The effects of 2-hydroxyethyl methacrylate on the proliferation and migration of human dental pulp cells / 实用口腔医学杂志

Objective:To assess the effects of HEMA on the proliferation and migration of human dental pulp cells(hDPCs).Meth-ods:hDPCs were obtained using tissue explant culture technique in vitro,and then cells of the 3rd -5th passages were treated by differ-ent concentrations of HEMA for 24,48 and 72 h respectively.Cell proliferation was examined by MTT assay.Cell migration was ob-served by Transwell method.Results:The proliferation ability of hDPCs decreased when exposed to HEMA in both time and concentra-tion dependent manner(vs control,P <0.05).Cell proliferation at 24 h expossure was statistically higher than that at 48 h and 72 h(P<0.05).The migration of hDPCs was significantly reduced in HEMA groups at different concentrations(vs control,P <0.05).Con-clusion:HEMA inhibits the proliferation and migration of human dental pulp cells in vitro.

Research progress on nano-silver base inorganic antibacterial agents used in denture resin base / 实用口腔医学杂志

In recent years,nano-silver base inorganic antibacterial agents have been widely used in medicinal and biological fields.The recent research progress on nano-silver base inorganic antibacterial agents used in denture resin base,antibacterial effects,biocompatibility and the influence of the agents on the mechanical properties and color of the resin are introduced.

Three methods with functions of modification on aluminum borate whisker and with influence on flexural properties of dental composite resins / 生物医学工程学杂志

The present paper is aimed to discuss the influence of three different ways on modification of aluminum borate whiskers (AlBw) and on flexural properties of dental composite resins. In Group A, AlBw and silicon dioxide (SiO2) nanoparticles were thermally fused directly under certain processes. In Group B, Si-O network was formed on the surface of AlBw via the sol-gel process of tetraethoxysilane, then thermally fused with SiO2 nanoparticles to form AlBw-SiO2 compound as inorganic fillers. In Group C, SiO2 nanoparticles were repaired by sol-gel method of tetraethoxysilane under certain processes, and were deposited in the surface of AlBw. The mixtures were fused with high temperature sintering method. The effects of the surface morphology of AlBw with different ways were characterized by TEM and SEM. Then the mixtures were polymerized with resin matrix after surface siliconization and their flexural strength and Young's modulus were determined. SEM was used to examine specimen fracture surfaces. The results showed that the flexural properties of dental composite resins were significantly improved after whiskers were modified. Different methods produce different effects. Flexural strength of the Group A is (95.28 +/- 4.53) MPa. The results of TEM and SEM revealed that the aggregation was obvious between AlBw and SiO2 nanoparticles. Flexural strength of the Group B was (123.14 +/- 17.37) MPa. The results of TEM and SEM revealed that the dispersity was improved but SiO2 nanoparticles also reunited. AlBw were modified with nanometer-size SiO2 particles which were prepared by sol-gel method based on tetraethyl orthosioate (TEOS), the flexural properties of a new type of dental composite resins was (130.29 +/- 8.38) MPa. The results of TEM and SEM revealed that better dispersion between AlBw and SiO2 nanoparticles occurred. The SiO2 nanoparticles were fused and attached onto the surface of AlBw uniformly.

Research on adhesive strength of different composites resin core and fiber posts / 实用口腔医学杂志

Objective:To study the adhesive strength between fiber posts and four different composite resin core materials.Methods:Four resin core materials (Multicore Heavy Body、LuxaCore、 LIGHT-CORE and Z100) were placed around the fiber posts. The adhesive strengths of the samples were tested by the universal electrical testing machine. The interface between fiber post and resin core was observed by SEM. Results:Different resin core materials exhibited significant different influences on adhesive strengths(P<0.05). The LuxaCore reached the maximum of (314.31±15.36) N and the Z100 was the minimum of (267.39±10.54) N.Conclusion:Resin core material exhibits a significant influence on adhesive strength. The dual-curing composite core material with low viscosity has the highest bond strength in all groups.