[Osteogenesis of human adipose-derived mesenchymal stem cells-biomaterial mixture in vivo after 3D bio-printing].

Objective: To construct human adipose-derived mesenchymal stem cells (hASCs)-biomaterial mixture 3D bio-printing body and detect its osteogenesis in vivo, and to establish a guideline of osteogenesis in vivo by use of 3D bio-printing technology preliminarily.

Methods: P4 hASCs were used as seed cells, whose osteogenic potential in vitro was tested by alkaline phosphatase (ALP) staining and alizarin red staining after 14 d of osteogenic induction. The cells were added into 20 g/L sodium alginate and 80 g/L gelatin mixture (cell density was 1 × 10(6)/mL), and the cell-sodium alginate-gelatin mixture was printed by Bioplotter 3D bio-printer (Envision company, Germany), in which the cells'survival rate was detected by live- dead cell double fluorescence staining.

[Short-term effect of CaCl₂on human adipose-derived mesenchymal stem cells proliferation and osteogenic differentiation].

Objective: To examine the effect of CaCl₂, a sodium alginate crosslinker, to stimulate cells for a short time period on human adipose-derived mesenchymal stem cells (hASCs) proliferation and osteogenic differentiation ability, and to determine the appropriate concentration of CaCl₂for post three-dimensional biological experiments.

Methods: hASCs stimulated with or without CaCl₂at various concentrations were seeded and cultured in control medium and osteogenic medium, respectively. The cell counting kit-8 (CCK8) was used to estimate the cell proliferation level of each group.

[Chemical constituents of Sapium sebiferum leaves].

Chemical constituents of ethyl acetate extract of Sapium sebiferum leaves were isolated and purified by various chromatographic methods, including column chromatographies over silica gel, macroporous adsorption resin, and Sephadex LH-20, as well as preparative TLC and semi preparative HPLC. As a results, 15 compounds were separated from Sapium sebiferum leaves and their structures were examined by spectral analysis including NMR and MS data and identified as( + )-(7R,7'R,7"S,7'"S,8S,8'S,8"S,8'"S)-4", 4"'-dihydroxy-3,3',3",3',5,5'-hexamethoxy-7,9';7',9-diepoxy-4,8";4',8'"-bisoxy-8,8'-dineo-lignan-7",7"',9",9"'-tetraol(1) ,1-(4'- hydroxy-3'-methoxyphenyl)-2-[4"-(3-hydroxypropyl) -2", 6"-dimethoxyphenoxy] propane-1, 3-diol (2), Thero-2, 3-bis-(4-hydroxy-3- methoxypheyl)-3-methoxy-propanol(3) , threo-5-hydroxy-3,7-dimethoxyphenyl propane-8,9-diol (4), boropinol B (5), threo-8S-7-methoxysyringylglycerol(6), 5-hydroxymethylfurfural(7), 5-( methoxy-methyl)-1H-pyrrole-2-carbaldehyde (8), quercetin (9) , kaempferol (10), ethyl gallate(11), coniferaldehyde(12), vanillin(13), 7-hydroxy-6-methoxy-2H-1-henzopyran-2-one(14),and 1-heptacosanol (15). All compounds except for compounds 9-11,14 were separated from this plant for the first time.

[Quantitative assessment on artifacts of dental restorative materials in cone beam computed tomography].

Objective: To quantitatively evaluate the artifacts appearance of eight kinds of common dental restorative materials, such as zirconia.

Methods: For the full-crown tooth preparation of mandibular first molar, eight kinds of full-crowns, such as zirconia all-ceramic crown, glass ceramic crown, ceramage crown, Au-Pt based porcelain-fused-metal (PFM) crown, Pure Titanium PFM crown, Co-Cr PFM crown, Ni-Cr PFM crown, and Au-Pd metal crown were fabricated. And natural teeth in vitro were used as controls.

[Quantitative evaluation for the accuracy of dental model three-dimensional scanner].

Objective: To establish a method to evaluate dental model three-dimensional scanner quantitatively, and to evaluate the accuracy which is a core indicator of 3Shape D700 scanner.

Methods: A standard geometric model similar to the dental arch was designed by three-dimensional reverse software and processed by high precision CNC (computer numerical control) processing technology. Core indicators of dental model three-dimensional scanner including single scanning accuracy, space consistency and rescan accuracy were evaluated.

[Three dimensional bioprinting technology of human dental pulp cells mixtures].

Objective: To explore the three dimensional(3D)bioprinting technology, using human dental pulp cells (hDPCs) mixture as bioink and to lay initial foundations for the application of the 3D bioprinting technology in tooth regeneration.

Methods: Imageware 11.0 computer software was used to aid the design of the 3D biological printing blueprint.

[Digital inlaid design based on anatomical characteristics and preliminary implementation of its program].

Objective: To explore the technical guideline of inlays computer aided design (CAD) for further development, to test the feasibility of processing for the design results of the technical guideline, and to assist co-operation with automatic inlay CAD software development.

Methods: On the basis of point cloud data of right mandibular first molar of standard crown, we established the coordinate system,the landmarks and lines and the characteristic curves. A dental cast of right mandibular first molar MOD-inlay of an individual normal occlusion was scanned.

[Study on low temperature degradation of dental zirconia ceramic].

Objective: To evaluate the properties of low temperature degradation (LTD) of dental Y-TZP by experiments.

Methods: According to ISO 13356-2008 standards, 72 blanks of Y-TZP were sintered at different temperature (1 400 °C,1 450 °Cor 1 530 °C) and in different heat preserving time(2 h or 5 h), and then the specimens were grounded and polished. The blanks were divided into 12 groups according to the different sintering temperature, heat preserving time and aging time.

[Three-dimensional model analysis of the gingival sulcus width from different retraction time].

Objective: To explore the effect of gingival retraction time on the gingival sulcus width in different gingival areas, using three-dimensional (3D) model analysis.

Methods: Forty-six premolars from 10 volunteers were included, gingival retraction cords were applied on the buccal sulcus for three times, and the retraction time was 5, 10 and 15 minutes respectively. The least interval between two retraction procedures was 2 weeks.

Coordinated control and experimentation of the dental arch generator of the tooth-arrangement robot.

Background: The traditional way of acquiring the dental arch curve form is based on manual operation, which will randomly bring numerous errors caused by human factors. The purpose of this paper is to automatically acquire the dental arch curve and implement the coordinated control of the dental arch generator of the multi-manipulator tooth-arrangement robot, which can be used in full denture manufacturing.

Methods: Based on the arc length constant theory, kinematics on dental arch generator is analyzed.

[Computer-aided design for occlusal rest of the removable partial denture].

Objective: To explore the route of automatic computer-aided design for occlusal rest of the removable partial denture.

Methods: A new module for the design of occlusal rest was developed. The three-dimensional data of a partially dentate dental cast was obtained and imported into the new module.

[Methodology of computer-aided design of automatic artificial tooth selection for complete denture].

Objective: To study the method of automatic tooth selection for computer-aided design in complete denture, evaluate the results by comparison with traditional denture tooth selection.

Methods: 3D data of occlusal rim made by the dentist were obtained with a 3D laser scanner and specific points on the occlusal rim were measured on Imageware11 platform. Based on Matlab 7.

[Measurement and estimation of the root surface of single-root teeth].

Objective: To evaluate the availability of the estimation method of the single-root surface area on periapical radiographs, and to compare with the measured method by 3-dimension laser scanning and reconstructed images.

Methods: Ninety single-root teeth with severe periodontitis were selected, periapcal radiographs were taken before teeth extracted. Root lengths and crown lengths were measured on periapical radiographs.

[A method for three-dimensional analysis of occlusal contacts from digital dental casts].

Objective: The study was to investigate the occlusal contacts with a set of dental casts based on their three-dimensional models in the intercuspal position.

Methods: 3D point-clouds of the dental casts in the intercuspal position were acquired by D.02-L-3D scanner with a special casts-locating device, and reconstructed .

[Construction of inlay axial surface using B-Spline curve network].

Objective: To realize the requirement of adjacent area accuracy, axial surface physical contour and smoothness in the process of inlay computer-aided design (CAD).

Methods: A compromised method was brought forward that some assistant 3-D constraint lines from occlusion to gingiva were used to lead the inlay contour on axial corner and other characterized areas, and two perpendicular 3-D constructing lines at adjacent area were used to construct accurate 3-D configuration of this area. The axial surface was completely defined by the network of specified curves which were two constructing lines and four borders.

[3D-data acquisition of partially edentulous cast using grating projection method].

Objective: A method for 3D-data acquisition of partially edentulous cast was introduced to lay the foundation for reconstructing 3D digital model of a partially edentulous cast and studying computer aided design (CAD) to a removable partial denture framework.

Methods: Using projection system controlled by a computer, four frames of sinusoidal fringe pattern at pi/2 intervals were projected onto the surface of partially edentulous cast consecutively within 0.4 second.

[A scanning method for the dental casts of intercuspal position].

Objective: To acquire the 3D point-cloud of the dental casts of intercuspal position and rebuild it in computer.

Methods: A special scanning method was used to acquire the point-cloud of dental cast by using the D.02-L-3D SCANNER and rebuild the model by computer.

[Design of geometric models of the removable partial denture framework].

Purpose: The aim of this study was to introduce a method on computer aided design (CAD) of removable partial denture(RPD) framework based on domestic CAD/CAM software system, which contributes to the further research to develop the domestic software system applied in restorative dentistry.

Methods: Point cloud data of a partially edentulous cast, a mandibular Kennedy Class II modification 2 arch, was captured by an optical scanning system with projective grating and high-resolution digital camera. Using domestic CAD/CAM software system, the above point cloud data was reduced, digital surveying line and inserting path were determined.