Dental amalgam controversy Dental amalgam controversy This discussion of the dental amalgam controversy outlines the debate over whether dental amalgam (the mercury alloy in dental fillings) should be used. Supporters claim that it is safe, effective and long-lasting while critics argue that claims have been made since the 1840s that amalgam is unsafe because it may cause mercury poisoning and other toxicity. Supporters of amalgam fillings point out that it is safe, durable, relatively inexpensive, and easy to use. On average, amalgam lasts twice as long as resin composites, takes less time to place, is tolerant of saliva or blood contamination during placement
Real element formula_1, Every involution is strongly real. Furthermore, every element that is the product of two involutions is strongly real. Conversely, every strongly real element is the product of two involutions. If and formula_1 is real in formula_2 and formula_30 is odd, then formula_1 is strongly real in formula_2. The extended centralizer of an element formula_1 of a group formula_2 is defined as making the extended centralizer of an element formula_1 equal to the normalizer of the set The extended centralizer of an element of a group formula_2 is always a subgroup of formula_2. For involutions or non-real elements, centralizer and