Dicalcium Phosphate Anhydrous Research Articles

COMPARATIVE CHARACTERIZATION OF ARC-PVD ZrN AND PEO HYDROXYAPATITE COATINGS ON PURE Ti-6Al-4V SUBSTRATES FOR BIOMEDICAL APPLICATIONS

The nanocrystalline films of zirconium nitride have been synthesized using ion-plasma vacuum-arc deposition technique on pure Ti-6Al-4V, whereas the hydroxyapatite coatings were deposited by the method of plasmaelectrolytic oxidation in alkaline electrolytes (hydroxyapatite + 1 М potassium hydroxide). Structure evaluation by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) with microanalysis (EDS) – were performed to study phase and chemical composition, surface morphology, microstructure of coatings. The formed HA PEO coatings with spheroidal structure contain the phases of CaTiO3 calcium titanate, CaHPO4 anhydrous dicalcium phosphate, and Ca10(PO4)6(OH)2 hydroxyapatite. It was revealed that ZrN single-phase coatings of cubic modification with finecrystalline grains of 20 nm in size were formed. This experimental study found that coating Ti-6Al-4V with ZrN and HA positively influences preosteoblast cell adhesion, which results in the almost complete coverage of the surface, along with a less number of cells grown on uncoated titanium surface.

Preliminary comparison of the remineralization and desensitization effects of a novel mineralized ion-releasing toothpaste and commercially available competitive products

Background/purposeToothpaste plays an important role in brushing teeth to maintain oral hygiene and health. The purpose of this study was to develop a new toothpaste containing surface nanocrystal-rich dicalcium phosphate anhydrous (DCPA) powder and to investigate its effect on tooth samples. Materials and methodsThe innovative toothpaste (REALCaP®/Group R) was compared with two commercial toothpastes (BioRepair®/Group B and Sensodyne®/Group S). Brushing cycle tests were performed on bovine tooth slices coated with individual toothpaste and a control group without toothpaste (Group C). Microhardness, roughness, surface structure observation, and X-ray diffraction (XRD) were performed on cycle days 4, 7, and 14 to analyze the impact of the toothpastes on tooth samples. ReultsMicrohardness in the Group R was higher than that of the other groups regardless of the cycle days. Roughness in the Group R increased on days 4 and 7 but decreased on day 14. Roughness in the groups S and B increased with days. Microstructural observation revealed that most exposed dentinal tubules had been sealed in the Group R on day 14. Overlay thickness in the Group R was significantly higher than that in the groups S and B on days 4, 7, and 14. XRD analysis showed no hydroxyapatite (HA) peak in the Group S. The HA peak in the Group R was higher than that in the Group B on day 14. ConclusionThe innovative toothpaste has better properties than the commercially available products in terms of microhardness, roughness, and effectiveness in sealing dentinal tubules.

An innovative biomimetic porous bioceramic to facilitate bone tissue regeneration: microstructural characteristics, biocompatibility, and in vivo rabbit model evaluation

The present study aimed to develop a highly pure and crystalline beta-tricalcium phosphate (β-TCP) bone graft substitute using the propagated Scleractinian coral. The solid-state reaction followed by heat-treatment (1050 °C–1100 °C for 1 h) between calcium carbonate from the propagated coral and dicalcium phosphate anhydrous was performed to fabricate the coral-derived β-TCP. The microstructural, in vitro, and in vivo properties of the propagated coral and heat-treated specimens were characterized through scanning electron microscopy, X-ray diffractometry, Fourier transform infrared spectroscopy, Raman spectroscopy, cell viability assay, and rabbit model. Results confirmed that the pure coral-derived β-TCP with interconnected microporosity was successfully fabricated at a temperature of 1000 °C. The co-existence of β-TCP and hydroxyapatite (HAp) was formed at the higher temperatures of 1050 °C and 1100 °C. When the temperature increased from 1000 °C to 1100 °C, the morphologies and crystalline structures in the coral-derived specimens were changed from granule-like aragonite (orthorhombic) → spherical particle-like β-TCP (rhombohedral) → tetrahedron-like (β-TCP (rhombohedral) + HAp (hexagonal)) → hexagonal-like (β-TCP (rhombohedral) + HAp (hexagonal)). Cytotoxicity assay results indicated that the coral-derived β-TCP possessed favorable biocompatibility. Moreover, histological results also demonstrated that the coral-derived β-TCP exhibited proper resorbed properties and a significantly higher percentage in new formed bone tissue than the control β-TCP specimen at 26 weeks (∗p = 0.012). Thus, the coral-derived β-TCP with interconnected microporosity is a promising bone graft substitute that can be used for bone defect repair in dental and orthopedic fields.

Calcium Phosphate Bone Cements Incorporated with Black Phosphorus Nanosheets Enhanced Osteogenesis.

For decades, calcium phosphate bone cements (CPCs) showed impressive advantages for their good biocompatibility, injectability, and osteoconductivity in the bone repair field. However, it is still difficult to prepare CPCs with outstanding antibacterial and self-curing properties, sufficient phosphorus release, and osteoinductivity for clinical application. Herein, we used partially crystallized calcium phosphate and dicalcium phosphate anhydrate particles incorporated with black phosphorous nanosheets to prepare calcium phosphate bone cements (CPCs). The curing time, compressive strength, photothermal properties, and degradation performance of BP/CPC were investigated. In addition, the cytocompatibility and osteoinductivity of BP/CPC were evaluated by cell adhesion, cytotoxicity, alkaline phosphatase detection, alizarin red staining, and western blot assay. The results indicated that BP/CPC showed adjustable curing time, good cytocompatibility, outstanding photothermal properties, and osteoinductivity, suggesting their potential application for bone regeneration.

Synthesis and characterization of a calcium phosphate bone cement with quercetin-containing PEEK/PLGA microparticles

This study aimed to describe the synthesis and characterization of a calcium phosphate cement (CPC) with polyetheretherketone/poly (lactic-co-glycolic) acid (PEEK/PLGA) micro-particles containing quercetin. CPC powder was synthesized by mixing dicalcium phosphate anhydrate and tetracalcium phosphate. To synthesize PEEK/PLGA microparticles, PLGA85:15 was mixed with 90 wt% PEEK. The weight ratio of quercetin/PLGA/PEEK was 1:9:90 wt%. PEEK/PLGA/quercetin microparticles with 3, 5, and 6 wt% was added to CPC. The setting time, compressive strength, drug release profile, solubility, pH, and porosity of synthesized cement were evaluated. The morphology and physicochemical properties of particles was analyzed by scanning electron microscopy, Fourier-transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), and inductively coupled plasma. Cytotoxicity was assessed by the methyl thiazolyl tetrazolium assay using dental pulp stem cells. Expression of osteoblastic differentiation genes was evaluated by real-time polymerase chain reaction. Data were analyzed by one-way ANOVA and Tukey’s test (alpha = 0.05). The setting time of 3 wt% CPC was significantly longer than 5 and 6 wt% CPC (P < 0.001). The 6 wt% CPC had significantly higher compressive strength than other groups (P = 0.001). The release of quercetin from CPCs increased for 5 d, and then reached a plateau. XRD and FTIR confirmed the presence of hydroxyapatite in cement composition. Significantly higher expression of osteocalcin (OCN) and osteopontin (OPN) was noted in 3 wt% and 6 wt% CPCs. Addition of quercetin-containing PEEK/PLGA microparticles to CPC enhanced its compressive strength, decreased its setting time, enabled controlled drug release, and up-regulated OPN and OCN.

Influence of moisture content on die filling of pharmaceutical powders

Flow performance of pharmaceutical powders dictates various manufacturing processes, such as blending, filling and tableting, and is determined by not only material properties but also environmental conditions, such as relative humidity and temperature. In this study, the effect of moisture content on flow performance of two commonly used pharmaceutical excipients (mannitol and dicalcium phosphate anhydrous) during die filling was investigated. A rotary die filling system was employed and the die filling efficiency was assessed using the concept of critical filling velocity. Powder flowability was also characterised using a dynamic flow tester and a shear cell tester. It was found that, with increasing moisture content, the flow parameters, including the basic flow energy, the average pressure drop and the cohesion, increased first and then decreased from a maximum at 50% relative humidity (RH). For both mannitol and dicalcium phosphate anhydrous (DCPA), when the relative humidity is high (say >50%) and the cohesion due to the formation of liquid bridges dominates, the critical filling velocity increases as the moisture content increases. While at a low relative humidity (e.g. 15%), a strong electrostatic attraction between particles was observed, which has a significant impact on the flow properties and the die filling performance of the powders.

Carbonate Apatite Crystal Formation in Novel Endodontic Sealer

Bioceramics play a key role in endodontics, mostly in surgical endodontics and difficult cases of root canal treatment. Carbonate apatite (CO3Ap) is the natural composition of dental and bone. The endodontic sealer is used in the obturation phase of endodontic treatment, which requires sealing ability and bioactivity to promote osseous repair of teeth and alveolar bone. CO3Ap crystal formation is essential for endodontics sealer as a bioceramic sealer. This study aims to investigate the crystal characterization of CO3Ap through X-Ray diffraction (XRD) and scanning electron microscope (SEM). The bioceramics endodontic sealer comprises dicalcium phosphate anhydrous (DCPA), vaterite, and Ca(OH)2. The powder cement ratio divided into 60% DCPA : 30% vaterite: 10% Ca(OH)2. Powder cement was mixed with 0.2 mol/L Na2HPO4 added by 1% sodium carboxymethylcellulose and 32μg thymoquinone as an aqueous solution at the liquid to powder ratio of 0.6 and set at 37°C and 100% of relative humidity for 72h. XRD result showed that all precursor materials transformed into CO3Ap after 72h treatment. SEM image showed coral-like CO3Ap morphology that is characteristic of CO3Ap. The initial results of novel CO3Ap endodontic sealers show that crystal formation occurs and has potential to be used as an endodontic sealer.

Influence of the calcium orthophosphate:glass ratio and calcium orthophosphate functionalization on the degree of conversion and mechanical properties of resin-based composites.

The study verified the influence of calcium orthophosphate (CaP):glass ratio on the degree of conversion and mechanical properties of resin-based composites containing either TEGDMA-functionalized dicalcium phosphate anhydrous (DCPA) or non-functionalized DCPA particles. The null hypotheses were that the evaluated variables are not affected by (1) CaP:glass ratio or (2) DCPA functionalization. DCPA particles were synthesized and half of them were functionalized with TEGDMA. Particle characterization included x-ray diffraction, elemental analysis, laser scattering, helium picnometry and scanning electron microscopy. Two series of composites were prepared containing either DCPA-NF (non-functionalized) or DCPA-F (functionalized), with total inorganic content of 50 vol % and DCPA:silanized barium glass (BG) ratios from 10:40 to 50:0. A composite containing 50 vol % BG was tested as control. DC was determined using FTIR spectroscopy. Biaxial flexural strength and modulus were tested after 24 h in water. Data were analyzed using Kruskal-Wallis/Dunn (flexural properties) or analysis of variance/Tukey tests (DC). Materials with similar actual DCPA contents were compared using Student's t test (alpha: 0.05). DC was higher for materials with DCPA-F, except for the 10:40 ratio. DCPA-F resulted in higher strength than DCPA-NF only at 40:10 ratio. Modulus was not affected by functionalization. Materials with similar actual DCPA contents showed differences in DC (F > NF), while no difference in flexural properties was observed between materials with 28%-30% DCPA. Both null hypotheses were rejected.

Predictive evaluation of multicomponent direct compress model tablets by integrating sphere UV-Vis spectroscopy and chemometrics.

Control of the pharmaceutical manufacturing process and active pharmaceutical ingredients (API) is essential to product formulation and bioavailability. The aim of this study is to predict tablet surface API concentration by chemometrics using integrating sphere UV-Vis spectroscopy, a non-destructive and contact-free measurement method. Riboflavin, pyridoxine hydrochloride, dicalcium phosphate anhydrate, and magnesium stearate were mixed and ground with a mortar and pestle, and 100mg samples were subjected to direct compression at a compaction pressure of 6MPa at 7mm diameter. The flat surface tablets were then analyzed by integrating sphere UV-Vis spectrometry. Standard normal variate (SNV) normalization and principal component analysis were applied to evaluate the measured spectral dataset. The spectral ranges were prepared at 300-800nm and 500-700nm with SNV normalization. Partial least squares (PLS) regression models were constructed to predict the API concentrations based on two previous datasets. The regression vector of constructed PLS regression models for each API was evaluated. API concentration prediction depends on riboflavin absorbance at 550nm and the excipient dicalcium phosphate anhydrate. Integrating sphere UV-Vis spectrometry is a useful tool to process analytical technology.

Preparation of antimicrobial calcium phosphate/protamine composite powders with fluoride ions using octacalcium phosphate

Calcium phosphates are key biomaterials in dental treatment and bone regeneration. Biomaterials must exhibit antibacterial properties to prevent microbial infection in implantation frameworks. Previously, we developed various types of calcium phosphate powders (amorphous calcium phosphate, octacalcium phosphate (OCP), dicalcium phosphate anhydrate, and hydroxyapatite) with adsorbed protamine (which is a protein with antibacterial property) and confirmed their antibacterial property. In this study, as foundational research for the development of novel oral care materials, we synthesized calcium phosphate composite powders from three starting materials: i) OCP, which intercalates organic compounds, ii) protamine, which has antibacterial properties, and iii) F– ion, which promotes the formation of apatite crystals. Through investigating the preparation concentration of the F– ions and their loading into OCP, it was found that more F– ion could be loaded at higher concentrations regardless of the loading method. It was also observed that the higher the preparation concentration, the more the OCP converted to fluorapatite. The synthesized calcium phosphate composite powders were evaluated for biocompatibility through proliferation of MG-63 cells, with none of the powders exhibiting any growth inhibition. Antimicrobial tests showed that the calcium phosphate composite powders synthesized with protamine and F– ion by precipitation had enhanced antimicrobial properties than those synthesized by protamine adsorption. Thus, the calcium phosphate composite powder prepared from OCP, protamine, and F– ion forms the basis for promising antimicrobial biomaterials.Graphical abstract

Engineering 3D Printed Scaffolds with Tunable Hydroxyapatite.

Orthopedic and craniofacial surgical procedures require the reconstruction of bone defects caused by trauma, diseases, and tumor resection. Successful bone restoration entails the development and use of bone grafts with structural, functional, and biological features similar to native tissues. Herein, we developed three-dimensional (3D) printed fine-tuned hydroxyapatite (HA) biomimetic bone structures, which can be applied as grafts, by using calcium phosphate cement (CPC) bioink, which is composed of tetracalcium phosphate (TTCP), dicalcium phosphate anhydrous (DCPA), and a liquid [Polyvinyl butyral (PVB) dissolved in ethanol (EtOH)]. The ink was ejected through a high-resolution syringe nozzle (210 µm) at room temperature into three different concentrations (0.01, 0.1, and 0.5) mol/L of the aqueous sodium phosphate dibasic (Na2HPO4) bath that serves as a hardening accelerator for HA formation. Raman spectrometer, X-ray diffraction (XRD), and scanning electron microscopy (SEM) demonstrated the real-time HA formation in (0.01, 0.1, and 0.5) mol/L Na2HPO4 baths. Under those conditions, HA was formed at different amounts, which tuned the scaffolds’ mechanical properties, porosity, and osteoclast activity. Overall, this method may pave the way to engineer 3D bone scaffolds with controlled HA composition and pre-defined properties, which will enhance graft-host integration in various anatomic locations.

A new parameter for characterization of tablet friability based on a systematical study of five excipients

In this paper, a new parameter highly relevant to tablet friability is proposed based on a systematical study of the tablet quality attributes and texture performances of five different direct compression excipients, including microcrystalline cellulose, starch, lactose, mannitol, and dicalcium phosphate anhydrous. The new parameter, named Strain/Stress Max, could indicate the tablet’s ability against external force to maintain integrity. It was directly obtained from the diametrical breaking test which is extensively used to assess tablet mechanical strength, and thus no extra work is required. The values varied significantly among the tablets formed by materials with different mechanical properties under the same compression pressure. A design space was developed to achieve <1% tablet friability at various combinations of Strain/Stress Max and tensile strength. Additionally, data from binary mixture tablets validated the availability of the constructed design space. And the upper limit of Strain/Stress Max value was advisable for 1.5 MPa−1 for pharmaceutical tablets. In conclusion, the new parameter and design space are available for fast identification of the tablets with acceptable friability to facilitate the development of tablet formulation using as few active pharmaceutic ingredients as possible.

Biomimetic Ceramic Composite: Characterization, Cell Response, and In Vivo Biocompatibility.

The present study aimed to synthesize biphasic calcium phosphate ceramics (CaPs) composed of β-tricalcium phosphate (β-TCP) and hydroxyapatite (HAp) from the propagated Scleractinian coral and dicalcium phosphate anhydrous using a solid-state reaction followed by heat treatment at a temperature of 1100 °C for 1 h to 7 days. The as-prepared coral and coral-derived biphasic CaPs samples were characterized through scanning electron microscopy, X-ray diffractometry, Fourier transform infrared spectroscopy, and Raman spectroscopy. The cell response of the biphasic CaPs was evaluated by in vitro cytotoxicity assessment using mouse fibroblast (L929) cells. The bilateral femoral defect rabbit model was used to assess the early local reaction of the coral-derived biphasic CaPs bone graft on tissue. The results confirmed that the co-existence of β-TCP and HAp was formed at 1100 °C for 1 h. The ratio of HA/β-TCP increased as the heat-treatment time increased. The coral-derived biphasic CaPs comprising 61% HAp and 39% β-TCP (defined as HT-3) were not cytotoxic. Furthermore, no significant differences in local tissue reaction were observed between the HT-3 sample and autogenous bone. Therefore, the synthesized coral-derived biphasic CaPs is a candidate for bone grafting due to its good biocompatibility.

Effect of pH on the In Vitro Biocompatibility of Surfactant-Assisted Synthesis and Hydrothermal Precipitation of Rod-Shaped Nano-Hydroxyapatite.

Given their wide range of biomedical applications, hydroxyapatite (HA) nanoparticles are an attractive material widely used in many fields. Therefore, a simple, inexpensive, and stable process for the synthesis of HA nanoparticles is necessary to meet current needs. Herein, we studied HA synthesis assisted by four surfactants, namely cation, anion, non-ionic, and zwitterion templates, to verify the synthesis phase, aspect ratio, morphology, and biocompatibility under different environments (i.e., pH 4 and 9) before and after calcination. Results showed that before calcination, the surfactant-free groups could not produce HA but showed an abundant dicalcium phosphate anhydrous (DCPA) phase at pH 4. Except for the anionic group containing a small amount of DCPA, all surfactant-assistant groups presented single-phase HA in acidic and alkaline environments. The diameter of HA synthesized at pH 4 was significantly larger than that of HA synthesized at pH 9, and the effect of aspect ratio changes after calcination was more significant than that before calcination. The uncalcined rod-shaped HA synthesized with a non-ionic template at pH 4 demonstrated excellent cell viability, whereas anionic, cationic, and non-ionic surfactants exhibited biocompatibility only after calcination. At pH 9, non-ionic and uncalcined zwitterion-assisted rod-shaped HA showed excellent biocompatibility. In conclusion, the uncalcined HA rod-shaped nanoparticles synthesized from the non-ionic template at pH 4 and 9 and the zwitterion template at pH 9, as well as all surfactant-assisted HA after calcination, had no cytotoxicity. These tailor-made non-toxic HA types can meet the different requirements of apatite composite materials in biomedical applications.

Effects of Hinokitiol and Dicalcium Phosphate on the Osteoconduction and Antibacterial Activity of Gelatin-Hyaluronic Acid Crosslinked Hydrogel Membrane In Vitro.

Many hydrogel-based crosslinking membranes have been designed and tailored to meet the needs of different applications. The aim of this research is to design a bifunctional hydrogel membrane with antibacterial and osteoconducting properties to guide different tissues. The membrane uses gelatin and hyaluronic acid as the main structure, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride as the crosslinker, hinokitiol as the antibacterial agent, and dicalcium phosphate anhydrous (DCPA) micron particles for osteoconduction. Results show that the hydrogel membrane with added DCPA and impregnated hinokitiol has a fixation index higher than 88%. When only a small amount of DCPA is added, the tensile strength does not decrease significantly. The tensile strength decreases considerably when a large amount of modified DCPA is added. The stress–strain curve shows that the presence of a large amount of hinokitiol in hydrogel membranes results in considerably improved deformation and toughness properties. Each group impregnated with hinokitiol exhibits obvious antibacterial capabilities. Furthermore, the addition of DCPA and impregnation with hinokitiol does not exert cytotoxicity on cells in vitro, indicating that the designed amount of DCPA and hinokitiol in this study is appropriate. After a 14-day cell culture, the hydrogel membrane still maintains a good shape because the cells adhere and proliferate well, thus delaying degradation. In addition, the hydrogel containing a small amount of DCPA has the best cell mineralization effect. The developed hydrogel has a certain degree of flexibility, degradability, and bifunctionality and is superficial. It can be used in guided tissue regeneration in clinical surgery.

Investigation on structural properties and bioactivity of nanosized biphasic calcium phosphate

Synthetic biphasic bioceramics composed of hydroxyapatite (HA) and other calcium phosphates (CPs) can provide promising efficiency in the treatment of bone defects based on the rapid dissolution of the CPs, to allow its replacement by freshly formed bone, along with the slow resorption of the HA, to preserve the volume of the grafted area. For this purpose, the present study was conducted to prepare nanosized biphasic calcium phosphate (n-BCP) using a facile mechanochemical process. The experimental outputs were also compared to the commercial-grade HA in terms of physicochemical features. The Rietveld refinement was utilized to calculate the phase contents and crystal structures of the composites, including crystallite size, lattice parameters, and unit cell volume. Besides, the atomic arrangement of Ca1, Ca2, PO43−, and OH− groups in the hexagonal crystal structure of HA and triclinic structure of anhydrous dicalcium phosphate (DCPA) was determined. The phase fraction, crystallite size, and the powder density of the biphasic structures, which were derived by Rietveld refinement, were found to be affected by ball-milling. In addition to biphasic structures, a monolithic hexagonal HA with an isotropic crystal growth was formed after 7 h of ball-milling under an argon atmosphere. The in vitro test in a simulated body fluid (SBF) confirmed the bioactivity of the biphasic structure through the formation of a bone-like apatite layer after one week.

Modification of natural hydrocolloid as disintegrant in aceclofenac tablet formulation

The purpose of present exploration was to modify kappa (k)-Carrageenan, by crosslinking, and assessed it as a tablet disintegrant to strengthen the solubility of the drug (aceclofenac) in tablet formulation. Modified k-Carrageenan was synthesized by reacting it with epichlorhydrin at heterogenous conditions. The swelling action of the product was investigated in order to optimize reaction circumstances for chemical cross-linking. Best modified k-Carrageenan procured by optimizing the reaction conditions and it was characterized for swelling index, particle size distribution, solubility, viscosity, gel strength and Fourier transform infrared spectroscopy (FTIR). Influence of modified k-Carrageenan on dissolution profile of therapeutic was also investigated along with other evaluation parameters. Modified k-Carrageenan exhibiting significant swelling index which is comparable to that of superdisintegrants. On comparative investigation as a tablet disintegrant by preparing anhydrous dicalcium phosphate tablet, modified k-Carrageenan showed disintegration time less than 20 seconds. Dissolution of aceclofenac (Class II) tablet formulaion utilizing modified k-Carrageenan was comparable with commercially available superdisintegrants. Faster dissolution of the accommodated drug was achieved with modified k-Carrageenan which was comparable with dissolution of the tablet formulation containing other superdisintegrants. The competent concentration of k-Carrageenan was found to be 5-15% as tablet disintegrant. Modified k-Carrageenan might be encouraging tablet disintegrant in fast dissolving formulations and can be worn in direct compression method. Keywords: k-Carageenan. Epichlorhydrin. Aceclofenac. Crosslinking. Superdisintegrant

Influence of adding Pluronic F127 in the electrolyte on the morphology, structure and biofilm adhesion of calcium phosphate coatings

In this work, we have investigated the addition of Pluronic F127 (PF127) into the electrolyte solution on the structure, morphology and antibacterial growth of calcium phosphate (CaP) coatings synthesized by an electrochemical method on Ti substrate. Different parameters of the deposition process were investigated, which were temperature, time and PF127 wt%. The coatings were characterized by X-ray diffraction (XRD), gravimetric analysis, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In vitro antimicrobial assays against S. aureus were performed. XRD analysis confirmed the formation of dicalcium phosphate dihydrate (DCPD) or anhydrous dicalcium phosphate (DCPA) and octacalcium phosphate (OCP). The structure and morphology depended mainly on PF127 wt% and deposition temperature in lower deposition time. Interestingly, structure and morphology were not influenced by adding PF127 at higher deposition time using higher PF127 concentrations. The morphology by SEM changed from plate-like to fiber by varying the PF127 concentration as well as blocks at higher temperatures. Moreover, all coatings were crystalline, uniform and crack-free. Antibacterial assays showed that biofilm formation was prevented when a coating of PF127 is deposited on the surface. Bacterial growth depended on the phase and morphology of washed coatings. Thus, the structure, morphology and consequently bacterial growth resistance can be tailored by the use of PF127 in the electrochemical processing at shorter deposition times.

Injectable calcium phosphate and styrene–butadiene polymer-based root canal filling material

AbstractBackgroundThree-dimensional obturation of the root canal system is mandatory for a successful root canal treatment. Using a filling material with optimal properties may enable the root canal to be sealed well and therefore obtain the desired obturation.ObjectiveTo develop a new injectable paste endodontic filling material using calcium phosphate powder and a styrene–butadiene emulsion polymer.MethodsThe powder phase comprised an equivalent molar ratio of tetracalcium phosphate, anhydrous dicalcium phosphate, bismuth oxide, and calcium chloride. The liquid phase comprised a styrene–butadiene rubber emulsion in distilled water. The powder and the liquid were mixed to achieve a paste consistency. The paste was subjected to various tests including flow, setting time, dimensional change, solubility, and radiopacity to indicate its suitability as a root canal filling material. All these tests were conducted according to the American National Standards Institute–American Dental Association for endodontic sealing materials. After passing these tests, the paste was submitted to an injectability test.ResultsThe material showed acceptable flowability with 19.1 ± 1.3 min setting time and 0.61 ± 0.16% shrinkage after 30 days of storage. We found the highest solubility at 24 h (6.62 ± 0.58%), then the solubility decreased to 1.09 ± 0.08% within 3 days. The material was more radiopaque than a 3 mm step on an aluminum wedge. Furthermore, the material showed good injectability of 93.67 ± 1.80%.ConclusionsThe calcium phosphate powder in styrene–butadiene emulsion met basic requirements for a root canal filling material with promising properties.

Injectable calcium phosphate and styrene-butadiene polymer-based root canal filling material.

Three-dimensional obturation of the root canal system is mandatory for a successful root canal treatment. Using a filling material with optimal properties may enable the root canal to be sealed well and therefore obtain the desired obturation. To develop a new injectable paste endodontic filling material using calcium phosphate powder and a styrene-butadiene emulsion polymer. The powder phase comprised an equivalent molar ratio of tetracalcium phosphate, anhydrous dicalcium phosphate, bismuth oxide, and calcium chloride. The liquid phase comprised a styrene-butadiene rubber emulsion in distilled water. The powder and the liquid were mixed to achieve a paste consistency. The paste was subjected to various tests including flow, setting time, dimensional change, solubility, and radiopacity to indicate its suitability as a root canal filling material. All these tests were conducted according to the American National Standards Institute-American Dental Association for endodontic sealing materials. After passing these tests, the paste was submitted to an injectability test. The material showed acceptable flowability with 19.1 ± 1.3 min setting time and 0.61 ± 0.16% shrinkage after 30 days of storage. We found the highest solubility at 24 h (6.62 ± 0.58%), then the solubility decreased to 1.09 ± 0.08% within 3 days. The material was more radiopaque than a 3 mm step on an aluminum wedge. Furthermore, the material showed good injectability of 93.67 ± 1.80%. The calcium phosphate powder in styrene-butadiene emulsion met basic requirements for a root canal filling material with promising properties.