Degradation, Bone Regeneration and Tissue Response of an Innovative Volume Stable Magnesium-Supported GBR/GTR Barrier Membrane

Abstract

Introduction: Bioresorbable collagenous barrier membranes are used to prevent premature soft tissue ingrowth and to allow bone regeneration. For volume stable indications, only non-absorbable synthetic materials are available. This study investigates a new bioresorbable hydrofluoric acid (HF)-treated magnesium (Mg) mesh in a native collagen membrane for volume stable situations. Materials and Methods: HF-treated and untreated Mg were compared in direct and indirect cytocompatibility assays. In vivo, 18 New Zealand White Rabbits received each four 8 mm calvarial defects and were divided into four groups: (a) HF-treated Mg mesh/collagen membrane, (b) untreated Mg mesh/collagen membrane (c) collagen membrane and (d) sham operation. After 6, 12 and 18 weeks, Mg degradation and bone regeneration was measured using radiological and histological methods. Results: In vitro, HF-treated Mg showed higher cytocompatibility. Histopathologically, HF-Mg prevented gas cavities and was degraded by mononuclear cells via phagocytosis up to 12 weeks. Untreated Mg showed partially significant more gas cavities and a fibrous tissue reaction. Bone regeneration was not significantly different between all groups. Discussion and Conclusions: HF-Mg meshes embedded in native collagen membranes represent a volume stable and biocompatible alternative to the non-absorbable synthetic materials. HF-Mg shows less corrosion and is degraded by phagocytosis. However, the application of membranes did not result in higher bone regeneration.

Biocompatibility and Immune Response of a Newly Developed Volume-Stable Magnesium-Based Barrier Membrane in Combination with a PVD Coating for Guided Bone Regeneration (GBR)

“…Cytocompatibility analysis was conducted in accordance with the ISO 10993-5/-12 as described in our previous publications [ 5 , 29 , 30 , 31 ]. Therefore, the process is briefly summarized:…”

“…The in vivo study was conducted at the Faculty of Medicine (University of Niš, Niš, Serbia) following a previously described protocol following authorization by the local ethical committee (Faculty of Medicine, University of Niš, Niš, Serbia) on the basis of which the Veterinary Directorate of the Ministry of Agriculture, Forestry and Water Management of the Republic of Serbia issued the decision number 323-07-00278/2017-05/6 (Date: 13/07/2017) [ 2 , 5 , 6 , 21 , 22 ]. Thereby, the experimental animals were housed using standard conditions, i.e., water ad libitum, artificial light and regular rat pellets, in combination with standard pre- and postoperative care.…”

“…To overcome the limitations of the currently used non-resorbable barrier membranes, a new generation of membranes has been introduced, combining the advantages of resorbability with volume stability. An initial step in this direction was reported in a publication by Barbeck et al that showed the good biocompatibility of a new bioresorbable barrier membrane composed of a hydrofluoric acid (HF)-treated magnesium (Mg) mesh embedded in a native collagen membrane for volume stable indications [ 5 , 6 ]. In this study, the HF-treatment was applied for passivation of the implanted magnesium meshes to slow down its biodegradation as it is known that the application of pure magnesium implants may lead to their rapid uncontrolled degradation along with hydrogen gas evolution and related tissue incompatibilities [ 5 ].…”

“…An initial step in this direction was reported in a publication by Barbeck et al that showed the good biocompatibility of a new bioresorbable barrier membrane composed of a hydrofluoric acid (HF)-treated magnesium (Mg) mesh embedded in a native collagen membrane for volume stable indications [ 5 , 6 ]. In this study, the HF-treatment was applied for passivation of the implanted magnesium meshes to slow down its biodegradation as it is known that the application of pure magnesium implants may lead to their rapid uncontrolled degradation along with hydrogen gas evolution and related tissue incompatibilities [ 5 ]. In this context, a variety of coatings have been analyzed for their suitability to enable the safe application of magnesium implants [ 5 , 7 , 8 ].…”

“…In this study, the HF-treatment was applied for passivation of the implanted magnesium meshes to slow down its biodegradation as it is known that the application of pure magnesium implants may lead to their rapid uncontrolled degradation along with hydrogen gas evolution and related tissue incompatibilities [ 5 ]. In this context, a variety of coatings have been analyzed for their suitability to enable the safe application of magnesium implants [ 5 , 7 , 8 ]. Interestingly, most of the coatings are based on (calcium) phosphate compounds and are thus not suitable for combination with a magnesium-based barrier membrane due to their brittleness and inflexibility [ 7 , 9 , 10 ].…”