The dental laboratory that fabricates your dental crown requires accurate models of both your maxillary and mandibular arches, in order to create a perfect crown for your tooth. If you have chosen a full ceramic or porcelain fused to meal crown (PFM), your dentist will also require the exact shade of your tooth before he begins the preparation of the tooth.
The dental assistant will take alginate impressions of both your upper and lower dental arches. These impressions will be poured in stone to create a stone model of your teeth. The models will be sent to the dental laboratory for use when making your crown.
A small impression of the teeth in the same quadrant of the tooth that requires the crown and the opposing arch is also taken before the tooth is prepared. This impression is used to fabricate a temporary crown for you to wear until your permanent crown arrives back from the dental laboratory.
After the impressions have been finished, the dentist will then use a shade guide to record the exact color of your tooth. If your crown involves one of your front teeth, your dentist may ask you to visit the dental laboratory for the lab technician to take a custom shade of the surrounding teeth. If you have opted for a gold crown, there is no need to determine the shade of the tooth.