Release of calcium ions from particulate monosodium titanates for dental mineralization applications.

Purpose: The calcium ion [Ca(II)] release from monosodium titanates (MST) complexed to calcium ions [Ca(II)], referred to as MST-Ca(II), was examined under varying incubation times, pH conditions, and ion equilibrium disruptions.

Methods: Sample supernatants were analyzed for Ca(II) using the QuantiChrom Calcium Assay Kit.

Results: No Ca(II) was detected in native MST (control) supernatants but was detected in MST-Ca(II) supernatants.

Biological effects of Ni(II) on monocytes and macrophages in normal and hyperglycemic environments.

Corrosion and release of nickel ions from biomedical alloys are well documented, but little is still known about the effects of released nickel ions on cellular function with recurrent inflammatory challenges. Evidence suggests Ni(II) ions amplify LPS-induced secretion of several pro-inflammatory cytokines from monocytes. Exacerbating the inflammatory response, hyperglycemic conditions also affect monocytic function.

Violet/blue light activates Nrf2 signaling and modulates the inflammatory response of THP-1 monocytes.

Several studies suggest that light in the UVA range (320-400 nm) activates signaling pathways that are anti-inflammatory and antioxidative. These effects have been attributed to Nrf2-mediated upregulation of "phase 2" genes such as heme oxygenase-1 (HO-1) that neutralize oxidative stress and metabolize electrophiles. Proteomics analysis previously had shown that small doses of blue light (400-500 nm) increased levels of peroxiredoxin phase 2 proteins in THP-1 monocytes, which led to our hypothesis that blue light activates Nrf2 signaling and thus may serve as an anti-inflammatory agent.

Cytotoxicity of Titanate-Calcium Complexes to MC3T3 Osteoblast-Like Cells.

Monosodium titanates (MST) are a relatively novel form of particulate titanium dioxide that have been proposed for biological use as metal sorbents or delivery agents, most recently calcium (II). In these roles, the toxicity of the titanate or its metal complex is crucial to its biological utility. The aim of this study was to determine the cytotoxicity of MST and MST-calcium complexes with MC3T3 osteoblast-like cells; MST-Ca(II) complexes could be useful to promote bone formation in various hard tissue applications.

Zirconia in biomedical applications.

The use of zirconia in medicine and dentistry has rapidly expanded over the past decade, driven by its advantageous physical, biological, esthetic, and corrosion properties. Zirconia orthopedic hip replacements have shown superior wear-resistance over other systems; however, risk of catastrophic fracture remains a concern. In dentistry, zirconia has been widely adopted for endosseous implants, implant abutments, and all-ceramic crowns.