[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.

[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.

[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 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.

[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).

[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).

[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.

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.

[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.

[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.

[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.

New nano-sized Al2O3-BN coating 3Y-TZP ceramic composites for CAD/CAM-produced all-ceramic dental restorations. Part I. Fabrication of powders.

Partially sintered 3 mol % yttria-stabilized tetragonal zirconium dioxide (ZrO(2), zirconia) polycrystal (3Y-TZP) ceramics are used in dental posterior restorations with computer-aided design-computer-aided manufacturing (CAD/CAM) techniques. High strength is acquired after sintering, but shape distortion of preshaped compacts during their sintering is inevitable. The aim of this study is to fabricate new machinable ceramic composites with strong mechanical properties that are fit for all-ceramic dental restorations.

[Study of the bonding strength of pure titanium and light-cured hard crown and bridge composite after filming by TiSiN].

Objective: To evaluated the bonding strength between pure titanium and Solidex after deposition by magnetron sputtering TiSiN with different content of Si (9%, 19%) and analyzed the surface component by electron probe micro-analysis (EPMA).

Methods: All pure titanium samples divided into 3 groups according to different surface treatment, then bonded with Solidex light-cured composite. Material test machine was used to measure bonding strength and the surface was analyzed by EPMA.

[Effects of the improved FUS-invest investment for zirconium-oxide titanium crown and bridge on the reaction layer].

Objective: To investigate the effects of the improved FUS-invest investment for zirconium-oxide titanium crown and bridge on the reaction layer.

Methods: 10 mm x 10 mm x 1 mm titanium castings were invested. Spectrum analysis was done to its reaction layer, the metallographic examination was observed and Vickers hardness was measured.

[Exploration and classification in the amount of die stone of working cast model of denture restoration].

Purpose: The objective of this study was to survey the amount of working cast model of denture restoration, and to calculate the amount of die stone powder of each working cast model, then to classify the working cast model, with the expectation to perfuse the working cast model in clinic according to this classification, and to achieve the goal of increasing quality of working cast model and saving materials.

Methods: 311 working cast models were selected to perfuse with three kinds of tray including small size, middle size and large size randomly in clinic. The amount of die stone powder of working cast model was calculated, and the data were analyzed using SPSS 13.

[Study of TiN plating coat on increasing shear bond strength].

Purpose: To investigate the feasibility of increasing bond strength of polymer ceramic to titanium using TiN coating.

Methods: Twelve pure titanium specimens were casted and divided into two groups randomly. In one group,the surface was processed with conventional handling,in the other group,the surface was coated with TiN.

[Clinical evaluation of bovine colostrum containing oral hyaloplasmic gel on satisfaction of complete denture in xerostomia patients].

Purpose: The purpose of this study is to investigate the effect of bovine colostrum-containing gel on the satisfaction of wearing complete denture in xerostomia patients.

Methods: 23 edentulous patients with xerostomia and complete denture were employed to assess the differences of satisfaction after the gel was used in their dry oral cavity one week,one month and three months by using satisfaction questionnaire. The statistical analysis was carried out with SPSS11.

[Cr-Ti-Al-N complex coating on titanium to strengthen Ti/porcelain bonding].

Objective: To study the feasibility of magnetron sputtering Cr-Ti-Al-N complex coating as an interlayer on titanium to enhance the titanium-ceramic binding strength.

Methods: With a three-point bending test according to ISO 9693, the binding strength of Duceratin (Degussa) to titanium substrate prepared with 4 different surface treatments (polishing, polishing and megnetron sputtering Cr, Ti, Al, and N complex coating, sandblasting, sandblasting and coating) was evaluated. Ti/porcelain interface and fractured Ti surface were examined using scanning electron microscopy with energy-dispersive spectrometry (EDS).

[A study of mandible chewing movement in patients with developmental lateral jaw deformity].

Objective: The purpose of the present study was to investigate effects of developmental lateral jaw deformity (DLJD) on masticatory movement.

Methods: Three coordinates of mandibular movement signals were recorded in 35 young healthy adults with normal occlusion and 28 patients with DLJD by means of a Sirognathography System during gum chewing movement. Paired and unpaired t-tests were used to compare significant difference of intra-group and inter-groups in displacement and speed.

[Effect of mold temperature on mechanical properties of Ti-Zr alloy castings].

Objective: To investigate the influence of mold temperature on the mechanical properties of Ti-Zr alloy castings.

Methods: Ti-Zr alloy was cast into a mold which was made of a zircon (ZrO2.SiO2) investment with a casting machine (China) designed as vacuum, pressure and centrifuge.

[The effect of casting techniques on the accuracy of titanium crown and bridge].

Objective: To investigate the method of enhancing the accuracy of titanium crowns by improving the casting method.

Methods: A self-assembled die was used to fabricate 48 standardized wax crowns. The dies were averagely divided into two groups.

[The bonding characteristic of titanium and RG experiment porcelain].

Objective: To study the bonding characteristic of Titanium and RG experiment porcelain.

Methods: 5 specimens with a size of 10 mm x 5 mm x 1.4 mm were cast from pure titanium.