Ok this is what my sister said. (and bear with me. She talks a lot. lol.) And sorry I forgot to specifically ask about gold. I asked her now. Anyways. Here's what she said:
um it totally depends on which way you look at it.
what is a safe filling? um none :P because drilling in a tooth always risks trauma and upsetting the tooth.
but! it isnt safe to leave a cavity either so the safer option is to fix it.
so a white filling doesnt have any metal in it like the mecury that ppl are so afraid of. the thing about the silver fillings (amalgam) is that dentists like to use it because it doesnt matter if they get saliva on it or the tooth while you fix the tooth so it goes faster and you dont have to worry about it not bonding and needing to do it all over again. amalgam fillings are stronger tho so dentists also like them for that. what amalgam fillings have a tendancy tho to expand. the material overtime expands and goes back to normal, then expands and goes back to normal and so we see a lot of big amalgam fillings come back with cracks in the tooth, and if the crack is big enough it needs an onlay, crown, or extraction (if it is cracked down to the root part where we cant really save it anymore) thats why i dont like amalgam fillings because i think it doesnt matter if it is a good material because the point of a filling is to prevent more damage and if the silver filling can actually cause more damage in the long run it isnt something i would choose.
most ppl are worried about the mecury tho. you are only really exposed to any mecury when the filling is put in and when it is taken out because it is the vapours that get you the most. so i was told i school the only people really at risk is people filling their whole mouths with mecury, the assistants who have to handle the material and the dentists who put it in and carve it etc.
we find we remove them most because patients are unhappy with the look of them.
whereas with white fillings (composite fillings) do not expand at all. they do the opposite. white fillings shrink. so say you get a white filling and in like 10-15 years it shrinks to the point you get more decay because it does what we call "microleakage" ,basically it separates from the tooth. Now this is waaaay easier to fix than a tooth that as cracked from the expansion of a silver filling. because all you need to do to old white fillings then is just clean out the old filling and replace it.
white fillings look better because they are tooth coloured and we can match the shade to the teeth.
the main problem with white fillings is that it has a hard time bonding to the tooth. we have to use a etch, primer and bond to make it stay in the tooth. but if saliva say touches the tooth after we etched it but not bonded it then we need to start over, if saliva touches our uncured filling material we need t start over. so it can take waaay longer because we need to make sure everything is dry so that the filling is bonded properly.
the consequence of a filling not bonded properly is shorter life expectancy. and if it is a front tooth and you like fixed a chip and the bonding failed.... well the material just falls out because thats what holds it together.
it is really cool actually. well to me it is. the etch and primer opens up the tubules in the dentin and then the bond flows in there and when the material goes in it kind of mechanically holds the material in because it is held into the tubules of the dentin. so if that is contaminated with saliva it doesnt work properly.
on the whole most dentists i know just do white ones anyways unless someone asks specifically for amalgam or if insurance doesnt cover it or if a kid is really hard to work on....
next problem: insurance companies. White fillings cost more money..... A lot of insurance companies dont pay for white fillings on back teeth. often they will cover the portion of what an amalgam filling costs on the back teeth and make you pay the difference. just keep that in mind if you get a weird statement of how much to pay. it is a flaw that we dont like about insurance companies because it makes us look bad when we charge them more than they expected. they will pay for white fillings on teeth you can see tho.
so now you know my chapter on composites vs amalgam.
what i tell patients when they come in and ask what to get i usually say that for the most part we do white, most patients dont want to see the filling, and i let them know it takes a bit longer than the silver fillings but you get a better filling. and that often i think makes them feel better when they find out it also cost more. it costs more mostly because it takes more of our time and it has more expensive materials, plus we need like dental dams and stuff to keep it dry. or lots of cotton rolls etc. so ya..
oh white fillings are usually more sensitive after too. if you get sensitivity from fillings a deep white filling might be sensitive for 2-3 weeks after. but! if it is annoying you then you should always go in and get them to like check the bite of it and stuff because a lot of the time you are frozen and so the way you ite together has changed and since u are frozen u cant tell if it is back to normal and when the freezing comes out it will feel really odd and annoying like u got something stuck on your tooth. and if thats the case always always always go get it adjusted because it WONT ever go away on its own okay