Question
I have seven amalgam fillings, five defective and two intact. My dentist now suggests replacing all seven fillings. Does this make sense? Could the defective fillings be patched with other material? P.W. in V.
Short answer
If the fillings are still in good condition, it is generally not necessary to replace them. However, there may be aesthetic reasons for replacing gray fillings with white ones, or financial reasons. If all fillings could be replaced in just one visit to the dentist and with just one "injection", this would be more cost-effective overall than replacing the fillings individually at different times, says Dr. med. dent. Jürg Eppenberger, Lucerne, specialist dentist for reconstructive dentistry, member of the Swiss Dental Association, licensed dentist Hirslanden-Klinik St. Anna, Lucerne.
If a tooth needs to be removed, a decision must be made as to whether it needs to be replaced at all in order to ensure normal function, appealing aesthetics and perfect pronunciation. A missing first molar is usually replaced at your age if an opposing tooth is available.
Amalgam fillings are mechanically anchored in the tooth. This means that the dentist has to grind undercuts in the tooth so that the finished filling does not fall out again. For this reason, the individual parts may remain in the tooth even if an amalgam filling breaks. However, the fracture gap is an ideal entry point for bacteria, which can penetrate unhindered into the interior of the tooth and cause deep caries within a very short time (a few months). Such a situation must therefore be remedied as soon as possible.
In principle, a defective filling can also be repaired, provided that the part of the filling remaining in the tooth is still of sufficiently good quality. However, the problem of the fracture gap remains: A new, supplementary filling cannot be bonded tightly to an existing old one. This means that there is always a small gap between the two parts of the filling, which can provide an entry point for bacteria.
Provisional solution
A patch treatment is therefore generally a temporary solution. In the case of larger defects, replacing the filling is always gentler on the teeth, less risky and more cost-effective over a longer period of time.
In contrast to amalgam, modern white fillings are bonded into the tooth. A correctly made one-piece white filling has no entry points for bacteria between the tooth and the filling.
Discretionary question
Whether you should replace all fillings is a question of judgment that you must answer personally. If the two fillings are still in good condition, it is generally not necessary to replace them. However, there may be aesthetic reasons for replacing gray fillings with white ones, or financial reasons.
If all fillings could be replaced in just one visit to the dentist and with just one "injection", this would be more cost-effective overall than replacing the fillings individually at different times.
Author: Dr. med. dent. Jürg Eppenberger
Published in: Neue Luzerner Zeitung on April 23, 2007