White Fillings Versus Dental Amalgam Fillings

Andrea Clarke has been peering into people’s mouths for nearly 30 years, wondering why teeth with old dental amalgams fracture or break up and why there is almost always dental decay beneath them when she goes to fix them. At Milford Dentists, North Shore, Andrea and her team haven’t placed a dental amalgam filling since 1999. They have placed white fillings aka composite resin fillings successfully instead – this is because white filling bio-mimics tooth structure i.e. it behaves very similarly to the tooth that has decayed or snapped off that it is replacing

As Andrea explains, “Over the last couple of years clever researchers, some of whom are dentists have worked out why dental amalgam fillings end up making teeth snap, fracture and decay; eventually making the tooth fail. This has reinforced my own theories that Mercury Dental amalgam fillings are a disaster for teeth and conversely white composite resin fillings are a much better more biomimetic (life like) alternative.”
Andrea goes on to say, “Around 50% of dental amalgam is made up of mercury. Mercury has been used in thermometers for years because it expands and contracts a great deal with temperature change. So when you, say, have a hot drink, the mercury in your dental filling heats up and expands making the filling bigger. This puts a whole lot of pressure on your tooth and eventually your tooth can’t take the strain and cracks/fractures/snaps. Conversely when you have something cold to eat or drink – say ice cream, your filling contracts leaving a gap around it. Conversely white bonded composite resin fillings have a similar co-efficiency of expansion as tooth with temperature change i.e. composite resin expands and contracts just like your tooth with temperature variations. White fillings are also bonded or “glued” into the tooth cavity which means there are no gaps around the edges.

“Because mercury dental amalgam is a hole filler it needs to be “keyed” or locked into the tooth by undercuts so that it doesn’t fall out.  As already mentioned a bonded composite resin filling glues the tooth back together and because white fillings are bonded they do not need to be “keyed” into the tooth. This means cavities for white fillings are smaller than corresponding cavity shapes for an amalgam filling.”

Milford Dentists is proud to help the good people of the North Shore with all their dental requirements - From Devonport and Belmont up through Takapuna, Castor Bay,Mairangi Bay and Browns Bay as well as Albany, Northcote, Hillcrest & the Whangaporoa Peninsula. For more information please go to http://www.milforddentists.co.nz