Bone Regeneration after Treatment with Covering Materials Composed of Flax Fibers and Biodegradable Plastics: A Histological Study in Rats

Abstract

The aim of this study was to examine the osteogenic potential of new flax covering materials. Bone defects were created on the skull of forty rats. Materials of pure PLA and PCL and their composites with flax fibers, genetically modified producing PHB (PLA-transgen, PCL-transgen) and unmodified (PLA-wt, PCL-wt), were inserted. The skulls were harvested after four weeks and subjected to histological examination. The percentage of bone regeneration by using PLA was less pronounced than after usage of pure PCL in comparison with controls. After treatment with PCL-transgen, a large amount of new formed bone could be found. In contrast, PCL-wt decreased significantly the bone regeneration, compared to the other tested groups. The bone covers made of pure PLA had substantially less influence on bone regeneration and the bone healing proceeded with a lot of connective tissue, whereas PLA-transgen and PLA-wt showed nearly comparable amount of new formed bone. Regarding the histological data, the hypothesis could be proposed that PCL and its composites have contributed to a higher quantity of the regenerated bone, compared to PLA. The histological studies showed comparable bone regeneration processes after treatment with tested covering materials, as well as in the untreated bone lesions.

In vivo analysis of covering materials composed of biodegradable polymers enriched with flax fibers

“…In a previous study, we could not detect any enhanced inflammation after insertion these materials on the cranial bone of rat [36]. Thus, the objective of this study was the investigation of the influence of the bioactive composites on the surrounding muscle and connective tissue.…”

Biomaterial design strategies to address obstacles in craniomaxillofacial bone repair

“…34 Additionally, most metals have a risk of corrosion and metal ion release, as well as mismatched mechanics compared to bone, which can lead to surrounding bone atrophy. [39][40][41] Generally, metals are limited for use in permanent xation for high loading applications, such as long bone fractures, as opposed to CMF defects. The non-degradable nature of metals also limits their use in pediatric patients due to facial deformities arising from restriction of the growing and developing skull and migration of the metal screws and plates during this process.…”

“…Two of the most commonly used polymers are FDA approved polycaprolactone (PCL) and poly(lactic acid) (PLA), which can degrade in the body via hydrolysis, but their degradation byproducts are acidic, and in high enough quantities may damage cells. 39,57,58 Both polymers are biodegradable and biocompatible, but PLA offers high mechanical strength and shorter degradation times, while PCL offers exibility and hydrophobicity. 59 Due to these disadvantages, PLA and PCL have been combined to create polymer blends to leverage the best qualities of both polymers to optimize degradation time and improve mechanical properties and exibility of the resulting material.…”

Properties and Degradation of Novel Fully Biodegradable PLA/PHB Blends Filled with Keratin

“…Great attention has been paid to PLA due to its thermoplastic behavior, biocompatibility and physical properties, and the ability to tune these properties by the addition of plasticizers (glycerol, triacetine, PEG, citrate esters, oils) [ 2 , 3 , 4 , 5 , 6 ], fillers (clay [ 7 , 8 ], carbon black [ 9 , 10 ], silica [ 11 , 12 , 13 ]), compatibilizers (tri-block copolymer PLA-PBAT-PLA [ 14 ], PLA-g-PEG [ 15 ]) or polymers (PHB [ 1 , 16 , 17 , 18 ], PBAT [ 19 ]). These additives lead to its increasing applicability in many industries, such as packaging [ 18 , 20 , 21 ], agriculture [ 1 , 16 , 22 ] and medicine [ 23 , 24 , 25 ]. In addition, the incorporation of functional fillers in the PLA matrix could significantly improve the physical properties as well as the structural characteristics that play key roles in various applications, for example in tissue engineering [ 26 ].…”