Enabling High-Performance Pressure and Proximity Dual-Mode Sensing with EGaIn/Ag/ZnO Egg-Shell Ternary Composite Particles.

Eutectic gallium-indium alloy (EGaIn) is a biocompatible liquid metal, promising for wearable electronics. Through functionalization and formation of composites, EGaIn-based materials have shown potential in multifunctional sensing devices. Here, egg-shell EGaIn/Ag/ZnO ternary composite particles were prepared through an ultrasound-assisted displacement reaction combined with room-temperature hydrolysis. The composite was further constructed as a wearable sensor capable of both pressure and proximity detection. For pressure sensing, due to the decrease in the Young's modulus of the egg-shell structure and the presence of the electrical double layers between Ag and ZnO, which enriched surface charges, the sensor showed excellent sensitivity at low pressures (2.17 KPa-1, <0.4 KPa) and thus the ability to sense body movements. For proximity sensing, the composite sensor was able to detect approaching objects that were up to 20 cm away. By combining and fitting the sensing curves for both the touchless and touching modes, the extracted parameters were used to create fingerprints for different objects, demonstrating the great potential of our sensor in the differentiation and identification of unknown objects for future robotics and artificial intelligence.

[Summary of 61 cases of removable denture restoration in children with congenital tooth deficiency].

PURPOSE: To explore the methods and characteristics of removable denture restoration in children with congenital missing teeth. METHODS: From 1998 to 2018, 61 children aging 3 to 12 years old with congenital dental deficiency were treated with removable dentures. There were 59 males and 2 females. Removable denture prostheses were designed according to the characteristics of the children and the residual teeth in the mouth. There were 42 complete dentures in 21 cases, 40 single jaw complete dentures and maxillary removable partial dentures in 20 cases and 40 removable partial dentures in upper and lower jaw, totally 61 cases and 122 dentures. RESULTS: After wearing the removable denture, the appearance, chewing and pronunciation of the children were improved significantly. CONCLUSIONS: Although the etiology of congenital tooth defect is not completely clear, children can have early denture restoration. It solves the difficulty of eating, improves appearance and pronunciation, and promotes growth and physical and mental health of children.

Multiple methods for the identification of heavy metal sources in cropland soils from a resource-based region.

Examination of heavy metal sources in soils from a resource-based region is essential for source identification and implementation of restoration strategies regarding soil contamination. A total of 1069 samples were collected from cropland soils in the Baiyin District (Loess Plateau, Northwest China), a characteristically resource-based region to investigate the sources of arsenic (As), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), vanadium (V), and zinc (Zn). Source identification was analyzed by multiple methods including spatial deviation (SD), correlation analysis (CA), enrichment factor (EF), principal component analysis (PCA), geographic information system (GIS), and positive matrix factorization (PMF). The results showed the combined applications of PMF, GIS, and PCA were accurate, pragmatic, and effective for source apportionment. Three origins were identified and the contribution rates were calculated as follows: approximately 95% of As came from wastewater irrigation; 75, 88, 60, and 76% of Cr, Mn, Ni, and V were separately derived from natural origins; and 81, 93, and 70% of Cu, Pb, and Zn originated from industrial sources, respectively. Natural origins, industrial sources, and wastewater irrigation were the three main contributors of heavy metals to cropland soils in this region.

Evaluation of Mechanical Properties and Marginal Fit of Crowns Fabricated Using Commercially Pure Titanium and FUS-Invest.

This study investigated the mechanical properties and single crown accuracy of the tailor-made Fourth University Stomatology investment (FUS-invest) for casting titanium. Background. Current investment for casting titanium is not optimal for obtaining high-quality castings, and the commercially available titanium investment is costly. Methods. Titanium specimens were cast using the tailor-made FUS-invest. The mechanical properties were tested using a universal testing machine. Fractured castings were characterized by energy-dispersive spectroscopy. 19 titanium crowns were produced using FUS-invest and another 19 by Symbion. The accuracy of crowns was evaluated. Results. The mechanical properties of the titanium cast by FUS-invest were elastic modulus 125.6 ± 8.8 GPa, yield strength 567.5 ± 11.1 MPa, tensile strength 671.2 ± 15.6 MPa, and elongation 4.6 ± 0.2%. For marginal fit, no significant difference (P > 0.05) was found at four marker points of each group. For internal fit, no significant difference (P > 0.05) was found between two groups, whereas significant difference (P < 0.01) was found at different mark point of each group. Conclusions. The mechanical properties of titanium casted using FUS-invest fulfilled the ISO 9693 criteria. The marginal and internal fit of the titanium crowns using either the FUS-invest or Symbion were similar.

[Research on physical and mechanical properties, crown accuracy by using self- made FUS-invest dental investment].

PURPOSE: To evaluate the physical and mechanical properties of pure titanium castings cast by self- made FUS-invest dental investment, and evaluate casting accuracy. METHODS: Seven pure titanium castings were cast by self-made FUS-invest zirconium investment and analyzed using servo hydraulic dynamic experiment system (JJG139-83 standard), scanning electron microscope and energy spectrum analysis. Thirty-eight crowns of pure titanium were cast by two different methods. One cast by FUS-invest zirconium embedding material was used for experiment and the other cast by phosphate embedding material was used as control. Casting accuracy was assessed through measuring the difference value d at the marginal marker points and distance between casting pieces of wall and working modes of casting were examined under microscope. Scanning electron microscope with energy-dispersive spectrum (EDS) was used to analyze the status of composition of the casting surface. SPSS 17.0 software package was used to investigate the difference of two groups. RESULTS: ①Qualitative analysis of servo hydraulic dynamic experiment system showed various mechanical properties: elastic modulus (123.5±14.2) GPa, yield strength (569.3±16.5) MPa, tensile strength (668.4±16.1) MPa, elongation (4.5±0.2)%. EDS analysis of the fracture was observed at different depth (13, 25, 50, 350 µm) under the surface of pollution layer, a little Si and Fe with different atomic percentage was found but no Zr. ②No significant difference (P>0.05) was found between each group of four markers on the marginal fit, and internal fit, whereas significant difference (P<0.01) was found at different marker point. CONCLUSIONS: The mechanical properties of commercially pure titanium casting by self-made FUS-invest zirconium-based investment can meet the qualification of dental metal materials, although elongation was a little lower. Both the marginal adaptation and internal fit between the two groups had no significant difference. The mean marginal difference was 46 µm, the mean internal difference at axial angle was 56 µm and approximately 0 at axial wall.

Effect of plasma nitriding and titanium nitride coating on the corrosion resistance of titanium.

STATEMENT OF PROBLEM: The passive film on the surface of titanium can be destroyed by immersion in a fluoridated acidic medium. Coating with titanium nitride (TiN) may improve the corrosion resistance of titanium. PURPOSE: The purpose of this in vitro study was to investigate the effect of duplex treatment with plasma nitriding and TiN coating on the corrosion resistance of cast titanium. MATERIAL AND METHODS: Cast titanium was treated with plasma nitriding and TiN coating. The corrosion resistance of the duplex-treated titanium in fluoride-containing artificial saliva was then investigated through electrochemical and immersion tests. The corroded surface was characterized by scanning electron microscopy (SEM) with energy-dispersive spectroscopy surface scan analysis. The data were analyzed using ANOVA (α=.05) RESULTS: Duplex treatment generated a dense and uniform TiN film with a thickness of 4.5 µm. Compared with untreated titanium, the duplex-treated titanium displayed higher corrosion potential (Ecorr) values (P<.001) and lower corrosion current density (Icorr) values (P<.001). SEM results showed that the surface of untreated titanium was more heavily corroded than that of duplex-treated titanium. Surface scan analysis of duplex-treated titanium that had been immersed in artificial saliva containing 2 g/L fluoride revealed fluorine on the titanium surface, whereas fluorine was not observed on the surface of untreated titanium after immersion in fluoride-containing artificial saliva. The concentration of titanium ions released from the treated titanium was less than the amount released from untreated titanium (P<.001). CONCLUSIONS: Duplex treatment by plasma nitriding and TiN coating significantly improved the corrosion resistance of cast titanium in a fluoride-containing environment.

The effects of pulsed electromagnetic field on the functions of osteoblasts on implant surfaces with different topographies.

The use of pulsed electromagnetic fields (PEMFs) is a promising approach to promote osteogenesis. However, few studies have reported the effects of this technique on the osseointegration of endosseous implants, especially with regard to different implant topographies. We focused on how the initial interaction between cells and the titanium surface is enhanced by a PEMF and the possible regulatory mechanisms in this study. Rat osteoblasts were cultured on three types of titanium surfaces (Flat, Micro and Nano) under PEMF stimulation or control conditions. Protein adsorption was significantly increased by the PEMF. The number of osteoblasts attached to the surfaces in the PEMF group was substantially greater than that in the control group after 1.5h incubation. PEMF stimulation oriented the osteoblasts perpendicular to the electromagnetic field lines and increased the number of microfilaments and pseudopodia formed by the osteoblasts. The cell proliferation on the implant surfaces was significantly promoted by the PEMF. Significantly increased extracellular matrix mineralization nodules were observed under PEMF stimulation. The expression of osteogenesis-related genes, including BMP-2, OCN, Col-1,ALP, Runx2 and OSX, were up-regulated on all the surfaces by PEMF stimulation. Our findings suggest that PEMFs enhance the osteoblast compatibility on titanium surfaces but to different extents with regard to implant surface topographies. The use of PEMFs might be a potential adjuvant treatment for improving the osseointegration process.

[Common errors and mistakes seen in Chinese prosthodontic articles].

As an editor of dental journals, the author found that some inappropriate writing and mistakes existed in many articles, which reduced the quality of the published papers. The problems can be divided into three categories: irregular terminology; not concise, inaccurate description; improper use of punctuation and title code. They were illustrated respectively in this article for readers to avoid these mistakes in the future.

Effects of polishing methods on Candida albicans adhesion on cast pure titanium surfaces.

OBJECTIVE: To explore the effects of different polishing methods on Candida albicans adhesion to cast pure titanium surfaces. METHODS: Pure titanium test specimens randomly divided into 4 groups: not specially treated (CT), manual polishing (MPT), electrolytic polishing (EPT), and centrifugal barrel polishing (CPT). Surface roughness was measured with surface profilometer. Contact angles of water, diiodomethane, and ethylene glycol on specimen surface were measured, and the free energy was calculated. Each group were immersed in a C. albicans suspension for 48 hours, and cell count of C. albicans adhesion were taken. Morphology of C. albicans adhesion was observed by SEM. RESULTS: Surface roughness (Ra) were in the following order: CT > EPT > MPT > CPT. The amount of C. albicans adhesion to the surface of CPT was significantly less than CT, MPT, and EPT by cells count (P < 0.05). In SEM, less C. albicans aggregation formed on the surface of CPT than other 3 groups. CONCLUSIONS: Specimens treated by the CPT method showed superior effect to the specimens treated with MPT and EPT methods in reducing the adhesion of C. albicans.

The effect of different titanium nitride coatings on the adhesion of Candida albicans to titanium.

OBJECTIVES: The aim of the present study was an in vitro evaluation of the effects of different titanium nitride (TiNx) coatings on Candida albicans (C. albicans) adhesion to titanium and to correlate these findings to differences in specific surface characteristics (surface topography, roughness, chemical component, and surface free energy). METHODS: TiNx coatings were prepared by physical vapour deposition (PVD), a plasma nitriding process or a dual nitriding process. Surface properties were analysed by the optical stereoscopic microscopy, scanning electron microscopy, roughmeter, and drop shape methods. Quantity comparisons of C. albicans on the four surfaces were assessed by cell count and XTT reduction assays. Types of adhesive C. albicans were explored by SEM and confocal laser scanning microscope. RESULTS: The nitrided modifications were found to influence the surface properties and fungal susceptivity of flat titanium. Compared to flat titanium, fewer adhered C. albicans in yeast form were observed on the TiN-coated surface, whereas the plasma nitrided surface did not show any reduced potential to adhere C. albicans in hyphal or yeast form. The dual nitrided coating showed anti-fungal characteristics, although a small quantity of hyphae were identified. Our findings indicate that the Ti2N phase is prone to C. albicans hyphae, while the TiN phase inhibits their adhesion. CONCLUSIONS: Different TiNx phases could influence the characteristics of C. albicans adhesion. TiN coating by PVD could be a potential modification to inhibit C. albicans.

[Effects of different tillage and fertilization modes on the soil physical and chemical properties and crop yield under winter wheat/spring corn rotation on dryland of east Gansu, Northwest China].

Based on the 7-year field experiment on the dryland of east Gansu of Northwest China in 2005-2011, this paper analyzed the variations of soil moisture content, bulk density, and nutrients content at harvest time of winter wheat and of the grain yield under no-tillage and conventional tillage and five fertilization modes, and approached the effects of different tillage and fertilization modes on the soil water storage and conservation, soil fertility, and grain yield under winter wheat/ spring corn rotation. In 2011, the soil moisture content in 0-200 cm layer and the soil bulk density and soil organic matter and available nitrogen and phosphorus contents in 0-20 cm and 20-40 cm layers under different fertilization modes were higher under no-tillage than under conventional tillage. Under the same tillage modes, the contents of soil organic matter and available nitrogen and available phosphorus were higher under the combined application of organic and inorganic fertilizers, as compared with other fertilization modes. The soil available potassium content under different tillage and fertilization modes decreased with years. The grain yield under conventional tillage was higher than that under no-tillage. Under the same tillage modes, the grain yield was the highest under the combined application of organic and inorganic fertilizers, and the lowest under no fertilization. In sum, no-tillage had the superiority than conventional tillage in improving the soil water storage and conservation and soil fertility, and the combined application of organic and inorganic fertilizers under conventional tillage could obtain the best grain yield.

Effect of a magnetron-sputtered ZrSiN/ZrO2 film on the bond strength of commercially pure titanium to porcelain.

STATEMENT OF PROBLEM: The excessively thick and nonadherent titanium oxide layer formed during the porcelain sintering process can cause bonding problems between titanium and porcelain. PURPOSE: The purpose of this study was to evaluate the effect of a magnetron-sputtered ZrSiN/ZrO2 composite film on the bond strength of commercially pure titanium (CP Ti) to porcelain. MATERIAL AND METHODS: Sixty-eight cast titanium specimens were prepared according to the ISO 9693 standard and then divided into 2 coated and 2 noncoated groups (n=17). The ZrSiN/ZrO2 composite film was deposited on specimens of the 2 coated groups by magnetron sputtering. A low-fusing porcelain was applied on 1 coated group and 1 noncoated group. A surface profilometer, surface roughness tester, energy-dispersive X-ray analysis (EDS), scanning electron microscopy (SEM), and x-ray diffraction (XRD) were used to examine the characteristics of the film and the interfacial properties, while the bond strength of titanium-porcelain specimens was analyzed with the 3-point bend test. The results were analyzed with an independent samples t test (α=.05). RESULTS: The mean bond strength of ZrSiN/ZrO2-coated CP Ti to porcelain (43.67 ±2.08 MPa) was significantly higher than that of the noncoated group (35.44 ±3.56 MPa). A generally cohesive failure mode was observed in the coated group, but the failure mode in the noncoated group was adhesive. EDS data showed that the ZrSiN/ZrO2 film effectively prevented the intrusion of oxygen into the Ti substrate. CONCLUSIONS: The data suggested that the magnetron-sputtered ZrSiN/ZrO2 film could significantly improve the bond strength of CP Ti to porcelain and this may have clinical significance.

[Corrosion resistance of casted titanium by compound treatments in the artificial saliva with different fluoride concentrations].

OBJECTIVE: To study the corrosion resistance of casted titanium by plasma nitriding and TiN-coated compound treatments in the artificial saliva with different fluoride concentrations and to investigate whether compound treatments can increase the corrosion resistance of casted titanium. METHODS: Potentiodynamic polarization technique was used to depict polarization curve and to measured the current density of corrosion (Icorr) and the electric potential of corrosion (Ecorr) of casted titanium (Group A) and casted titanium by compound treatments (Group B) in the artificial saliva with different fluoride concentrations. After electrochemical experiment, the microstructure was observed by scanning electron microscope (SEM). RESULTS: The Icorrs of Group A and B in the artificial saliva of different fluoride concentrations were (1530.23 ± 340.12), (2290.36 ± 320.10), (4130.52 ± 230.17) nA and (2.62 ± 0.64), (7.37 ± 3.59), (10.76 ± 6.05) nA, respectively. The Ecorrs were (-0.93 ± 0.10), (-0.89 ± 0.21), (-0.57 ± 0.09) V and (-0.21 ± 0.04), (-0.17 ± 0.03), (-0.22 ± 0.03) V, respectively.The Icorrs of Group B were significantly lower (P < 0.01)than that of Group A. The Icorrs increased significantly with the increasing of fluoride concentrations (P < 0.01). The Ecorrs of Group B were significantly higher than that of Group A (P < 0.01). The SEM confirmed the microstructure in the casted titanium was much severely than that in Group B, the microstructure in Group A and B corroded more and more heavily with increasing of fluoride concentrations. CONCLUSIONS: The increase of fluoride concentrations influence the corrosion resistance of both treated and untreated casted titanium negatively, but plasma nitriding and TiN-coated compound treatments can significantly increase the corrosion resistance of casted titanium.

[Experimental study on the bonding strength between FCVA film and titanium].

PURPOSE: To study the bonding strength between the FCVA (filtered cathode vacuum arc) film and the titanium substrate. METHODS: According to the Engineer Manual of Germany (VDI3198), the indentation test was applied to evaluate the bonding strength between the FCVA film and the titanium substrate. The structure of the FCVA film and the interface between the film and the substrate were observed by means of scanning electron microscope(SEM). RESULTS: The fracture pattern of the film was classified as HF3 at the load of 400N, the bonding strength was enough between the FCVA film and the titanium substrate. SEM photograph showed the thickness of the FCVA film was about 1.2µm equably and the film bonded to the substrate well. CONCLSION: The bonding strength between the FCVA film and the titanium substrate was enough to meet clinical demand.

Preparation and characterization of a titanium bonding porcelain.

The titanium bonding porcelain was synthesized through normal melting-derived route using borate-silicate system. The porcelain was characterized by thermal expansion, X-ray diffraction, scanning electron microscope and cytotoxicity tests. The results of X-ray diffraction showed that the main phase of the bonding porcelain was SnO2. The SnO2 microcrystals precipitated from the glass matrix when the SnO2 content was increased. The thermal expansion coefficient of bonding porcelains decreased with the increasing concentration of SiO2. The thermal expansion coefficient of bonding porcelains first decreased slightly with the increasing of B2O3 concentration (from 0 wt% to 10 wt%) and then increased to about 9.4×10(-6)/°C(from 10 wt% to 12 wt%). As an intermediate, B2O3 can act as both network formers and modifiers, depending on the relationship between the concentration of basic oxides and intermediates. The Vickers hardness of bonding porcelains increased with the increase of SnO2 concentration. When SnO2 concentration was 6 wt%, only Si and Sn elements attended the reaction between titanium and porcelain and mainly adhesive fracture was found at Ti-porcelain interface. When SnO2 concentration was 12 wt%, failure of the titanium-porcelain predominantly occurred in the bonding porcelain and mainly cohesive fracture was found at Ti-porcelain interface. The methyl thiazolyl tetrazolium assay results demonstrated that the cytotoxicity of the titanium porcelain was ranked as 0.

Influence of particle size distribution of dental opacifier on the color of titanium opaque porcelain.

OBJECTIVE: To investigate the effect of particle size distribution of opacifier tin dioxides (SnO(2)) on the color of dental opaque porcelain for pure titanium by spectrophotometer. METHODS: Sixteen groups of opaque porcelain powders were prepared by combining four grain size SnO(2) with four pigments (no pigment, yellow, coral pink and grey). Five porcelain discs (13 mm diameter and 2mm thickness) for each powder were fired. K/S ratios and L*a*b* values of specimens were obtained by a spectrophotometer. The maximum color differences (ΔE(max)) caused by grain size of SnO(2) in each pigment group were determined using the CIELAB and the CIEDE2000 formulas. The L*a*b* values in each pigment group were compared by MANOVA and the ΔE(max) of different pigment groups were subjected to one way ANOVA. RESULTS: With SnO(2) grain size increasing, the L* values decreased, and both a* and b* became more chromatic consistently in each pigment group (p<0.001). The ΔE(max) in all pigmented groups were above the 50:50% perceptibility thresholds, with ΔE(max) in yellow group greater than the acceptability thresholds. Significant difference was found in the ΔE(max) of four pigment groups regardless of the color formula (p<0.001). CONCLUSIONS: 15 wt% SnO(2) with median particle size ranging from 0.85 µm to 20.75 µm caused significantly perceptible color differences in the pigmented titanium opaque porcelains used in this study.

[Effect of investment composition ratio for pure titanium crown and bridge on some mechanical properties of mould].

OBJECTIVE: To determine the optimal composition of a self-developing investment material by measuring physical and mechanical properties of mould. METHODS: L(9) (3(4)) orthogonal design was adopted. One hundred and fifty specimens with the size of 80 mm × 20 mm × 20 mm were prepared to measure the atmospheric temperature bending strength, high temperature bending strength and residual bending strength. Nine specimens with the size of 5 mm diameter 25 mm heigh were prepared to survey the thermal expansion curve from ambient temperature to 1150°C. RESULTS: Strengths were greatly affected by fine powder proportion in refractory and water/powder ratio. When the content of fine powder was 35% and water/powder ratio was 1:7.5, adequate atmospheric temperature strength and high temperature strength could be achieved. Moreover, the residual strength was moderate. The thermal extension curves of specimens in experiment group were almost similar. And the average linear expansion coefficient was (4 ∼ 5) × 10(-6)/°C. CONCLUSIONS: The three kinds of bending strength of self-developing investment material are compared with commercialized investment material for titanium casting when water/powder ratio and the content of fine powder are carefully controlled.

[Research progress on the treatment of obstructive sleep apnea and hypopnea syndrome with mandibular advancement device].

Obstructive sleep apnea and hypopnea syndrome (OSAHS) is characterized by obstruction of upper airway and respiratory disturbance, excessive daytime sleepiness and tiredness.The possible causes are obesity, hypertension, and upper airway malformations,etc. The location and degree of upper airway structure narrowing in patients have been investigated in many ways, such as X-ray, multi-slices spiral computed tomography, etc. With multi-planar reconstruction technique,3-dimensional construction of upper airway can be established which shows the delicate changes of the upper airway structure. Mandibular advancement device is known as an effective treatment on mild and moderate OSAHS. By advancing the mandible forward, it can increase the space of upper airway, especially the oropharyngeal space. This paper reviewed the methods of investigating on OSAHS and the change of upper airway structure in OSAHS patients treated with mandibular advancement device. Supported by Combined Research Fund of Bureau of Health, Yunan Province and Kunming Medical College(Grant No.2009CD205).

[Effects of nitrogen fertilization on wheat leaf photosynthesis under elevated atmospheric CO2 concentration].

In this paper, the effects of nitrogen (N) fertilization on the wheat leaf photosynthesis under long-term elevated atmospheric CO2 concentration (760 micromol x mol(-1)) was studied, based on the measurements of photosynthetic gas exchange parameters and light intensity-photosynthetic rate response curves at jointing stage. Under the long-term elevated atmospheric CO2 concentration, applying sufficient N could increase the wheat leaf photosynthetic rate (Pn), transpiration rate (Tr), and instantaneous water use efficiency (WUEi). Comparing with those under ambient atmospheric CO2 concentration, the Po and WUEi under the elevated atmospheric CO2 concentration increased, while the stomatal conductance (Gs) and intercellular CO2 concentration (Ci) decreased. With the increase of light flux intensity, the Pn and WUEi under the elevated atmospheric CO2 concentration were higher those under ambient atmospheric CO2 concentration, Gs was in adverse, while Ci and Tr had less change. At high fertilization rate of N, the Gs was linearly positively correlated with Pn, Tr, and WUEi, and the Gs and Ci had no correlation with each other under the elevated atmospheric CO2 concentration but negatively correlated under ambient atmospheric CO2 concentration. At low fertilization rate of N, the Gs had no correlations with Pn and WUEi but linearly positively correlated with Ci and Tr. It was suggested that under the elevated atmospheric CO2 concentration, the wheat leaf Pn at low N fertilization rate was limited by non-stomatal factor.

[Effect of investment for titanium crown and bridge on reactive layer of castings].

OBJECTIVE: To investigate the effect of self-developing investment (FUS-invest) on the reactive layer of titanium castings. METHODS: Three 10 mm x 10 mm x 1 mm pure titanium castings were founded using FUS-invest. Metallographical structure of reactive layer was observed. X-ray diffraction (XRD) and scanning electron microscope with energy-dispersive spectrum (EDS) were used to analyze the status of composition of the casting surface. Micro-Vickers hardness was measured. RESULTS: The metallograph indicated that the reactive layer was composed of coarse flake-shaped alpha phase of grains. The value of micro-Vickers hardness with the range 243 to 314 MPa had not significantly difference under the depth of 105 microm beneath the surface. The XRD pattern clearly showed the peaks of ZrO2, SiO2, Mg2TiO4 and TiO2. EDS analysis demonstrated that the main elements were Al, Si, Zr and Cl. CONCLUSION: FUS-invest is suited for pure titanium casting because of the thin reactive layer and less change to metallographical structure.