Effects of body-shade resin layer thickness on the color of polyetheretherketone-Crea.lign restorations / 华西口腔医学杂志

OBJECTIVE@#This study aims to assess the effects of the different thicknesses of body-shade resin layers on the color of polyetheretherketone (PEEK)-Crea.lign restorations.@*METHODS@#Five PEEK specimens with the thickness of 0.6 mm were prepared. The color values of PEEK specimens were measured. Afterward, opaque-shade resin layers (0.1 mm) and body-shade resin layers (1.5 mm) were stacked with mold. The five specimens were evenly ground to a thickness of 1.4, 1.2, 1.0, 0.8, 0.6, 0.4, 0.2, and 0.0 mm in sequence. After grinding and ultrasonic cleaning, the color value was measured.@*RESULTS@#With the constant thickness of PEEK and 0.1 mm thickness of opaque-shade resin layer, the L*, a*, and b* values all showed downward trend with the increased thickness of the body-shade resin layer (1.0-1.4 mm). With the constant thickness of PEEK and 0.1 mm thickness of opaque-shade resin layer, the color difference between the adjacent groups was less than 1.5 NBS. This difference between nonadjacent groups was more than 1.5 NBS when the thickness of the body-shade resin layer reached 0.6 mm. Color difference between PEEK-Crea.lign restoration and PEEK was more than 1.5 NBS.@*CONCLUSIONS@#The thickness change in the body-shade resin layers influence the color of the PEEK-Crea.lign restorations. Using A2 shade Crea.lign, opaque-shade resin layer thickness is 0.1 and 0.6 mm thickness of body-shade resin layer can produce color which clinically acceptable.

MiRNA-365 and miRNA-520c-3p respond to risperidone treatment in first-episode schizophrenia after a 1 year remission / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>MicroRNAs (miRNAs) control gene expression by destabilizing target transcripts and inhibiting their translation. Aberrant expression of miRNAs has been described in many human diseases, including schizophrenia. However, the effects on miRNA expression in response to antipsychotic treatment in peripheral circulation have not been thoroughly examined.</p><p><b>METHODS</b>Using quantitative real-time PCR (qRT-PCR), We quantified the expression of seven candidate miRNAs in plasma samples of 40 first-episode schizophrenics before and after antipsychotic treatment. The patients were all treated with risperidone and achieved remission in 1 year.</p><p><b>RESULTS</b>Compared with the baseline, the expression levels of miR-365 and miR-520c-3p were significantly down-regulated after 1 year of risperidone treatment (P < 0.001). There were no significant correlations between the clinical symptoms and the expression levels of these two miRNAs (P > 0.05).</p><p><b>CONCLUSIONS</b>This study analyzed possible circulating miRNAs in response to antipsychotic monotherapy for schizophrenia, the further mechanism need to be confirmed.</p>

Influence of nano-silica content on flexural properties of the aluminum borate whisker and silica filler composite resins / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To discuss the influence of nano-silica content which was hydrolyzed by tetraethyl orthosioate (TEOS) on the aluminum borate whisker (AlBw) and silica filler composite resins on flexural properties.</p><p><b>METHODS</b>The nanometer-size silicon dioxide (SiO2) particles were prepared by sol-gel method based on tetraethyl orthosioate. Different proportion of AlBw and SiO2 were fused and attached onto the surface of AlBw through high temperature, then polymerized with resin matrix after surface siliconization and their flexural strength and flexural modulus were determined. The effects of heat treatment to the surface morphology of AlBw and the shapes of the mixture at various proportions were characterized by TEM.</p><p><b>RESULTS</b>The flexural properties of dental composite resins with AlBw-SiO2 compound as inorganic fillers were significantly improved. The flexural property of a new type of dental composite resins was(130.29 +/- 8.38) MPa, when the mass ratio of AlBw and nano-SiO2 particle was 3:1.</p><p><b>CONCLUSION</b>Nano-silica content which was hydrolyzed by tetraethyl orthosioate improved flexural properties of the aluminum borate whisker and silica filler composite resins.</p>