"Heck of a Switch"
Q: Dr. Crapo: Several years ago I read a magazine article on the dangers of mercury fillings. It was quite convincing so I decided to have my mercury fillings out and white ones put in. The dentist said he would do one quarter of my mouth at a time. After the first appointment, there was some sensitivity but the dentist said it would disappear, so we went ahead and did the second quarter just above the first set of fillings. Several days later I wondered when things would settle, as anything hot or cold or hard felt like a knife going through my teeth on that side. I went back and the dentist sanded some of the fillings but then said some of the fillings were quite large and might need a root canal. Fast forward to today – I’ve had three root canals, five crowns and one tooth with a root canal and crown extracted since getting those fillings changed. In the past two years, I’ve had three teeth break off on the other side but I’m afraid to have anything done because of what happened. Why did it happen? Should I have left the old silver fillings in? What do I do with the broken teeth – I’m afraid of the white stuff. Have you seen this before? I had no warning; do you not warn people these things can happen before the fact? Please respond.
A: White fillings for posterior teeth (mainly molars) have been a mixed blessing since their inception. For decades, the “scare has been on” for silver/mercury fillings. After thirty plus years the pressure is still on the profession to come up with a reliable “inexpensive” filling material that will give the service of silver fillings.
When silver is “changed out”, it’s imperative that the new filling is in perfect harmony with the bite. Molar teeth don’t like change – if it changes the way they’re forced to work against their chewing partner(s).
When extreme sensitivity is experienced, three things are possible – the filling is out of balance with the opposing teeth, the process of sealing the filling was faulty, or the tooth was on the verge of problems (pre-abscess, severe crack etc.). Usually it’s the first two. If the teeth are hitting improperly, that must be remedied. Because balancing the filling is complex (teeth are connected to very dynamic joints, muscles and ligaments), more than one visit may be required. If balancing doesn’t completely solve the sensitivity problem, the filling must be carefully redone, unless other problems were noted at the filling appointment.
To lose a tooth because of a filling change (leading to root canaling, crowning, then extraction) is extreme. White fillings require much more attention to detail than silver fillings and there are far more details to account for. “Switching out” fillings must be done with care.