‘Reliability of new poly (lactic-co-glycolic acid) membranes treated with oxygen plasma plus silicon dioxide layers for pre-prosthetic guided bone regeneration processes’

Abstract

BackgroundThe use of cold plasmas may improve the surface roughness of poly(lactic-co-glycolic) acid (PLGA) membranes, which may stimulate the adhesion of osteogenic mediators and cells, thus accelerating the biodegradation of the barriers. Moreover, the incorporation of metallic-oxide particles to the surface of these membranes may enhance their osteoinductive capacity. Therefore, the aim of this paper was to evaluate the reliability of a new PLGA membrane after being treated with oxygen plasma (PO2) plus silicon dioxide (SiO2) layers for guided bone regeneration (GBR) processes.Material and MethodsCircumferential bone defects (diameter: 11 mm; depth: 3 mm) were created on the top of eight experimentation rabbits’ skulls and were randomly covered with: (1) PLGA membranes (control), or (2) PLGA/PO2/SiO2 barriers. The animals were euthanized two months afterwards. A micromorphologic study was then performed using ROI (region of interest) colour analysis. Percentage of new bone formation, length of mineralised bone, concentration of osteoclasts, and intensity of ostheosynthetic activity were assessed and compared with those of the original bone tissue. The Kruskal-Wallis test was applied for between-group com Asignificance level of a=0.05 was considered.ResultsThe PLGA/PO2/SiO2 membranes achieved the significantly highest new bone formation, length of mineralised bone, concentration of osteoclasts, and ostheosynthetic activity. The percentage of regenerated bone supplied by the new membranes was similar to that of the original bone tissue. Unlike what happened in the control group, PLGA/PO2/SiO2 membranes predominantly showed bone layers in advanced stages of formation.ConclusionsThe addition of SiO2 layers to PLGA membranes pre-treated with PO2 improves their bone-regeneration potential. Although further research is necessary to corroborate these conclusions in humans, this could be a promising strategy to rebuild the bone architecture prior to rehabilitate edentulous areas. Key words:Guided bone regeneration (GBR), poly(lactic-co-glycolic acid) (PLGA), membrane; oxygen plasma (PO2), nanocomposite, silicon dioxide layers.

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

“…Figure 4 shows the macroscopic appearance of the PLGA membranes before and after surface treatment with oxygen plasma. Additional information about the PLGA membranes after and before the oxygen plasma treatments can be found elsewhere [1,2,[30][31][32][33]. Surface topography analysis also enables us to appreciate the considerable increase in surface roughness of the PLGA membrane after exposure to oxygen plasma, with an RMS roughness value greater than 300 nm, without affecting structural integrity.…”

“…Figure 4 shows the macroscopic appearance of the PLGA membranes before and after surface treatment with oxygen plasma. Additional information about the PLGA membranes after and before the oxygen plasma treatments can be found elsewhere [ 1 , 2 , 30 , 31 , 32 , 33 ].…”

“…The surgical procedure followed the same methodology as previously described [ 1 , 6 ]. The animals were immobilised, and their vital signs were checked.…”

“…The use of physical barriers to prevent the invasion of gingival and connective tissue cells into bone cavities during the healing process is called guided bone regeneration (GBR) [ 1 ]. Tissue engineering enables the fabrication of membranes that mimic the structural properties of the original tissues, providing stable support to the extracellular matrix [ 2 ].…”

Modifications of Polymeric Membranes Used in Guided Tissue and Bone Regeneration

“…Membranes that were conditioned with PO 2 and then incorporated with SiO 2 provided significantly higher bone regeneration and mineralised bone length. This kind of membrane also showed a better influence on osteoclast concentration and improved osteosynthetic activity [26]. It can be concluded that both SiO 2 and TiO 2 incorporation significantly influenced bone regeneration, and this can be a valuable direction of future clinical research on GBR membrane modification.…”