Dental amalgam controversy of mercury released from amalgam restorations, especially during placement and removal, has not been shown to cause any other adverse health effects." The paper goes on to say that there have been "no controlled studies published that show adverse systemic effects" from amalgam restorations and there is no evidence that removing amalgam restorations relieves any general symptoms. More recently, FDI has published a resolution confirming that their position on the safety and effectiveness of amalgam has not changed despite the phasing-down in some countries In the United States, numerous respected professional and non-profit organizations consider amalgam use to be safe
Chemical element or an electrophile; similarly "Nu" denotes a nucleophile. "L" is used to represent a general ligand in inorganic and organometallic chemistry. "M" is also often used in place of a general metal. At least two additional, two-letter generic chemical symbols are also in informal usage, "Ln" for any lanthanide element and "An" for any actinide element. "Rg" was formerly used for any rare gas element, but the group of rare gases has now been renamed noble gases and the symbol "Rg" has now been assigned to the element roentgenium. Isotopes are distinguished by the atomic mass number (total protons and