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Dental amalgam. Anette & Jenny. a nd why it is banned in Norway. Scandinavia ban the use of amalgam. In 1998 proposed a law that would gradually discontinue the use of mercury No mercury in thermometers
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Dental amalgam Anette& Jenny and why it is banned in Norway
Scandinavia ban theuseof amalgam In 1998 proposed a law that would gradually discontinue the use of mercury No mercury in thermometers Discussion between patient and dentist, where dentist recommends plastic filling materials Amg. is only recommended in cases where patient cant take care of oral hygiene (old, downs syndrome etc..)
Total mercury ban In 2008, Norway,Sweden andDenmark implemented a total mercury ban, which also ment amalgam as a tooth filling material. The reason for that is that mercury is a poiseous material, and it accumulates in aninmalsand people.
Amalgam • Has been used for over 100 years • Composition: • 45-50 % mercury • 20-40 % silver • 9 – 16 % tin • 9 – 16 % cupper
Properties • Good • It is cheap, easy to work with, its strong, durable, abrasion resistant, doesn’t interact with biological fluids, antimicrobial etc. • Bad - hydroscopic expansion, creep, brittle, amalgam only has a mechanical retention to the tooth, meaning you have to remove a lot more of the tooth substance than you would have for e.g. composite. Also, from an aesthetic point, it looks grey and silvery and will also discolour the rest of the tooth
Banning of dental amalgam 1st ofJanuary 2008 Most countriesusing amalgam find more advantagesthandisadvantages and do not understand thereason for the total ban of amalgam Theycall it ”The Scandinaviandisaster” Lackofgood arguments to stopthe usage of amalgams
Amalgam vs. composite Wearcharacteristics as toothtissue Corrosion - margin seal Bacteriostatic Do not require dry field (saliva, blood) Can be used for subgingivalfillings Longer lasting (up to 30 years)
Toxicity Toxic for our body Releaseoffree ions whenreactingwithothermetals Mercury is being taken up by fish It can cross the placenta and be harmful to the fetus of pregnant women It can result in allergies. There has been talk of people experiencing symptoms of mercury poisioning
Cancause: Small doses – hard to measuretheexactamountaccumulated Accumulationmainly in the liver and kidney Frequent contributor to oral lichenoid lesions Autoimmune diseases
Mercury poisioning • Tremors • Emotional changes (e.g., moodswings, irritability, nervousness,excessive shyness) • Insomnia • Neuromuscular changes (such asweakness, muscle atrophy) • Headaches • Disturbances in sensations • Changes in nerve responses
Mercury poisioning Impairmentoftheperipheralvision Disturbances in sensations (”pins and needles” feelings, usually in the hands, feet and aroundthemouth) Lackofco-ordinatedmovements Impairmentofspeech, hearing Muscleweakness
Effects for thedentist: • Mild effectwhencompared to general population • Accordingsomeresearch, dentistslaggedbehind in some areas, as: • Memory • Co-ordination • Motorspeed • Concentration • Increasedurinarymercurylevel • Kidneydisorders compared to normal population • Unknownifthis is linked to amg
How it canaffectthedentist: Important to use a low speed handpiecewithcoolingwhenpolishing a new amalgam filling If temperature is above 60 °C, theproperitesof amalgam are destroyed and it releases mercury
Most important isitsharmfuleffectontheenvironment.It is a poisenousmaterial that isunwanted in the nature.It findsitsway back tonature via sewers fromdental offices, cremations,industry etc.
WHO conclusion – mercurytoxicity 2003 Dental amalgam - most common form of exposure to mercury in the general population Intestinal absorption varies greatly among the various forms of mercury (dental amalgam is the least absorbed type) Absorption varies according bruxism Less fillings due to improved hygiene No relationship was observed between the mercury release from amalgam fillings and the mercury concentration in basal brain Even at very low mercury levels, subtle changes in visual system function can be measured MS patients with amalgam fillings, red blood cells, haemoglobin, hematocrit, thyroxine (T4) and T-lymphocytes levels are significantly lower, while blood urea nitrogen and hair mercury levels are significantly higher
Ourconclusion Considering all theadvantagesusing amalgam and thelackofgoodreasonswhyweshould ban thisfilling material, wedon’t support thisdecision. SinceNorway is a smallcountry, theenvironmentalconsequensesofus not using amalgam will not make a bigdifference world wide
Sources http://www.medicinenet.com/mercury_poisoning/page2.htm http://www.denpro.no/amalgam-forgiftning.html Norwegiandentistry journals