When a restoration or filling is adapted to a prepared cavity to remove bacteria and decayed tooth, it is intended to repair that area of tooth for a long time. Restorations or fillings can fail due to recurring decay (a dental cavity that develops at the margin of a filling), coming debonded from the tooth (in the case of a composite where the restoration/tooth interface separate) or can fracture. Further, over a long period of time, a tooth can weaken at the margin of a restoration, especially if the tooth is undermined and the surrounding tooth can fracture.
Considering the above, there is the possibility that more tooth structure than the initial preparation is affected. If it is affected to the extent that a restoration will not provide a predictable functional tooth replacement, a crown might be necessary.
A crown essentially replaces the outer layer of a tooth with an artificial material like gold, base metals or porcelain. Zirconia crowns, for instance, have proven today to be both strong and esthetic. However, gold still is an excellent option for posterior teeth for those less concerned about esthetics. There are other options for crown materials as well. In the end, the tooth’s primary function in your mouth and relationship to your smile will determine the material Dr. Spear recommends for the crown.
Having a tooth restored by a crown often requires two separate appointments. At the first appointment, Dr. Spear will examine the tooth and likely take a radiograph to assess the extent of the issue. If the pulp of the tooth has been compromised he might need to perform root canal therapy prior to crowning the tooth.
Dr. Spear will then form an abutment on which to seat the crown, by prepping the outer part of the tooth to specifications that will allow ideal morphology and proper thickness to be created in the crown. Once this is done, Dr. Spear will make an impression of the area, capturing the margins of the preparation, which is sent to a quality dental lab where your permanent crown is uniquely made. A temporary crown is then made in the office and temporarily cemented over the abutment (the prepared remainder of the tooth) to protect it and provide chewing surfaces so that opposing and adjacent teeth do not shift and obliterate the space created by the preparation. Diet will need to be void of really crunchy or sticky things during this period as the temporary crown will not hold up to these things like the permanent crown will.
When the permanent crown is ready, Dr. Spear will call you in for a brief second appointment. This often takes 2-4 weeks, depending on the lab and particular situation. The temporary crown then is removed and your new permanent crown will be cemented or bonded in place over the abutment. If the temporary crown comes off while waiting for your permanent crown, it is very important to have it placed back on to avoid further issues, including shifting referenced above.
We hope this sheds some light on the process of crown necessity and fabrication. Please feel free to call Dr. Spear at 817.920.1488 to schedule an appointment to verify if any of your teeth might require this helpful service of getting crowned and becoming royalty! ?