Amorphous Magnesium Coating for Achieving Functional Changes from Antibacterial to Osteogenic Activities.

Medical devices composed of titanium (Ti) should exhibit antibacterial and osteogenic activities to achieve both infection prevention and rapid bone reconstruction. Here, a Ti surface was modified by performing magnetron sputtering (MS) using pure Mg or Mg-30Ca alloy targets for surface functionalization. MC0, prepared with a pure Mg target, had a crystalline metallic-Mg coating layer, whereas MC30, prepared with an Mg-30Ca alloy target, had an amorphous coating composed of Mg and Ca.

Calcium Citrate Amount and Gelatine Source Impact on Hydroxyapatite Formation in Bone Regeneration Material in Simulated Body Fluid.

Bone grafting is crucial for bone regeneration. Recent studies have proposed the use of calcium citrate (CC) as a potential graft material. Notably, citrate does not inhibit hydroxyapatite (HAp) formation at specific calcium-to-citrate molar ratios.

Silver phosphate-modified carbonate apatite honeycomb scaffolds for anti-infective and pigmentation-free bone tissue engineering.

Bone regeneration using synthetic materials has a high rate of surgical site infection, resulting in severe pain for patients and often requiring revision surgery. We propose AgPO-based surface modification and structural control of scaffolds for preventing infections in bone regeneration. We demonstrated the differences in toxicity and antibacterial activity between in vitro and in vivo studies and determined the optimal silver content in terms of overall anti-infection effects, bone regeneration, toxicity, and pigmentation.

Effects of pH on the microarchitecture of carbonate apatite granules fabricated through a dissolution-precipitation reaction.

Both the composition and architecture of artificial bone govern bone regeneration. Herein, carbonate apatite (CAp), which has a similar mineral composition to bone, was prepared by immersing calcium carbonate (CaCO) in a phosphate solution with varying acidification levels (pH 6.0) to pH 8.

Apatite-Forming Ability and Visible Light-Enhanced Antibacterial Activity of CuO-Supported TiO Formed on Titanium by Chemical and Thermal Treatments.

Titanium with apatite-forming ability as well as antibacterial activity is useful as a component of antibacterial dental implants. When Ti was subjected to hydrogen peroxide (HO), copper acetate (Cu(OAc)), and heat (HO-Cu(OAc)-heat) treatments, a network structure of anatase and rutile titanium dioxide (TiO) and fine copper oxide (CuO) particles was formed on the Ti surface. The resulting samples accumulated a dense and uniform apatite layer on the surface when incubated in simulated body fluid and showed enhanced antibacterial activity against and under visible-light irradiation.

Effects of multiple firings on the translucency, crystalline phase, and mechanical strength of highly translucent zirconia.

This study aimed to clarify the effects of multiple firings on the translucency, crystal structure, and mechanical strength of highly translucent zirconia. Four types of highly translucent zirconia (LAVA Esthetic, LAVA Plus, KATANA Zirconia STML, and KATANA Zirconia HTML) were fired three times at three different temperatures, and the translucency, crystal structure, and flexural strength were evaluated before and after firing. The translucency was statistically compared using repeated-measures analysis of variance; the zirconia phase composition was assessed using X-ray diffraction followed by Rietveld analysis; and the biaxial flexural strength was assessed using Weibull analysis.

Antibacterial and osteogenic thin films on Ti-6Al-4V surface formed by passivation process in copper hydroxide solution.

Implant-associated infections are threatening and devastating complications that lead to bone destruction and loss. As a smooth surface is suitable for inhibiting bacterial adhesion, endowing antibacterial activity to the Ti surface without any structural changes in the surface topography is an effective strategy for preventing infection. The thin film on the Ti-6Al-4 V surface was functionalized to endow antibacterial activity by immersion in a Cu(OH) solution.

Electrochemical Deposition of Copper on Bioactive Porous Titanium Dioxide Layer: Antibacterial and Pro-Osteogenic Activities.

Ti surfaces must exhibit antibacterial activity without cytotoxicity to promote bone reconstruction and prevent infection simultaneously. In this study, we employed a two-step electrochemical treatment process, namely, microarc oxidation (MAO) and cathodic electrochemical deposition (CED), to modify Ti surfaces. During the MAO step, a porous TiO (pTiO) layer with a surface roughness of approximately 2.

Formation of octacalcium phosphate with incorporated dicarboxylate ions containing disulfide bonds.

Octacalcium phosphate (OCP) is a layered compound capable of incorporating carboxylate ions within its interlayer structure. In this study, we successfully synthesised OCP with incorporated 3,3'-dithiodipropionate ions. Our finding is beneficial for the development of novel OCP-based materials with dynamic properties derived from disulfide bonds.

Development of bioinspired damage-tolerant calcium phosphate bulk materials.

Improving the damage tolerance and reliability of ceramic artificial bone materials, such as sintered bodies of hydroxyapatite (HAp), that remain for long periods of time is of utmost importance. However, the intrinsic brittleness and low damage tolerance of ceramics make this challenging. This paper reports the synthesis of highly damage tolerant calcium phosphate-based materials with a bioinspired design for novel artificial bones.

Proliferation and differentiation of MC3T3-E1 cells on polymethyl methacrylate cements containing FeO and TiO for hyperthermic treatment of metastatic bone tumors.

Polymethyl methacrylate (PMMA) bone cement is widely used to relieve pain caused by metastatic bone tumors. We previously found that PMMA bone cement containing 15 mass% or more of TiO showed good apatite-forming ability, and 25 mass% or more of FeO generated sufficient heat for hyperthermia under an alternating current (AC) magnetic field. In this study, the cytocompatibility of PMMA bone cement with FeO:TiO weight ratios of 25:15 (F25T15-3/2-42) and 30:15 (F30T15-3/2-42) was evaluated using osteoblastic cells (MC3T3-E1).

Ant-nest type porous scaffold with micro-struts consisting of carbonate apatite for promoting bone formation and scaffold resorption.

Scaffolds having appropriate mechanical strength and providing a proper microenvironment for osteogenesis are expected to be effective alternatives to autografts for bone regeneration. In this study, ant-nest type porous (ANP) scaffolds consisting of CO Ap were fabricated using calcium carbonate powder or slurry and two types of polyurethane foam through a dissolution-precipitation reaction. ANP-type, three-dimensional, interconnected porous CO Ap scaffolds were fabricated by burning out the struts of polyurethane foams embedded in CaCO , followed by compositional transformation from CaCO to CO Ap.

Visible-Light-Enhanced Antibacterial Activity of Silver and Copper Co-Doped Titania Formed on Titanium via Chemical and Thermal Treatments.

Dental implants made of titanium (Ti) are used in dentistry, but peri-implantitis is a serious associated problem. Antibacterial and osteoconductive Ti dental implants may decrease the risk of peri-implantitis. In this study, titania (TiO) co-doped with silver (Ag) at 2.

Synthesis of Octacalcium Phosphate Containing Glutarate Ions with a High Incorporation Fraction.

Octacalcium phosphate (OCP) has received considerable attention in the field of ceramic biomaterials as an advanced functional material. It exhibits a layered structure composed of apatitic and hydrated layers and can incorporate various dicarboxylate ions into the hydrated layer. Saturated dicarboxylic acids (HOOC(CH)COOH) with an odd number of methylene groups (-CH-) exhibit lower incorporation fractions than those with an even number of methylene groups, possibly owing to a compositional dependence on the synthetic method.

Structurally optimized honeycomb scaffolds with outstanding ability for vertical bone augmentation.

Introduction: Cases of intractable dental implant require vertical bone augmentation; however, the predicted bone height and volume are difficult to obtain. In vertical bone augmentation, the contact surface between the scaffold and the bone is limited to the bottom face of the scaffold. Furthermore, the strength decrease caused by scaffold resorption leads to collapse of the augmented site, leading to a decrease in the bone volume and height.

Fabrication and histological evaluation of ant-nest type porous carbonate apatite artificial bone using polyurethane foam as a porogen.

The composition of carbonate apatite (CO Ap) aids bone regeneration. Other features, such as porosity and pore interconnectivity of artificial bone, also govern bone regeneration. In general, a trade-off exists between the porosity and mechanical strength of artificial bone.

Surface functionalization with copper endows carbonate apatite honeycomb scaffold with antibacterial, proangiogenic, and pro-osteogenic activities.

Osteomyelitis is a potentially devastating inflammatory bone disease that leads to bone destruction and loss. Treatment of osteomyelitis requires the removal of residual bacteria as well as osteogenesis with angiogenesis at the site of treatment. Use of an appropriate amount of copper (Cu) in treatment scaffolds may achieve these goals without the risk of toxicity.

Octacalcium phosphate with incorporated carboxylate ions: a review.

Octacalcium phosphate (OCP) belongs to a family of calcium phosphate compounds. OCP has unique crystal-chemical properties; among calcium phosphate compounds, only OCP can incorporate carboxylate ions into its crystal lattice. An OCP with incorporated carboxylate ions is called an OCP carboxylate (OCPC).

Effects of pore interconnectivity on bone regeneration in carbonate apatite blocks.

Porous architecture in bone substitutes, notably the interconnectivity of pores, is a critical factor for bone ingrowth. However, controlling the pore interconnectivity while maintaining the microarchitecture has not yet been achieved using conventional methods, such as sintering. Herein, we fabricated a porous block using the crystal growth of calcium sulfate dihydrate, and controlled the pore interconnectivity by limiting the region of crystal growth.

Granular honeycomb scaffolds composed of carbonate apatite for simultaneous intra- and inter-granular osteogenesis and angiogenesis.

Granular porous calcium phosphate scaffolds are used for bone regeneration in dentistry. However, in conventional granules, the macropore interconnectivity is poor and has varying size. Herein, we developed a productive method for fabricating carbonate apatite honeycomb granules with uniformly sized macropores based on extrusion molding.

Fabrication and histological evaluation of porous carbonate apatite blocks using disodium hydrogen phosphate crystals as a porogen and phosphatization accelerator.

The porous architecture of artificial bones plays a pivotal role in bone ingrowth. Although salt leaching methods produce predictable porous architectures, their application in the low-temperature fabrication of ceramics remains a challenge. Carbonate apatite (CO Ap) blocks with three ranges of pore sizes: 100-200, 200-400, and 400-600 μm, were fabricated from CaCO blocks with embedded Na HPO crystals as a porogen and accelerator for CaCO -to-CO Ap conversion.

Antibacterial Honeycomb Scaffolds for Achieving Infection Prevention and Bone Regeneration.

Surgical site infection (SSI) is a severe complication associated with orthopedic bone reconstruction. For both infection prevention and bone regeneration, the framework surface of osteoconductive and bioresorbable scaffolds must be locally modified by minimum antibacterial substances, without sacrificing the osteoconductivity of the scaffold framework. In this study, we fabricated antibacterial honeycomb scaffolds by replacing carbonate apatite, which is the main component of the scaffold, with silver phosphate locally on the scaffold surface via dissolution-precipitation reactions.

No-Observed-Effect Level of Silver Phosphate in Carbonate Apatite Artificial Bone on Initial Bone Regeneration.

Fracture-related infections require both treatments for bacteria removal and bone reconstruction. The use of combined broad-spectrum antibacterial silver compounds and artificial bone with high osteogenic activity is considered to be an effective strategy for achieving these treatments in one surgery. However, silver compounds are toxic for living tissues even at low concentrations.

Enhancement of antibacterial property of titanium by two-step micro arc oxidation treatment.

A customized micro arc oxidation (MAO) treatment technique was developed to obtain desirable antibacterial properties on titanium surfaces. The two-step MAO treatment was applied to fabricate a specimen containing both Ag and Zn in its surface oxide layer. Surface analyses and metal-ion release tests were performed to evaluate the presence of Ag and Zn and the ion release behavior for simulating practical usage, respectively.

Antibacterial Property and Biocompatibility of Silver, Copper, and Zinc in Titanium Dioxide Layers Incorporated by One-Step Micro-Arc Oxidation: A Review.

Titanium (Ti) and its alloys are commonly used in medical devices. However, biomaterial-associated infections such as peri-implantitis and prosthetic joint infections are devastating and threatening complications for patients, dentists, and orthopedists and are easily developed on titanium surfaces. Therefore, this review focuses on the formation of biofilms on implant surfaces, which is the main cause of infections, and one-step micro-arc oxidation (MAO) as a coating technology that can be expected to prevent infections due to the implant.