Low-temperature inductively coupled plasma as a method to promote biomineralization on 3D printed poly(lactic acid) scaffolds

Silica-doped poly(lactic acid) (PLA) composite hollow spheres containing calcium carbonates (Si-CCPC spheres) were prepared using aminopropyltriethoxysilane (APTES) for injectable bone fillers combined with a cell-delivery system. Si-CCPC spheres have a hollow spherical shape of ~1 mm in the external diameter and an open channel in the shell, which is selfformed. The channel size is about 500 *m in diameter. X-ray energy dispersive spectroscopy (EDS) analysis showed incorporation of silicon in Si-CCPC spheres. After soaking Si-CCPC spheres in simulated body fluid (SBF), hydroxycarbonate apatite formed on the Si-CCPC spheres. Inductively coupled plasma atomic emission spectroscopy (ICP-AES) showed that the Si4+ ion is released from Si-CCPC spheres in SBF.

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Development of three-dimensional printing filaments based on poly(lactic acid)/hydroxyapatite composites with potential for tissue engineering

Journal of Composite Materials ◽

10.1177/0021998320988568 ◽

2021 ◽

pp. 002199832098856

Author(s):

Marcela Piassi Bernardo ◽

Bruna Cristina Rodrigues da Silva ◽

Luiz Henrique Capparelli Mattoso

Keyword(s):

Tissue Engineering ◽

Lactic Acid ◽

Fused Deposition Modeling ◽

Three Dimensional ◽

Poly Lactic Acid ◽

Scanning Calorimetry ◽

Three Dimensional Printing ◽

Fused Deposition ◽

Deposition Modeling ◽

3D Printed

Injured bone tissues can be healed with scaffolds, which could be manufactured using the fused deposition modeling (FDM) strategy. Poly(lactic acid) (PLA) is one of the most biocompatible polymers suitable for FDM, while hydroxyapatite (HA) could improve the bioactivity of scaffold due to its chemical composition. Therefore, the combination of PLA/HA can create composite filaments adequate for FDM and with high osteoconductive and osteointegration potentials. In this work, we proposed a different approache to improve the potential bioactivity of 3D printed scaffolds for bone tissue engineering by increasing the HA loading (20-30%) in the PLA composite filaments. Two routes were investigated regarding the use of solvents in the filament production. To assess the suitability of the FDM-3D printing process, and the influence of the HA content on the polymer matrix, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) were performed. The HA phase content of the composite filaments agreed with the initial composite proportions. The wettability of the 3D printed scaffolds was also increased. It was shown a greener route for obtaining composite filaments that generate scaffolds with properties similar to those obtained by the solvent casting, with high HA content and great potential to be used as a bone graft.

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Effects of Rice Straw Powder (RSP) Size and Pretreatment on Properties of FDM 3D-Printed RSP/Poly(Lactic Acid) Biocomposites

Molecules ◽

10.3390/molecules26113234 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3234

Author(s):

Wangwang Yu ◽

Lili Dong ◽

Wen Lei ◽

Yuhan Zhou ◽

Yongzhe Pu ◽

...

Keyword(s):

Lactic Acid ◽

Rice Straw ◽

Fused Deposition Modeling ◽

Flexural Modulus ◽

Tensile Modulus ◽

Cost Effective ◽

Poly Lactic Acid ◽

Fused Deposition ◽

Interfacial Compatibility ◽

3D Printed

To develop a new kind of environment-friendly composite filament for fused deposition modeling (FDM) 3D printing, rice straw powder (RSP)/poly(lactic acid) (PLA) biocomposites were FDM-3D-printed, and the effects of the particle size and pretreatment of RSP on the properties of RSP/PLA biocomposites were investigated. The results indicated that the 120-mesh RSP/PLA biocomposites (named 120#RSP/PLA) showed better performance than RSP/PLA biocomposites prepared with other RSP sizes. Infrared results showed that pretreatment of RSP by different methods was successful, and scanning electron microscopy indicated that composites prepared after pretreatment exhibited good interfacial compatibility due to a preferable binding force between fiber and matrix. When RSP was synergistically pretreated by alkaline and ultrasound, the composite exhibited a high tensile strength, tensile modulus, flexural strength, and flexural modulus of 58.59, 568.68, 90.32, and 3218.12 MPa, respectively, reflecting an increase of 31.19%, 16.48%, 18.75%, and 25.27%, respectively, compared with unmodified 120#RSP/PLA. Pretreatment of RSP also improved the thermal stability and hydrophobic properties, while reducing the water absorption of 120#RSP/PLA. This work is believed to provide highlights of the development of cost-effective biocomposite filaments and improvement of the properties of FDM parts.

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Ion Release from Dental Implants, Prosthetic Abutments and Crowns under Physiological and Acidic Conditions

Coatings ◽

10.3390/coatings11010098 ◽

2021 ◽

Vol 11 (1) ◽

pp. 98

Author(s):

María Arregui ◽

Florian Latour ◽

Francisco Javier Gil ◽

Román A. Pérez ◽

Luis Giner-Tarrida ◽

...

Keyword(s):

Lactic Acid ◽

Dental Implants ◽

Inductively Coupled Plasma ◽

Ion Concentration ◽

Ion Release ◽

Inductively Coupled ◽

Immersion Medium ◽

The Media ◽

Acidic Conditions ◽

Clinical Conditions

Ion release from dental implants and prosthetic restoration can affect osteointegration and implant viability over a long period of time. Therefore, the aim of this study was to study the ion release from implants and crowns, with and without intermediate anodized abutments, in two different media, simulating clinical conditions. The implants, intermediate prosthetic abutments and Cr–Co crowns were divided into two groups depending on the media: Hanks’ solution and 1% lactic acid, simulating body fluids and microbiologically conditioned fluids, respectively. The study followed the ISO 10271:2011 and 10993-15:2000 standards modified to simulate the replacement of fluids in the oral environment. The ions’ release was measured by inductively coupled plasma mass spectroscopy (ICP-EOS), and only aluminum, chromium, cobalt, titanium and vanadium were identified. Ion concentration was higher in lactic acid than in Hanks’ solution at all time points (p < 0.05). Only vanadium showed a very low ion release in lactic acid, with no statistically significant differences from the ion release in Hanks’ solution (p = 0.524). Both anodized abutments and the immersion medium influenced the release of ions and affected the corrosion of these structures. The presence of an intermediate anodized abutment also affected ion release, as the level of ions was lower in groups with this component.

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Evaluation of a poly(lactic-acid) scaffold filled with poly(lactide-co-glycolide)/hydroxyapatite nanofibres for reconstruction of a segmental bone defect in a canine model

Veterinární Medicína ◽

10.17221/80/2019-vetmed ◽

2019 ◽

Vol 64 (No. 12) ◽

pp. 531-538

Author(s):

JW Yun ◽

SY Heo ◽

MH Lee ◽

HB Lee

Keyword(s):

Lactic Acid ◽

Bone Defect ◽

Bone Defects ◽

Bone Morphogenetic Protein 2 ◽

Poly Lactic Acid ◽

Micro Computed Tomography ◽

Bone Parameters ◽

3D Printed ◽

Group 3 ◽

Group 2

Critical-sized bone defects are a difficult problem in both human and veterinary medicine. To address this issue, synthetic graft materials have been garnering attention. Abundant in vitro studies have proven the possibilities of poly(lactic-acid) (PLA) scaffolds and poly(lactide-co-glycolide)/hydroxyapatite (PLGA/HAp) nanofibres for treating bone defects. The present study aimed at conducting an in vivo assessment of the biological performance of a three dimensional (3D)-printed PLA scaffold filled with a PLGA/HAp nanofibrous scaffold to estimate its potential applications in bone defect reconstruction surgery. Defects were created in a 20 mm-long region of the radius bone. The defects created on the right side in six Beagle dogs (n = 6) were left untreated (Group 1). The defects on the left side (n = 6) were filled with 3D-printed PLA scaffolds incorporated with PLGA/Hap nanofibres with gelatine (Group 2). The other six Beagle dog defects were made bilaterally (n = 12) and filled with the same material as that used in Group 2 along with recombinant bone morphogenetic protein 2 (rhBMP-2) (Group 3). Both the radiological and histological examinations were performed for observing the reaction of the scaffold and the bone. Micro-computed tomography (CT) was utilised for the evaluation of the bone parameters 20 weeks after the experiment. The radiological and histological results revealed that the scaffold was biodegradable and was replaced by new bone tissue. The micro-CT revealed that the bone parameters were significantly (P < 0.05) increased in Group 3. Based on these results, our study serves as a foundation for future studies on bone defect treatment using synthetic polymeric scaffolds.

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