The apoptotic and autophagic effects of cast Au-Pt, and differently manufactured Co-Cr and cp-Ti on three-dimensional oral mucosal model

Influence of fabrication method on the biological properties of modified PEEK

To investigate the influence of fabrication method on the biological properties of modified PEEK. Two materials were tested in this study: press and CAD/CAM milled ceramic-reinforced PEEK (BioHPP, Bredent, Germany). The residual diphenyl sulfone in these two materials was detected and their biological effects on human gingival fibroblasts (HGFs) were evaluated by assaying cell viability, apoptosis, and inflammation. Diphenyl sulfone was not detected in press and milled BioHPP. The cell viability of them complied with ISO standards. The mRNA expression levels of Bax and Caspase-3 were up-regulated and that of Bcl-2 was downregulated when HGFs were cultured with the eluates of these two materials. There was no difference in cell viability, apoptosis, and inflammation between them. Hence, the fabrication method did not affect the biological properties of modified PEEK, the press and CAD/CAM milled modified PEEK all presented favorable cytocompatibility despite the expression of apoptosis-associated genes at the mRNA level.

lncKRT16P6 promotes tongue squamous cell carcinoma progression by sponging miR‑3180 and regulating GATAD2A expression

Tongue squamous cell carcinoma (TSCC) is characterized by a poor prognosis and its 5‑year overall survival rate has not improved significantly. However, the precise molecular mechanisms underlying TSCC remain largely unknown. Through RNA screening, the present study identified a novel long noncoding RNA (lncRNA), keratin 16 pseudogene 6 (lncKRT16P6), which was upregulated in TSCC tissues and cell lines and associated with TSCC tumor stage and differentiation grade. Inhibition of lncKRT16P6 expression reduced TSCC cell migration, invasion and proliferation. lncKRT16P6 sponged microRNA (miR)‑3180 and upregulated GATA zinc finger domain containing 2A (GATAD2A) expression. miR‑3180 inhibition reversed the lncKRT16P6 depletion‑induced attenuation of TSCC malignancy and GATAD2A depletion reversed the miR‑3180 silencing‑induced enhancement of TSCC malignancy. In summary, the present study revealed a potential competitive endogenous RNA (ceRNA) regulatory pathway in which lncKRT16P6 modulates GATAD2A expression by binding miR‑3180, ultimately promoting tumorigenesis and metastasis in TSCC. Therefore, lncKRT16P6 may be used as a prognostic biomarker and therapeutic target for clinical intervention in TSCC.

Comparative analysis of leaching residual monomer and biological effects of four types of conventional and CAD/CAM dental polymers: an in vitro study

OBJECTIVES

The objective of this study is to investigate leaching residual monomer and biological effects of four types of conventional and computer-aided design/computer-aided manufacturing (CAD/CAM) dental polymers on human gingival fibroblasts (HGFs).

MATERIALS AND METHODS

A total of 540 disk-shaped specimens were fabricated from four different materials (n=135 per group): compression-molding polymethylmethacrylate (PMMA) (conventional denture polymer), CAD/CAM PMMA (CAD/CAM denture polymer), bis-acrylic composite resin (conventional temporary polymer), and CAD/CAM PMMA (CAD/CAM temporary polymer). Specimens were eluted in cell culture medium for 72 h at 37°C, and the residual monomer in eluates subsequently was measured by high-performance liquid chromatography (HPLC). The biological effects of material eluates on HGFs were analyzed by CCK-8 assay, flow cytometry, real-time quantitative PCR, Western blotting, and enzyme-linked immunosorbent assay (ELISA) to identify cell death patterns and its biological mechanism.

RESULTS

Methyl methacrylate (MMA) was detected only in compression-molding PMMA, and by-products were detected in bis-acrylic composite resin. The cell proliferation of CAD/CAM denture polymer or CAD/CAM temporary polymer was greater than that of compression-molding PMMA or bis-acrylic composite resin at 72 h in culture. No apoptosis and necrosis were detected in CAD/CAM dental polymers. Apoptosis was detected only in bis-acrylic composite resin and further confirmed by the upregulation of Bax and cleaved Caspase-3, as well as the downregulation of Bcl-2 gene. And no significant variation in inflammatory cytokines secretion was observed in all materials.

CONCLUSIONS

CAD/CAM dental polymers (including temporary and denture polymers) have favorable biocompatibility due to lower residual monomer, which provides scientific evidence to the controversy of biocompatibility of conventional and CAD/CAM dental polymers.

CLINICAL RELEVANCE

The use of CAD/CAM dental polymers is recommended in the fabrication of temporary restorations and dentures due to their favorable biocompatibility.