Dental Fillings Discomfort
San Leandro’s Dr. Russo would like you to know what kinds of things will cause discomfort in your dental fillings. If you experience pain in or around your filling you should consult with him immediately to determine if there’s been any damage.
In modern dentistry, the material most commonly used to fill decaying teeth is known as dental amalgam, or a substance made by combining mercury with another metal. The amalgam consists of three solid phases having stoichiometries approximately corresponding to Ag2Hg3, Ag3Sn, and Sn8Hg. Anyone who bites a piece of aluminium foil in such a way that the foil presses against a dental filling will probably experience a momentary pain. In effect, an electrochemicalcell has been created, with aluminium (E0 = -1.66 V) as the anode and the saliva and filling as the electrolyte. Contact between the aluminium and the filling short circuits the cell, causing a weak current to flow between the electrodes. This thus stimulates the sensitive nerve within the tooth, causing an unpleasant sensation.
In addition, discomfort results when a less electro-positive metal touches a dental filling. For example, if a filling makes contact with a gold inlay in a nearby tooth, corrosion of the filling will occur. Here, the dental filling acts as the anode and the gold inlay acts as the cathode. As the Sn8Hg phase is the most likely to corrode, the release of the Sn (II) ions in the mouth produces the unpleasant metallic taste that we often feel. Prolonged corrosion will eventually result in another visit to the dentist for another replacement.
Sometimes a cavity can be very deep and close to the nerve. When this happens, the dentist will put a medicated temporary filling in the tooth for a while before putting in the permanent filling. This significantly reduces the chances of sensitivity especially to hot and cold.
Be careful with your fillings and please do not try to create a short circuit in your mouth. Ask Dr. Russo when you are getting you fillings done if they will interact with other fillings you may have. Call our office in San Leandro to discuss any discomfort in your fillings as soon as you experience pain.