Directed Osteoblast Adhesion at Particle Boundaries: Promises for Nanophase Metals

AbstractIn spite of under performance, metals and metal alloys are currently being used in orthopedic implantable devices. Poor osseointegration, severe stress shielding, bone cell death and eventual necrotic bone resulting from the generation of wear debris are known to be some of the reasons responsible for their under performance. In addition, metallic corrosion products may also initiate cancer. Steady growth in the use of metals in orthopedic applications inspired researchers to deal with these problems in an integrated way. When conventional Ti, Ti6Al4V, and CoCrMo surfaces were modified to the nano-range, this study showed increased percentages of osteoblast (bone forming cell) adhesion on nanophase metals. Moreover, larger amounts of osteoblast adhesion was related to quantitative increases in the total length of particle boundaries per unit area and the total number of pores between surface particles per unit area, and the surface particle boundary index (SPBI) of nanophase metals. Additionally, we have developed a novel anticarcinogenic orthopedic metalloid, selenium (Se). When micron range surface particles of Se compacts were modified to the nano-range by chemical etching, we found positive relationships between directed osteoblast adhesion and various particle boundary parameters mentioned above under in vitro conditions. These results provided the first evidence to utilize nanosurface Se as an anticarcinogenic and bio-inspiring material for future applications in orthopedic metallic devices.

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Electrically-Controlled Penicillin/Streptomycin Release from Nanostructured Polypyrrole Coated on Titanium for Orthopedic Implants

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.151.197 ◽

2009 ◽

Vol 151 ◽

pp. 197-202 ◽

Cited By ~ 6

Author(s):

Sirinrath Sirivisoot ◽

Rajesh A. Pareta ◽

Thomas J. Webster

Keyword(s):

Photoelectron Spectroscopy ◽

Orthopedic Implants ◽

Nanometer Scale ◽

Force Microscopy ◽

Atomic Force ◽

Osteoblast Adhesion ◽

Antibiotic Release ◽

Orthopedic Applications ◽

Scale Roughness

Implant infection leading to revision surgery can be avoided by incorporating controllable antibiotic release from titanium (Ti) implant surfaces. In this study, penicillin/streptomycin (P/S) and dexamethasone (Dex) were successfully immobilized via electropolymerization within polypyrrole membranes coated on the surface of Ti, which is widely used in orthopedic applications. In vitro results showed that greater numbers of osteoblasts adhered on these polymer-coated substrates than on currently-used unmodified Ti. X-ray photoelectron spectroscopy was used to monitor and compare the reaction effectiveness and the yield of electropolymerization. Polypyrrole membranes conjugated with P/S and Dex, and then coated with PLGA, all possessed nanometer scale roughness, as analyzed by atomic force microscopy. In summary, this study demonstrated that drugs incorporated within electroactive polypyrrole membranes, whose release was controlled by applying voltages, supported osteoblast adhesion and could potentially fight bacterial infection.

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Biocompatibility and Cellular Behavior of TiNbTa Alloy with Adapted Rigidity for the Replacement of Bone Tissue

Metals ◽

10.3390/met11010130 ◽

2021 ◽

Vol 11 (1) ◽

pp. 130

Author(s):

Mercè Giner ◽

Ernesto Chicardi ◽

Alzenira de Fátima Costa ◽

Laura Santana ◽

María Ángeles Vázquez-Gámez ◽

...

Keyword(s):

Cortical Bone ◽

Bone Tissue ◽

Stress Shielding ◽

Mechanical Resistance ◽

Cellular Behavior ◽

Biomechanical Behavior ◽

Functional Behavior ◽

Bone Replacement ◽

Osteoblast Adhesion

In this work, the mechanical and bio-functional behavior of a TiNbTa alloy is evaluated as a potential prosthetic biomaterial used for cortical bone replacement. The results are compared with the reference Ti c.p. used as biomaterials for bone-replacement implants. The estimated mechanical behavior for TiNbTa foams was also compared with the experimental Ti c.p. foams fabricated by the authors in previous studies. A TiNbTa alloy with a 20–30% porosity could be a candidate for the replacement of cortical bone, while levels of 80% would allow the manufacture of implants for the replacement of trabecular bone tissue. Regarding biocompatibility, in vitro TiNbTa, cellular responses (osteoblast adhesion and proliferation) were compared with cell growth in Ti c.p. samples. Cell adhesion (presence of filopodia) and propagation were promoted. The TiNbTa samples had a bioactive response similar to that of Ti c.p. However, TiNbTa samples show a better balance of bio-functional behavior (promoting osseointegration) and biomechanical behavior (solving the stress-shielding phenomenon and guaranteeing mechanical resistance).

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Development of Novel Nanostructured Tissue Engineering Scaffold Materials through Self-assembly for Bed-side Orthopedic Applications

MRS Proceedings ◽

10.1557/proc-0950-d15-08 ◽

2006 ◽

Vol 950 ◽

Cited By ~ 1

Author(s):

Lijie Zhang ◽

Sharwatie Ramsaywack ◽

Hicham Fenniri ◽

Thomas J. Webster

Keyword(s):

Electron Microscopy ◽

Self Assembly ◽

Bone Growth ◽

Building Blocks ◽

Bone Cell ◽

Hydrogel Scaffolds ◽

Hydrogel Matrix ◽

Dna Base Pair ◽

Orthopedic Applications

ABSTRACTThe objective of the current study was to utilize a natural self-assembled organic biomaterial (helical rosette nanotubes (HRNs)) to improve bone growth necessary for orthopedic implant applications. The DNA base pair building blocks of HRNs can self-assemble through 18 H-bonds to form a supermacrocycle in water which then stack to form a nanotube 3.5 nm in diameter and several μm in length. The nanometric features and ability to place diverse amino acid side chains on HRNs make them intriguing materials for orthopedic applications. In this study, HRNs are combined with a biocompatible hydrogel matrix in order to obtain more robust scaffolds. Bone cell experiments in vitro demonstrated that the novel HRNs with hydrogels could greatly enhance osteoblast (bone-forming cell) adhesion even at a very low concentration (close to 0.001mg/ml). Morphology of the HRNs with hydrogel scaffolds was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Results showed that there were bundles of nanotubes in the HRNs with hydrogel scaffolds. Therefore, considering the good biocompatibility and nano bone-like structure of these scaffolds, the nanostructured hydrogel matrix with HRNs have the potential to serve as novel bone building agents for “on-the-site” orthopedic applications.

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Increased Osteoblast Adhesion on Nanograined Hydroxyapatite and Tricalcium Phosphate Calcium Titanate Composites

MRS Proceedings ◽

10.1557/proc-0950-d15-20 ◽

2006 ◽

Vol 950 ◽

Author(s):

Huinan Liu ◽

Celaletdin Ergun ◽

John W. Halloran ◽

Thomas J. Webster

Keyword(s):

Tricalcium Phosphate ◽

Spray Deposition ◽

In Vitro Study ◽

Calcium Titanate ◽

Vitro Study ◽

Coating Method ◽

Osteoblast Adhesion ◽

Characterization Studies ◽

Orthopedic Applications

ABSTRACTDepending on the coating method utilized and subsequent heat treatments (such as through the use of plasma-spray deposition), inter-diffusion of atomic species across titanium (Ti) and hydroxyapatite (HA) coatings may result. These events may lead to structural and compositional changes that consequently cause unexpected HA phase transformations which may clearly influence the performance of an orthopedic implant. Thus, the objective of the present in vitro study was to compare the cytocompatibility properties of chemistries that may form at the Ti:HA interface, specifically HA, tricalcium phosphate (TCP), Ti doped HA, and those containing calcium titanate (CaTiO3). In doing so, results of this in vitro study showed that osteoblast adhesion increased with greater CaTiO3 substitutions in either HA or TCP. Specifically, osteoblast adhesion on HA and TCP composites with CaTiO3 was almost 4.5 times higher than over pure HA. Material characterization studies revealed that enhanced osteoblast adhesion on these compacts may be due to increasing shrinkage in the unit lattice parameters and consequent decrease in grain size. Although all CaTiO3 composites exhibited excellent osteoblast adhesion results, Ca9HPO4(PO4)5OH phase formation into TCP/CaTiO3 increased osteoblast adhesion the most; due to these reasons, these materials should be further studied for orthopedic applications.

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Recent Developments in Coatings for Orthopedic Metallic Implants

Coatings ◽

10.3390/coatings11070791 ◽

2021 ◽

Vol 11 (7) ◽

pp. 791

Author(s):

Muzamil Hussain ◽

Syed Hasan Askari Rizvi ◽

Naseem Abbas ◽

Uzair Sajjad ◽

Muhammad Rizwan Shad ◽

...

Keyword(s):

Stress Shielding ◽

Orthopedic Implant ◽

Coating Materials ◽

Implant Materials ◽

Metallic Implants ◽

Common Causes ◽

Recent Developments ◽

Orthopedic Applications ◽

The Impact ◽

Cocrmo Alloys

Titanium, stainless steel, and CoCrMo alloys are the most widely used biomaterials for orthopedic applications. The most common causes of orthopedic implant failure after implantation are infections, inflammatory response, least corrosion resistance, mismatch in elastic modulus, stress shielding, and excessive wear. To address the problems associated with implant materials, different modifications related to design, materials, and surface have been developed. Among the different methods, coating is an effective method to improve the performance of implant materials. In this article, a comprehensive review of recent studies has been carried out to summarize the impact of coating materials on metallic implants. The antibacterial characteristics, biodegradability, biocompatibility, corrosion behavior, and mechanical properties for performance evaluation are briefly summarized. Different effective coating techniques, coating materials, and additives have been summarized. The results are useful to produce the coating with optimized properties.

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Regulation of Osteoblast-Like Cell Behaviors on Hydroxyapatite by Electrical Polarization

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.361-363.1055 ◽

2007 ◽

Vol 361-363 ◽

pp. 1055-1058 ◽

Cited By ~ 6

Author(s):

Miho Nakamura ◽

Akiko Nagai ◽

Natalie Ohashi ◽

Yumi Tanaka ◽

Yasutaka Sekijima ◽

...

Keyword(s):

Cell Movement ◽

Stress Fiber ◽

Fiber Formation ◽

Wound Healing Assay ◽

Cell Behaviors ◽

Stress Fiber Formation ◽

Cytoskeleton Reorganization ◽

Osteoblast Adhesion ◽

As Stress

The osteoblast adhesion to the substrates are recognized to play a fundamental role in osteoconduction process. The purpose of this study was to evaluate the in vitro behavior of osteoblasts cultured on polarized hydroxyapatite (HA), having the enhanced osteobonding abilities. Osteoblast-like cells were seeded onto the polarized HA and investigated the adhesion and motility. The polarization had no effects on the percentage of the number of the spreaded cells against all the adhered cells, but had significant effects on the elongation of adhered cells from fluorescent observation and on the cell motility showed by the wound healing assay. The charges induced on the HA surface accelerated the cytoskeleton reorganization of the adhered cells cultured on HA specimens. The acceleration was emerged as the cells shape, actin filament pattern such as stress fiber formation, and the prolongation of the cell movement distances.

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Surface Wettability Enhances Osteoblast Adhesion on Silicon-Substituted Hydroxyapatite Thin Films

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.330-332.877 ◽

2007 ◽

Vol 330-332 ◽

pp. 877-880 ◽

Cited By ~ 6

Author(s):

E.S. Thian ◽

J. Huang ◽

Serena Best ◽

Zoe H. Barber ◽

William Bonfield

Keyword(s):

Thin Films ◽

Contact Angle ◽

Actin Filaments ◽

Culture Study ◽

Cell Culture Study ◽

Angle Measurements ◽

Contact Angle Measurements ◽

Osteoblast Adhesion ◽

Lower Contact

Crystalline hydroxyapatite (HA) and 0.8 wt.% silicon-substituted HA (SiHA) thin films were produced using magnetron co-sputtering. These films were subjected to contact angle measurements and in vitro cell culture study using human osteoblast-like (HOB) cells. A wettability study showed that SiHA has a lower contact angle, and thus is more hydrophilic in nature, as compared to HA. Consequently, enhanced cell growth was observed on SiHA at all time-points. Furthermore, distinct and well-developed actin filaments could be seen within HOB cells on SiHA. Thus, this work demonstrated that the surface properties of the coating may be modified by the substitution of Si into the HA structure.

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