In this post I would like to describe a core buildup procedure which is often performed in addition to the crown restoration.
Core buildup is a restorative procedure where a missing portion of the tooth is restored with a dental filling material in order to support a crown restoration.
What are the Indications for Core Buildup?
When your tooth is badly broken or missing a large volume as a result of a disease process, an artificial dental crown may be indicated to restore function and appearance of the tooth. However the remaining portion of the tooth can be so small that it is not adequate enough to support a dental crown.
A certain amount of supporting tooth structure has to be present to support a dental crown so it can perform successfully over the long term. I will not go in great detail into the engineering aspects but rather say that the remaining tooth has to have a certain amount of height, surface area and taper to successfully hold the dental crown.
When there is a large amount of missing tooth we usually rebuild it with a filling material which is called Core Buildup. The purpose of the core buildup is to replace missing tooth structure, create optimal geometry for the crown restoration and protect integrity of the tooth.
How is Core Buildup Made?
Most commonly core buildup is made directly in the mouth from tooth colored polymer materials called dental composites. The surface of the tooth is usually prepared in order to maximize adherence of the filling to the tooth with the help of phosphoric acid etching and specially formulated dental adhesives.
If cavity process extends close to the nerve tissues located inside the root canal space of the tooth, dentist may also place a special calcium preparation to protect the nerve of the tooth.
When the volume of the missing tooth structure is very large and there is not much of the tooth material to support the filling dentist may also place threaded pins into the tooth which help retain composite filling. Also for teeth which had root canal treatment, a dentist may place a titanium or carbon fiber post into the canal space. Root posts help with the retention of the composite filling material.
Is Dental Crown Always Made on the Same Appointment as a Core Buildup?
Typically crown procedure which includes tooth preparation, impression and in some cases provisional placement is carried out immediately after placement of core buildup.
However in some instanced a dentist may decide to place a core build up and proceed with crown fabrication at a later time. In such situations core build up is shaped just like the natural tooth it replaces.
Most commonly this is done when there is a need to wait and see how the tooth respond over time. For example if there is a possibility of a root canal infection on a badly broken tooth, your dentist may place a core build up and evaluate the tooth over time.
In some instances when patient requires other types of treatment such as orthodontics or surgery the crown fabrication may be delayed as well. Also if patient is concerned about the cost, crown restoration can be completed at a later time and core buildup performs like a dental filling.
Case Example of Core Buildup and Dental Crown
A patient presented to our office with a loose gold dental restoration on the top molar.
Evaluation of this tooth revealed a cavity with decayed tooth tissues which has developed under old restoration. When we encounter this type of clinical situation we have to remove a diseased portion of the tooth in order to eliminate harmful bacteria and stop the progress of the cavity. Due to this fact, old restoration is not possible to use again since it will not fit well on the modified portion of the tooth. We have discuss our findings and treatment options and patient decided to have new crown made on this tooth. The tooth was anesthetized and working area was isolated with a dental dam. As a first step we removed all diseased tooth structure.
In the next step we made preparations for the buildup filling. The surface of the tooth was cleaned with antibacterial liquid. In additional we placed several small titanium pins to act as an armature for the support of the buildup filling. We also placed a special metal band which encircled the tooth so the build filling was contained inside the tooth and its excess did not come out of the tooth. Dental adhesive was applied and cured on the surface of the tooth. We than placed core buildup filling. As you can see in the photo below we restored the missing tooth structure to it original volume.
In the next step, tooth was prepared for crown restoration. After tooth preparation an impression was made and it was send to the dental laboratory for the fabrication of the dental crown. Plastic temporary crown was made and secured on the tooth while dental laboratory was making permanent crown.
In the last step permanent ceramic crown was secured with the help of the dental adhesive to the prepared tooth. The structural integrity, function and appearance of the tooth was restored with core buildup filling and dental crown.
Thank you for reading,
Dr. Alexander Shor
Drs. Alexander and Kavita Shor are certified specialists in Prosthodontics. Please contact us with questions or schedule an appointment for your dental needs!