In Vitro and in Vivo Study of Poly(Lactic–co–Glycolic) (PLGA) Membranes Treated with Oxygen Plasma and Coated with Nanostructured Hydroxyapatite Ultrathin Films for Guided Bone Regeneration Processes

Abstract

Abstract:The novelty of this study is the addition of an ultrathin layer of nanostructured hydroxyapatite (HA) on oxygen plasma modified poly(lactic-co-glycolic) (PLGA) membranes (PO 2 ) in order to evaluate the efficiency of this novel material in bone regeneration. Methods: Two groups of regenerative membranes were prepared: PLGA (control) and PLGA/PO 2 /HA (experimental). These membranes were subjected to cell cultures and then used to cover bone defects prepared on the skulls of eight experimental rabbits. Results: Cell morphology and adhesion of the osteoblasts to the membranes showed that the osteoblasts bound to PLGA were smaller and with a lower number of adhered cells than the osteoblasts bound to the PLGA/PO 2 /HA membrane (p < 0.05). The PLGA/PO 2 /HA membrane had a higher percentage of viable cells bound than the control membrane (p < 0.05). Both micro-CT and histological evaluation confirmed that PLGA/PO 2 /HA membranes enhance bone regeneration. A statistically significant difference in the percentage of osteoid area in relation to the total area between both groups was found. Conclusions: The incorporation of nanometric layers of nanostructured HA into PLGA membranes modified with PO 2 might be considered for the regeneration of bone defects. PLGA/PO 2 /HA membranes promote higher osteosynthetic activity, new bone formation, and mineralisation than the PLGA control group.

Nanostructured surface bioactive composite scaffold for filling of bone defects

“…In particular O1s envelope of HA bare sample shows a major component at about 531.2eV attributable to the PO bonding and a minor at about 532eV related to C-O moieties. [41] After the surface modification with PCL the third component at about 533.5eV typical of C-O bond in PCL is observed. Moreover, the component at 532.15 related to C=O bonds is also observed, whilst the component related to the P-O moieties is slightly shifted toward lower binding energy (about 530.5eV) indicating a possible distortion of the HA structure.…”

In Vitro Comparative Study of Oxygen Plasma Treated Poly(Lactic–Co–Glycolic) (PLGA) Membranes and Supported Nanostructured Oxides for Guided Bone Regeneration Processes

“…The amplification of a band of approximately 500 bp was performed according to eight species of mycoplasma ( M. hyorhinis , M. arginini , M. pneumoniae , M. fermentans , M. orale , M. pirum , Acholeplasma laidlawii , and Spiroplasma mirum ) using a single pair of oligonucleotides corresponding to the 16S RNA. PCR was performed by taking an aliquot of the conditioned medium from the cells in culture after at least 48 h of culture [ 4 , 8 , 9 ]. MG-63 cells were cultured on control and experimental membranes.…”

“…Forty 50 µm thick resorbable inert PLGA scaffolds based on poly(lactic–co–glycolic) acid were fabricated using polycondensation (Institute of Materials Science, Seville, Spain). For the preparation of the membranes, 10 mL of a solution of PLGA (PLGA pellets with a copolymer ratio of 75:25 (lactic/glycolic acid) from Sigma-Aldrich Inc., St. Louis, MO, USA) in 1.5% dichloromethane was prepared by evaporation of the solvent on a Teflon plate for 48 h in air at room temperature, obtaining a film of a suitable consistency [ 4 ].…”

“…Numerous published studies have focused on the in vitro and in vivo effect of modified PLGA by means of processes that allow its roughness to increase [ 4 , 5 , 6 , 7 ]. As it is well known, the internal cellular organization and its orientation are controlled by focal adhesions that mediate the regulating effects of the adhesion of the extracellular matrix.…”

“…As it is well known, the internal cellular organization and its orientation are controlled by focal adhesions that mediate the regulating effects of the adhesion of the extracellular matrix. The distribution of the actin-myosin fibers depending on the properties of the surface is based on integrins that serve as mechanosensors, converting the mechanical signals of the medium into biological signals [ 4 ]. This scientific and biological evidence has allowed us to consider that the induction of the cellular activity of the osteoblasts can be further improved by modifying not only the roughness of the biomaterial surface, but also by the deposition of nanostructured coatings [ 5 ].…”