Crowns and Bridges: Procedural Overview
Tooth Preparation, Impression, and Provisional Restoration Appointment Expectations
Crown and bridge tooth preparation involves multiple appointments. The first appointment will include preparing the tooth (teeth), taking impressions, and making a provisional (temporary) restoration. This appointment will usually take the longest and be the most involved. In your case, you can expect to have an appointment that will be approximately hour(s). The more teeth that we prepare for crowns, the longer the appointment will last.
Tooth Preparation
The preparation of the teeth consists of shaping and removing tooth structure. This tooth reduction allows the ideal thickness of metal, porcelain, or metal and porcelain. The amount of tooth reduction necessary depends on the material we have selected; different types of crowns require different designs. We will make sure that you are comfortable throughout the entire procedure by numbing the area as needed.
Sometimes, because of the position of the soft tissue (gums), it may be necessary to trim or shape the soft tissue around the teeth. If we find that, due to unforeseen circumstances, the tissue removal will be complicated, you may be referred to a periodontist (gum specialist) for this procedure. If the tissue does not need to be reshaped, we most often use a “retraction cord” that is fitted and placed around the tooth. This cord temporarily repositions the gum tissue away from the prepared portion of the tooth and makes it possible to get a better impression.
Taking Impressions
Once the teeth have been adequately prepared, the final impressions are made. During this impression procedure, the prepared portions of the tooth must be clearly visible. The cleaner the prepared teeth are, the better the impression will be. To ensure accuracy we often take a second impression. This is a difficult and exacting task and some of the aspects of getting an acceptable impression are not in our control.
The impression material is mixed and placed into a special tray that conforms to the size of your mouth. Impression material is fairly soft when mixed, similar to cold molasses. Once placed in your mouth, the impression material will set in just a few minutes. Depending on the type of impression technique used, a separate model of the opposing teeth may also be made.
An impression of your bite (bite registration) will be used to be sure your final crown(s) will fit together with the opposite jaw, just as they did before.
Temporary or Provisional Restorations
After the impression is taken, the provisional (temporary) restoration(s) will be constructed. The temporary plastic/resin crown(s) replaces the prepared tooth structure and protects the tooth while the final crown is being fabricated. Provisional restorations are held in place with a temporary cement and will usually remain in your mouth for a minimum of 2 weeks¾longer if the required treatment is complex.
Your New “Look”
At the initial appointment we will make a determination of the shade of porcelain (or resin) to be used in order to obtain the best esthetic results. You will, of course, participate in this process. Many times we will take photographs of your teeth to better match the shade. The impression, bite registration, and shade information are sent to a laboratory; and the crown(s) or bridge(s) is constructed according to our explicit work order. The returned restoration will be ready for cementation (if simple) or for a casting try-in (if more complicated).
Following the First Appointment
How will you feel after the appointment is completed? Most patients note their gingival (gum) tissue is sore for a day or two. The less modification or manipulation of the gingival tissues, the less sore you will be. Some patients notice tooth sensitivity, especially to cold, but that it goes away pretty quickly. Analgesics (pain relief medication) are not usually necessary. If we expect you to be more than normally uncomfortable, we will inform you at the end of the appointment.
If you have any questions about tooth preparation, impression, and provisional restoration for crowns or bridges, please feel free to ask us.