In my 25 years of practicing dentistry, I have heard reports of various types regarding dental treatment. Someone heard something from someone, or read it somewhere and they take it as fact. There are misconceptions regarding filling materials, wisdom teeth, dentures, bad breath, etc. How does one know what to believe?
The oral cavity is a vital organ of the body, just like any other organ. Just like any other organ which may become diseased, certain treatments are essential, while other types vary from person to person. For example, should all wisdom teeth be pulled? Some dentists feel all wisdom teeth should be pulled, others feel when they are impacted, while still others feel only if they are a problem. The criteria for extracting wisdom teeth should be that only if they present a problem they should be extracted. That is, if they are pushing on the adjacent teeth, and causing other movement of the teeth, then that is a problem. If they are hard to reach and clean, and contributing to gum disease, that is a problem. If they are infected and abcessed, this is a problem. If they are not causing any problems they should be left alone. Usually by the age of 25 whether they are a problem or not will be evident. Over the age of 35, they should only be extracted if there is a recurring infection that can’t be resolved or if the orthodontist recommends having them pulled because braces are being placed.
Fluoride is another very controversial issue. Do we fluoride our water supplies or give fluoride tablets to infants? Safe amounts of fluoride in drinking water are no more than 2ppm. Too much fluoride causes a condition called fluorosis, which affects developing teeth in children. The teeth appear chalky white and brittle. In adults, excess fluoride can cause brittle bones, weakness, and increase risk of cancer. On the other hand, research has concluded that fluoride in drinking water does decrease cavities by at least 25%. If you’re concerned about fluoride in your drinking water, either filter it out or use non-fluoridated bottled water. Since the evidence for or against fluoride is still controversial, you make the decision. Fluoride treatments by the dentist for your child every six months during the developing years are very beneficial. However, fluoride tablets given to infants are not necessary. Good nutrition and starting your child with proper oral hygiene habits are more important and worthwhile.
Crowns (caps), I was told by some, actually cause root canals. This is definitely a myth. Crowns do not cause root canals. If a crown is in place and years later a root canal is needed on the tooth, it may due to many reasons. A new cavity may have formed under the crown, which is not the fault of the crown, unless it was not fabricated properly, leaving an opening around the edge (open margin) allowing saliva and bacteria to seep through. If the original crown was placed due to the presence of a deep cavity and the dentist felt a root canal was not necessary at that time (that is a conservative approach which I like), but may be necessary later, and sometime later it becomes necessary, that does not mean the crown caused the root canal. I am not a proponent of root canals, however, as long as a cavity has reached the nerve, and there is severe pain (specially to hot), then a root canal is necessary. If there is also a large infection present, I recommend pulling the tooth instead of treating with a root canal. I’ve also heard complaints that crowns stop the flow of fluids out of the tooth and that’s why a filling is better. This myth insists that the fluids will go back into the body causing toxins, because they cannot escape through the dentin and enamel of the tooth (various layers of the tooth). If a very large filling is placed on a tooth, then that filling also is stopping the flow of any fluids from calling out of the surface. Also, a large filling cannot stand the stress placed on a tooth as well as a crown. The likelihood of the need for a root canal on this tooth in the future is increased.
Should I be afraid of my fillings, are the mercury fillings slowly poisoning me? The mercury fillings have been around for more than 150 years. They were used because they were inexpensive, durable and easy to work with. The controversy about them has been with us from the beginning. Mercury is extremely toxic. However, there are only a small percentage of people who have a known allergy to the form that is placed in the mouth. The mercury filling (amalgam) is actually a mixture of different materials such as silver, zinc, nickel, tin and other metals with approximately 50%-70% mercury. It is mixed with the other materials and when placed in a tooth it becomes hard. Studies have shown mercury vapor is given off slowly during chewing or tooth brushing.