In dentistry, amalgam is an alloy of mercury with various metals used for dental fillings. It commonly consists of mercury, silver, tin, copper, and other trace metals.In the 1800s, amalgam became the dental restorative material of choice due to its low cost, ease of application, strength, and durability.
Recently however, its popularity has diminished somewhat.Concern for aesthetics, environmental pollution, health, and the availability of improved, reliable, composite materials have all contributed. In particular, concerns about the toxicity of mercury have made its use increasingly controversial.
FEATURES
1) Strength:
The strength of amalgam is extremely important, since it must be able to withstand significant loads produced during mastication and any power shortage is likely to result in destruction of occlusion.
2) Corrosion:
The amalgam corrodes in the oral environment.The corrosion is often referred to as an advantage, since the corrosion products help create better contact between tooth and amalgam.
3) Dim:
The amalgam dazzles quite easily and loses its shine.
4) Poor aesthetics:
We can an only use amalgam for fillings in the back teeth because it has higher strength but it still creates an ugly result.
TOXICITY OF MERCURY
It can not be denied that mercury is a toxic substance and its use requires attention. The main sources of mercury exposure arise from:
- random leak
- bad mercury hygiene
- direct contact with mercury
- mixer for amalgam manufacture
- placement of new and removal of old fillings
The most serious risk is through mercury vapor, and the largest source of mercury vapor is leakage into surgery.
Mercury poisoning signs:
- leg cramps
- itching
- rashes
- sweating
- tachycardia
- fever
- personality change
- insomnia
- hypertension
- headaches
- fatique
- nerve dysfuntion
Patients are definitely less exposed to risk from inhalation of mercury from the dental staff. Surely there is some absorption of inhaled mercury vapor during placement of new amalgam fillings, but this percentages are very low.However, there have been many cases when patients have reacted very badly to the presence of amalgam in their mouths,this occurs due to the delayed hypersensitivity reaction to mercury.
In addition to inhalation of mercury vapor, wear and corrosion contribute to the overall body burden of mercury. On average, the uptake of mercury in the body of the amalgam fillings is very low (30 ug / day) according to the World Health Organization. However, it should be appreciated that this is only an average and could even be some patients with larger amount of mercury in their bodies because of excessive and intense chewing or teeth grinding.
Athina Tsiorva