bear a significant masticatory load, as well as in biomechanically stable fractures is established.