Do you use metal seals?

Composition: mixed from 2 components: 50% liquid mercury and 50% metal alloy powder (silver, copper, tin, zinc). The metal seal has been hotly debated throughout its long life. In fact, no other material in dentistry has been so controversial. We will try to give a brief overview of the opinions of the ‘proponents’ and ‘opponents’: the proponents argue that it is a very strong, long-lasting, inexpensive filling, able to withstand a high chewing load. Once the metal filling is mixed, the mercury becomes inactive and the amount of mercury released into the body is too low to cause any tangible effect, making it a safe substance.

Recently, amalgams have been improved by changing the ratio of the metal components (increased copper content) and the use of a chemical bonding agent to improve shelf life. There is no reliable scientific evidence that these fillings are harmful to the body. The long-term use and popularity of amalgams is a guarantee of the quality of these fillings. Opponents consider that mercury, which is the most toxic non-radioactive element in a metal filling, is also the most volatile of the volatile metals, tasteless and odourless. Wearing a metal filling releases a constant amount of mercury into the body (1-29 milligrams/day, 10 milligrams/day is considered safe). Even small amounts are dangerous as they release a highly toxic element into the body. The amount released depends on the number of amalgams, the composition and quality of the mixture, and the location of the filling, whether on the chewing or other surface. Higher levels of mercury are released through the consumption of hot food and drink, chewing and brushing. Mercury accumulates in various human organs (mainly in the brain, which is why its most adverse effects are neurotoxic). Various studies have linked the release of mercury into the body to a number of neurological diseases (Alzheimer’s, Parkinson’s, autism) and autoimmune diseases (lupus, multiple sclerosis, etc.). The causes and triggering mechanisms of all these diseases have not yet been precisely identified.

Today, it is impossible to measure mercury levels in a living person’s body; blood and urine tests, as well as hair tests, do not show the true levels (only after an acute poisoning will there be a more pronounced increase); and mercury accumulates in the body organs, is excreted very slowly, and all tests show only trends. Amalgam does not have the chemical adhesion to the tooth that other modern fillings have (attempts to use a chemical bond are unreliable), so when preparing the tooth, the cavity needs to be shaped for good mechanical retention, which weakens the tooth walls (often over-filling the area most susceptible to fracture).

We are not on one side or the other; it is the job of scientists to prove the safety or danger of amalgams. However, as cosmetic dentists, we do not use these fillings because of the poor aesthetics. The emergence of new materials in dentistry makes it possible to restore the tooth not only aesthetically, but also to guarantee the necessary strength.