Dental amalgam controversy demonstrated that mercury released from amalgam restorations does not give rise to toxic effects on the nervous system of children. More recently, a Cochrane Systematic review in 2014 found, "insufficient evidence to support or refute any adverse effects associated with amalgam or composite restorations." Those opposed to dental amalgam suggest that mercury from dental amalgam may lead to nephrotoxicity, neurobehavioural changes, autoimmunity, oxidative stress, autism, skin and mucosa alterations, non-specific symptoms and complaints, Alzheimer's disease, and multiple sclerosis. Both those opposed and those not opposed to dental amalgam recognize that amalgam has been found to be a rare contributor to
Amalgam (dentistry) as pins, slots, holes and grooves can be used for the retention of large amalgam restorations, but they do not reinforce the amalgam or increase its strength. There is no current scientific evidence to justify the extra cost and effort associated with the use of adhesively bonded amalgam restorations in comparison with nonbonded amalgam restorations. In view of the lack of evidence on the additional benefit of adhesively bonding amalgam compared with nonbonded amalgam, it is important that clinicians are mindful of the additional costs that may be incurred. The placement of amalgam restorations can potentially cause sensitivity post-operatively. According