Repair of Old Filling
Mrs. Tang comes to our office to get a crown for a tooth with root canal (R in Fig.1). Let us call it Tooth A. This tooth has lost majority of temporary filling, leaving a large cavity (C). There is a bad old filling (F) in the neighboring tooth (named Tooth B). This filling has an extra portion with rough surfaces (arrowhead in Fig.1; * in Fig.2). It can cause food entrapment between the teeth A and B, leading to new cavities later on. The filling in Tooth B should be fixed or totally replaced.
After removing the remaining filling from Tooth A, it is quite easy to remove the extra portion of the filling from Tooth B (black arrowhead in Fig.3). The old filling has a new smooth look! At the same appointment, a space (between red arrowheads) is created to insert a post in Tooth A (P in Fig.4). Finally, a crown (C in Fig.4) is placed to restore the tooth with a large cavity before.
The photo in Fig.4 is taken three years after crown placement. Mrs. Tang is happy about the crown and filling. There is no sign of new cavity in either Tooth A or Tooth B. The previously old filling still looks brand new. The main advantage of repair instead of total replacement is conservation of tooth structure. When an old filling is totally removed, some of tooth structure is inadvertently removed, creating tooth sensitivity after new filling is done.
Xin Wei, DDS, PhD, MS 1st edition 06/16/2011, last revision 06/17/2011