Extraordinary biological properties of a new calcium hydroxyapatite/poly(lactide-co-glycolide)-based scaffold confirmed by in vivo investigation

Abstract

This study examined the potential of a new porous calcium hydroxyapatite scaffold covered with poly (lactide-co-glycolide) (PLGA) as a bone substitute, identifying its advantages over Geistlich Bio-Oss®, considered the gold standard, in in vivo biofunctionality investigations. Structural and morphological properties of the new scaffold were analyzed by scanning electron and atomic force microscopy. The biofunctionality assays were performed on New Zealand white rabbits using new scaffold for filling full-thickness defects of critical size. The evaluated parameters were: the presence of macrophages, giant cells, monoocytes, plasma cells, granulocytes, neoangiogenesis, fibroplasia, and the percentage of mineralization. Parallel biofunctionality assays were performed using Geistlich Bio-Oss®. The appearance of bone defects 12 weeks after the new scaffold implantation showed the presence of a small number of typical immune response cells. Furthermore, significantly reduced number of capillary buds, low intensity of fibroplasia and high degree of mineralization in a lamellar pattern indicated that the inflammation process has been almost completely overcome and that the new bone formed was in the final phase of remodeling. All biofunctionality assays proved the new scaffold's suitability as a bone substitute for applications in maxillofacial surgery. It showed numerous biological advantages over Geistlich Bio-Oss® which was reflected mainly as a lower number of giant cells surrounding implanted material and higher degree of mineralization in new formed bone.

Stem cells in tissue engineering – dynamic cultivation requirement

“…However, problems such as variability and the potential of xenogenic media components to cause disease limit their use [15,16]. Synthetic polymers (polyethylene glycol, poly-l-lysine, poly-lactic acid, polyglycolic acid, and poly-dl-lactic acid-co-glycolic acid) are the group of artificially made scaffolds with different mechanical properties (pore size, elasticity, adhesion, tensile strength) [17][18][19][20][21][22]. Biodegradable, porous scaffolds represent the most promising in vitro imitation of SC niche that provides physical support, enables cell growth, regeneration and neovascularization, while they were replaced in time with new bone [23, 24,25].…”

“…Biodegradable, porous scaffolds represent the most promising in vitro imitation of SC niche that provides physical support, enables cell growth, regeneration and neovascularization, while they were replaced in time with new bone [23, 24,25]. Innovative scaffold construction that consists of ceramic part mimicking bone structure, and thin polymer layer above that contribute its' better mechanical properties and biocompatibility, showed to be very promising biomaterial for bone tissue engineering ( Figure 1) [21,25,26]. Scaffolds are commonly used as carriers that mimic ECM, promote expansion, migration, and differentiation of SC.…”

Various methods of 3D and Bio-printing

“…Idealno, skafold treba da se potpuno resorbuje tokom integracije tkiva. Skafoldi izgrađeni od biomaterijala treba da imitiraju važne aspekte ciljnog tkiva, obnavljaju njihove funkcije i obezbeđuju okruženje pogodno za diferencijaciju i proliferaciju ćelija [3,4]. Tradicionalne tehnike koje se koriste za proizvodnju takvih skafolda su gasna pena, livenje rastvarača, vezivanje vlaknima, fazno odvajanje, čišćenje čestica i tehnike zamrzavanja, koji obezbeđuju makroskopsku strukturu skafolda, ali često nemaju osobenosti prirodnog tkiva [5].…”

“…Ideally, scaffold should be completely resorbed during tissue integration. Biomaterial scaffolds should mimic important aspects of targeted tissue, restoring their function and providing an environment suitable for cell differentiation and proliferation [3,4]. Traditional techniques used for production of such scaffolds are gas foaming, solvent casting, fiber bonding, phase separation, particulate leaching, and freeze drying techniques that provide macroscale scaffold features but often lack the complexity of native tissue [5].…”

The advantages and disadvantages of biodentine: Satisfactory mechanical properties and radiopacity not meeting ISO standard

“…Tremendous progress has been accomplished in last several decades in the field of materials science 1,2,3 . In dentistry, the concept of using inert materials for tissue repair has been replaced with strategy to find bioactive materials which positively interact with human tissues 4,5 .…”