Depending on which method the dentist uses and whether there is a dental technician at the clinic or nearby, a crown treatment will require one or two visits to the dentist.
The First Visit at the Clinic
The dentist starts off by sedate the tooth and the gum surrounding the tooth. Then the dentist will grind the tooth into a shape making room for the artificial crown. At the same time, damaged tooth material will be removed.
Grinding of the Tooth
When the tooth is grinded, the dentist will take an impression of the tooth and the surrounding teeth. Some dentists take an impression of both rows of teeth. The impression will be sent to a dental technician, who will make a model of the teeth. Based on the model, the technician makes a crown fitting the damaged tooth and the adjoining teeth.
Choice of Colour
If the surface of the crown is made of porcelain, the dentist will have to find a colour which fit in with the other teeth. Normally, the dentist has a series of small porcelain bits in different colours. By comparing the bits to the patient’s existing teeth, the dentist can chose the most suitable colour.
Finally, the dentist will attach a temporary crown to the tooth. Typically, a temporary crown is made of plastic and is attached to the tooth using temporary cement. The dentist may call the temporary crown a provisional crown. This step of the procedure will only be relevant if the dental technician is located far away from the clinic.
The Second Visit at the Clinic
When the temporary crown is removed, the dentist will place the crown on the tooth to see if it fits. The dentist will make sure that the colour and the shape of the crown suit the rest of the teeth. Maybe the crown needs small adjustments and sometimes it may be necessary also to grind the adjoining teeth.
Dental crowns are made in a variety of materials and colours. Which material is the better depends on which tooth the crown will cover. Moreover, different dentists prefer different material. One dentist will accentuate one material over another, and another dentist will say the opposite.
Crowns made for the teeth we use for chewing are often made in two layers; a core in metal (e.g. titan, gold or chrome/cobalt alloy) with a cover of ceramic porcelain. The combination of metal and ceramic components results in a strong tooth that still looks like a natural tooth. Crowns made for front teeth are often made of pure porcelain, as this material resembles the natural enamel the most. After all, the front teeth are the most visible teeth when we smile.
Some crowns are made of metal alloys, e.g. gold, silver, platinum or chrome/nickel alloys. They are very strong crowns and most often used for the teeth in the back of the mouth, where the pressure from chewing is high. However, the colour difference is unappealing for some people.
During the last few years, considerably stronger materials for crowns have been developed. Zirconium is almost as strong as the metal alloys, but the risk of allergies is less and zirconium crowns look very natural. These types of porcelain crowns are sold under different brand names such as: Procera AllCeram, Denzir, Empress and Vita-InCeram.